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Search Results (2,040)

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16 pages, 830 KiB  
Article
Volatile Distribution in Flowers of Lathyrus odoratus L. by HS-SPME-GC Technique and Enantiomeric Separation Data
by James Calva, Mayerly Parra and Ángel Benítez
Plants 2024, 13(23), 3272; https://doi.org/10.3390/plants13233272 - 21 Nov 2024
Abstract
Lathyrus odoratus L., commonly known as sweet pea, is a plant with a distinctive aroma that can develop in various habitats. An analysis of the aromatic profile of the species was conducted using the HS-SPME (solid-phase microextraction headspace) technique. This study aimed to [...] Read more.
Lathyrus odoratus L., commonly known as sweet pea, is a plant with a distinctive aroma that can develop in various habitats. An analysis of the aromatic profile of the species was conducted using the HS-SPME (solid-phase microextraction headspace) technique. This study aimed to explore the composition of and variation in the floral scent emissions of L. odorathus. The floral scents from fresh flowers were collected over different months and analyzed using gas chromatography coupled with mass spectrometry on apolar and polar stationary phase columns. In the apolar column, the majority compounds included linalool (19.27–5.79%), α-trans-bergamotene (29.4–14.21%), and phenyl ethyl alcohol (30.01–1.56%), while on the polar column, the predominant compounds included myrcene (13.25%), (E,E)-α-farnesene (26.33–8.16%), α-trans-bergamotene (42.09–24.82%), and others. This investigation was complemented by enantioselective analysis using a chiral phase based in cyclodextrins, which revealed the presence of (1R)-(+)-α-pinene, (S)-(−)-limonene, (R)-(+)-germacrene D, and (R)-(E)-nerolidol as enantiomerically pure components and linalool as a racemic mixture. Notably, the principal component analysis (PCA) and heatmap revealed variations among the chemical compounds collected at different harvest times. This demonstrates that temporal factors indeed impact chemical compound production. Furthermore, research on the aromatic properties of flowers provides a theoretical basis for studying and improving the components of their scent. Full article
19 pages, 2737 KiB  
Article
Formulation and Characterization of β-Cyclodextrins–Nitazoxanide Inclusion Complexes: Enhanced Solubility, In Vitro Drug Release, and Antiviral Activity in Vero Cells
by Kuppu Sakthi Velu, Sonamuthu Jegatheeswaran, Muhammad Saeed Akhtar, Mohammad Rizwan Khan, Sonaimuthu Mohandoss and Naushad Ahmad
Pharmaceutics 2024, 16(12), 1494; https://doi.org/10.3390/pharmaceutics16121494 - 21 Nov 2024
Abstract
Background/Objectives: Nitazoxanide (NTX) exhibits promising therapeutic potential; its effectiveness is constrained by its low oral bioavailability due to its poor water solubility and limited permeability. Methods: This study focused on developing a complex of NTX with β-cyclodextrins (β-CDs), specifically β-CD and hydroxypropyl-β-cyclodextrin (Hβ-CD), [...] Read more.
Background/Objectives: Nitazoxanide (NTX) exhibits promising therapeutic potential; its effectiveness is constrained by its low oral bioavailability due to its poor water solubility and limited permeability. Methods: This study focused on developing a complex of NTX with β-cyclodextrins (β-CDs), specifically β-CD and hydroxypropyl-β-cyclodextrin (Hβ-CD), to enhance the solubility and antiviral activity of NTX. Results: The formation of the β-CD:NTX in an aqueous solution was verified using UV–visible spectroscopy, confirming a 1:1 inclusion complex. Characterization of the solid β-CD:NTX complexes was confirmed via FTIR, X-ray diffraction (XRD), scanning electron microscopy (SEM), and DSC-TGA analyses. Molecular docking studies revealed that the NTX thiazole ring with the nitro group was positioned within the β-CDs cavity, while the benzene ring remained outside. Phase solubility tests showed that β-CD:NTX complexes were formed with high stability constants, demonstrating a linear increase in NTX solubility as the β-CD concentration increased. Dissolution tests revealed rapid and nearly complete NTX release within 90 min for β-CD:NTX and Hβ-CD:NTX complexes. The β-CD:NTX complexes were tested for their antiviral activity against Herpes simplex virus (HSV-1) cultures. Results showed that the Hβ-CD:NTX complex had significantly higher antiviral efficacy than β-CD:NTX and free NTX alone. Moreover, cytotoxicity and cellular uptake studies on Vero cells indicated that the Hβ-CD:NTX complex demonstrated lower cytotoxicity and had the highest IC50 value, followed by β-CD:NTX and free NTX. Conclusions: These findings suggest that Hβ-CD:NTX inclusion complexes may serve as effective carriers for delivering NTX in HSV-1 treatments using Vero cell models. Full article
(This article belongs to the Special Issue Cyclodextrin-Based Gene and Drug Delivery Applications)
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<p>UV–visible absorption spectra of nitazoxanide (NTX) in the presence of (<b>a</b>) β-cyclodextrin (β-CD) and (<b>b</b>) hydroxypropyl-β-cyclodextrin (Hβ-CD) at pH 7.4 in phosphate-buffered saline solutions. Benesi–Hildebrand plots of 1/[A-A<sub>0</sub>] vs. (<b>c</b>) 1/[β-CD] and (<b>d</b>) 1/[Hβ-CD]. β-CD and Hβ-CD concentrations ranged from 0 to 0.012 M for measurements 1 to 7 (Black line to Purple line).</p>
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<p>Fourier transform infrared spectroscopy (FTIR) spectra of β-cyclodextrin (β-CD), hydroxypropyl-β-cyclodextrin (Hβ-CD), nitazoxanide (NTX), and their β-CD:NTX and Hβ-CD:NTX inclusion complexes.</p>
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<p>X-ray diffraction (XRD) patterns of β-cyclodextrin (β-CD), hydroxypropyl-β-cyclodextrin (Hβ-CD), nitazoxanide (NTX), and their β-CD:NTX and Hβ-CD:NTX inclusion complexes.</p>
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<p>Scanning electron microscopy (SEM) analysis of β-cyclodextrin (β-CD), hydroxypropyl-β-cyclodextrin (Hβ-CD), nitazoxanide (NTX), and their β-CD:NTX and Hβ-CD:NTX inclusion complexes.</p>
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<p>(<b>a</b>) Thermogravimetric analysis (TGA) and (<b>b</b>) differential scanning calorimetry (DSC) analysis of β-cyclodextrin (β-CD), hydroxypropyl-β-cyclodextrin (Hβ-CD), nitazoxanide (NTX), and their β-CD:NTX and Hβ-CD:NTX inclusion complexes.</p>
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<p>Molecular docking of β-cyclodextrin (β-CD), hydroxypropyl-β-cyclodextrin (Hβ-CD), nitazoxanide (NTX), and their β-CD:NTX and Hβ-CD:NTX inclusion complexes. (NTX; Tan, red, blue, yellow, and white colors corresponding to the carbon, oxygen, nitrogen, sulfur, and hydrogen atoms).</p>
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<p>Phase solubility study of nitazoxanide (NTX) in the presence of (<b>a</b>) β-cyclodextrin (β-CD) and (<b>b</b>) hydroxypropyl-β-cyclodextrin (Hβ-CD).</p>
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<p>In vitro drug release studies of pure NTX and its β-CD:NTX and Hβ-CD:NTX inclusion complexes.</p>
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<p>Antiviral activity test at (<b>a</b>) 24 h and (<b>b</b>) 48 h. Controlled exposure antiviral assay for (<b>c</b>) 6 h and (<b>d</b>) 12 h (data are the mean ± SD of experiments * <span class="html-italic">p</span> &lt; 0.05, ** <span class="html-italic">p</span> &lt; 0.01, *** <span class="html-italic">p</span> &lt; 0.001, **** <span class="html-italic">p</span> &lt; 0.0001), below the limit of detection (using the TCID<sub>50</sub> method).</p>
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<p>(<b>a</b>) Effect of different nitazoxanide (NTX) drug formulations on the viability of Vero cells as a function of free NTX and its β-cyclodextrin (β-CD):NTX and hydroxypropyl-β-cyclodextrin (Hβ-CD):NTX inclusion complexes at 48 h and (<b>b</b>) fluorescence microscopy images using phase-contrast, 4′,6-diamidino-2-phenylindole (DAPI), and fluorescein isothiocyanate (FITC) staining of control, NTX, and their β-CD:NTX and Hβ-CD:NTX inclusion complexes at 150 μg/mL for 48 h in Vero cells. Scale bar = 50 μm.</p>
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17 pages, 2647 KiB  
Article
Biopharmaceutical Characterization and Stability of Nabumetone–Cyclodextrins Complexes Prepared by Grinding
by David Klarić, Željka Soldin, Anna Vincze, Rita Szolláth, György Tibor Balogh, Mario Jug and Nives Galić
Pharmaceutics 2024, 16(12), 1493; https://doi.org/10.3390/pharmaceutics16121493 - 21 Nov 2024
Abstract
Background: Nabumetone (NAB) is a poorly soluble nonsteroidal anti-inflammatory prodrug (BCS class II drug) whose solubility is significantly improved by complexation with cyclodextrins (CDs). Methods: The solid complexes, in a 1:1 molar ratio, were prepared by mechanochemical activation by grinding, using β-cyclodextrin [...] Read more.
Background: Nabumetone (NAB) is a poorly soluble nonsteroidal anti-inflammatory prodrug (BCS class II drug) whose solubility is significantly improved by complexation with cyclodextrins (CDs). Methods: The solid complexes, in a 1:1 molar ratio, were prepared by mechanochemical activation by grinding, using β-cyclodextrin (β-CD) and its derivatives, hydroxypropyl- and sulfobutylether-β-cyclodextrin (HP-β-CD and SBE-β-CD). The complexation was confirmed by differential scanning calorimetry (DSC), powder X-ray diffraction (PXRD), and attenuated total reflectance Fourier-transformed infrared spectroscopy (ATR–FTIR). Obtained products were further characterized regarding their solubility, in vitro dissolution, permeability and chemical stability. Results: Co-grinding with HP-β-CD and SBE-β-CD yielded products that showed in vitro dissolution profiles in hydrochloric acid medium (pH 1.2) that were substantially different from that of pure NAB, yielding dissolution efficiency enhancements of 34.86 ± 1.64 and 58.30 ± 0.28 times, respectively, for the optimized products. Their in vitro dissolution and gastrointestinal permeability were also studied in a low-volume environment at pH 6.8, corresponding to the intestinal environment. Both β-CD derivatives increased NAB dissolution rate and NAB mass transport across the biomimetic membrane. The effect of β-CD derivatives on NAB chemical stability was studied under the stress conditions by the developed and validated UHPLC–DAD–HRMS method. In acidic conditions, pure and complexed NAB was prone to hydrolytic degradation, yielding one degradation product—pharmacologically inactive NAB metabolite. However, under the oxidative conditions at elevated temperatures, 10 NAB degradation products were identified from co-ground samples. All systems were stable during photo- and long-term stability studies. Conclusions: NAB complexes with HP-β-CD and SBE-β-CD are promising candidates for pharmaceutical product development. Full article
(This article belongs to the Special Issue Supramolecular Systems for Gene and Drug Delivery, 2nd Edition)
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<p>Structural formulas of nabumetone (NAB), β-cyclodextrin (β-CD), and their derivatives.</p>
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<p>DSC thermograms (<b>left</b>) and XRPD diffractograms (<b>right</b>) of starting compounds (NAB and β-CD), ground and co-evaporated drug (NAB GR and NAB COE), physical mixture (NAB/β-CD PM), and complexes obtained by co-grinding (NAB/β-CD GR) and co-evaporation (NAB/β-CD COE). The results for the systems prepared with HP-β-CD and SBE-β-CD are presented in <a href="#app1-pharmaceutics-16-01493" class="html-app">Supporting Information (Figures S1 and S2, respectively)</a>.</p>
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<p>Saturation solubility of NAB and co-ground CD complexes in a hydrochloric acid medium pH 1.2 and a hydrochloric acid medium pH 1.2 with 2% (<span class="html-italic">w</span>/<span class="html-italic">V</span>) sodium lauryl sulfate (insert) at 37 °C. One asterisk (*) denotes a statistically significant difference (<span class="html-italic">p</span> &lt; 0.05) compared to pure NAB, two asterisks (**) denote a statistically significant difference (<span class="html-italic">p</span> &lt; 0.05) compared to β-CD complex, and three asterisks (***) denote a statistically significant difference (<span class="html-italic">p</span> &lt; 0.05) compared to HP-β-CD complex. Sample codes: NAB (A), NAB GR (B), NAB/β-CD GR (C), NAB/HP-β-CD GR 20 Hz/120 min (D), NAB/HP-β-CD GR 30 Hz/90 min (E), NAB/SBE-β-CD GR 20 Hz/120 min (F), and NAB/SBE-β-CD GR 30 Hz/120 min (G).</p>
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<p>In vitro dissolution profiles of NAB and its co-ground products with CDs in hydrochloric acid medium at 37 °C.</p>
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<p>The 4-hour dissolution profiles of NAB (A), NAB/HP-β-CD 30 Hz/90 min (E), and NAB/SBE-β-CD 30 Hz/120 min (G) in PBS, pH 6.8, at 37 °C (<b>left</b>) and the thermodynamic solubility of the samples at 24 h (37 °C, PBS pH 6.8) (<b>right</b>). Significant differences are indicated with an asterisk: * <span class="html-italic">p</span> &lt; 0.05 (n = 3, one-way ANOVA, Tukey’s multiple comparisons test).</p>
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<p>In vitro gastrointestinal flux (<b>left</b>) and permeability (<b>right</b>) of NAB (A), NAB/HP-β-CD 30 Hz/90 min (E), and NAB/SBE-β-CD 30 Hz/120 min (G). Significant differences are indicated with an asterisk: * <span class="html-italic">p</span> &lt; 0.05 (n = 3, one-way ANOVA, Tukey’s multiple comparisons test).</p>
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<p>HRMS spectrum of degradation product DP 1 (<span class="html-italic">t</span><sub>R</sub> = 10.9 min) formed during the acidic hydrolytic degradation.</p>
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<p>Proposed degradation products of NAB in hydrolytic (HCl) and oxidative conditions (H<sub>2</sub>O<sub>2</sub>). Experimental conditions: 2M HCl; 3% H<sub>2</sub>O<sub>2</sub> at 80 °C.</p>
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10 pages, 2504 KiB  
Article
Improved Kaempferol Solubility via Heptakis-O-(2-hydroxypropyl)-β-cyclodextrin Complexation: A Combined Spectroscopic and Theoretical Study
by Dongxu Han, Zhongbao Han, Liyan Liu, Shigang Xin and Zhan Yu
Int. J. Mol. Sci. 2024, 25(23), 12492; https://doi.org/10.3390/ijms252312492 - 21 Nov 2024
Viewed by 142
Abstract
Four cyclodextrins (CDs) including heptakis-O-(2-hydroxypropyl)-β-cyclodextrin (HP-β-CD), heptakis-O-(2,6-di-O-methyl)-β-cyclodextrin (DM-β-CD), β-cyclodextrin (β-CD), and γ-cyclodextrin (γ-CD) were evaluated for their ability to enhance the aqueous solubility of kaempferol (Kae). Phase solubility studies indicated that these four CDs can form 1:1 type complexes with Kae and that [...] Read more.
Four cyclodextrins (CDs) including heptakis-O-(2-hydroxypropyl)-β-cyclodextrin (HP-β-CD), heptakis-O-(2,6-di-O-methyl)-β-cyclodextrin (DM-β-CD), β-cyclodextrin (β-CD), and γ-cyclodextrin (γ-CD) were evaluated for their ability to enhance the aqueous solubility of kaempferol (Kae). Phase solubility studies indicated that these four CDs can form 1:1 type complexes with Kae and that HP-β-CD demonstrated the most significant solubilizing effect on Kae. Among the CDs tested, HP-β-CD demonstrated the most significant solubilizing effect on Kae. With an HP-β-CD concentration of 5.00 × 10−3 mol·L−1, the concentration of Kae reached 4.56 × 10−5 mol·L−1, which is 12.7 times greater than its solubility in water. Characterization of the HP-β-CD/Kae complex was performed using empirical methods. Molecular docking indicated that the A and C rings of Kae fit into the hydrophobic cavity of HP-β-CD, while the B ring remained at the rim. Six hydrogen bonds were found between HP-β-CD and the -OH groups of Kae. The negative complexation energy (ΔE) suggests the complex formation was exergonic. A 30-ns molecular dynamics simulation revealed no significant structural changes, with average root-mean-square deviation RMSD values of 2.230 Å for HP-β-CD and 0.786 Å for Kae, indicating high stability of the complex. Full article
(This article belongs to the Collection Feature Papers in Bioactives and Nutraceuticals)
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<p>Chemical structures of CDs, including β-CD, γ-CD, DM-β-CD and HP-β-CD (<b>A</b>) as well as Kae (<b>B</b>).</p>
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<p>Phase solubility diagrams of Kae in aqueous solution with the presence of various CDs.</p>
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<p>FT-IR spectra of HP-β-CD/Kae inclusion complex (a), HP-β-CD/Kae physical mixture (b), HP-β-CD (c), and Kae (d).</p>
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<p>XRD patterns of HP-β-CD/Kae inclusion complex (a), HP-β-CD/Kae physical mixture (b), HP-β-CD (c), and Kae (d).</p>
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<p>TG (<b>A</b>) and DTG (<b>B</b>) curves of HP-β-CD/Kae inclusion complex (a), HP-β-CD/Kae physical mixture (b), HP-β-CD (c), and Kae (d).</p>
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<p>Snapshot of the lowest energy docking result for CD/Kae complexes, where CD is β-CD (<b>a</b>), γ-CD, (<b>b</b>) DM-β-CD (<b>c</b>), or HP-β-CD (<b>d</b>). The hydrogen bonds are represented by dashed lines with indicated distances (in Å).</p>
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<p>RMSD plots of all atoms for HP-β-CD/Kae complex.</p>
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16 pages, 2518 KiB  
Article
Methyl-Beta-Cyclodextrin Restores Aberrant Bone Morphogenetic Protein 2-Signaling in Bone Marrow Stromal Cells Obtained from Aged C57BL/6 Mice
by Daniel Halloran, Venu Pandit, Kelechi Chukwuocha and Anja Nohe
J. Dev. Biol. 2024, 12(4), 30; https://doi.org/10.3390/jdb12040030 - 18 Nov 2024
Viewed by 351
Abstract
During aging, disruptions in various signaling pathways become more common. Some older patients will exhibit irregular bone morphogenetic protein (BMP) signaling, which can lead to osteoporosis (OP)—a debilitating bone disease resulting from an imbalance between osteoblasts and osteoclasts. In 2002, the Food and [...] Read more.
During aging, disruptions in various signaling pathways become more common. Some older patients will exhibit irregular bone morphogenetic protein (BMP) signaling, which can lead to osteoporosis (OP)—a debilitating bone disease resulting from an imbalance between osteoblasts and osteoclasts. In 2002, the Food and Drug Administration (FDA) approved recombinant human BMP-2 (rhBMP-2) for use in spinal fusion surgeries as it is required for bone formation. However, complications with rhBMP-2 arose and primary osteoblasts from OP patients often fail to respond to BMP-2. Although patient samples are available for study, previous medical histories can impact results. Consequently, the C57BL/6 mouse line serves as a valuable model for studying OP and aging. We find that BMP receptor type Ia (BMPRIa) is upregulated in the bone marrow stromal cells (BMSCs) of 15-month-old mice, consistent with prior data. Furthermore, conjugating BMP-2 with Quantum Dots (QDot®s) allows effective binding to BMPRIa, creating a fluorescent tag for BMP-2. Furthermore, after treating BMSCs with methyl-β-cyclodextrin (MβCD), a disruptor of cellular endocytosis, BMP signaling is restored in 15-month-old mice, as shown by von Kossa assays. MβCD has the potential to restore BMPRIa function, and the BMP signaling pathway offers a promising avenue for future OP therapies. Full article
(This article belongs to the Special Issue The 10th Anniversary of JDB: Feature Papers)
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<p>Increased protein detection of BMPRIa in the BMSCs isolated from the 15-month-old mice compared to the control 6-month-old B6 mice. The BMSCs were isolated from the femurs of the 6- and 15-month-old B6 mice. The cells were grown, without additional stimulation, for 10–12 days. (<b>A</b>) Lysates were collected and probed for BMPRIa. Protein concentration was normalized and GAPDH was used as the loading control. The protein concentration was quantified via densitometry measurements and statistical significance is displayed by the “*”. The <span class="html-italic">p</span>-value was set to 0.05 and the significance was calculated with Student’s <span class="html-italic">t</span>-test. (<b>B</b>) BMPRIa was detected via immunofluorescent staining and images were acquired with confocal microscopy. Representative images are displayed and the scalebars are set to 10 µm.</p>
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<p>Representative high-resolution z-stack images showing BMPRIa localization in the orthogonal view from the US BMSCs isolated from the 6- and 15-month-old C57BL/6 mice. Immunofluorescence staining was performed using an anti-BMPRIa antibody. BMPRIa is shown in red, and nuclei are stained with Hoechst dye (blue). The images were captured at 63× magnification; scale bar = 10 μm. The orthogonal view provides slices through different regions of the cell, allowing for the precise visualization of BMPRIa localization. BMPRIa is observed to be localized to the plasma membrane in BMSCs from both age groups (6 and 15 months).</p>
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<p>Immunostaining of the BMSCs isolated from the 6-month-old female B6 mice. The cells were obtained from the 6-month-old mice and stimulated with BMP-2-QDot<sup>®</sup>s, MβCD, or left US. The cells were immunostained and observed with confocal microscopy. Representative images are displayed, and the scale bars are set to 10 μm. Z-10 images are obtained with a 63x objective and magnified 10× to observe the precise localization of BMPRIa or BMP-2 and the scale bars are set to 1 μm.</p>
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<p>Immunostaining of the BMSCs isolated from the 15-month-old female B6 mice. The cells were obtained from the 15-month-old mice and stimulated with BMP-2-QDot<sup>®</sup>s, MβCD, or left US. The cells were immunostained and observed with confocal microscopy. Representative images are displayed, and the scale bars are set to 10 μm. Z-10 images are obtained with a 63x objective and magnified 10× to observe the precise localization of BMPRIa or BMP-2 with the scale bars set to 1 μm.</p>
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<p>Quantification of immunostaining conducted on BMSCs. To further assess the increase or decrease in BMPRIa localization and BMP-2 binding, the images acquired from the confocal microscopy were semi-quantified. Fluorescence was calculated with at least 10 cells that were imaged and analyzed in ImageJ. The fluorescence from the cells was averaged for both BMPRIa and BMP-2-QDs. (<b>A</b>) The red fluorescence of BMPRIa was measured across all the conditions of both 6- and 15-month-old B6 mice. (<b>B</b>) The green fluorescence of BMPRIa was measured across all the conditions of both the 6- and 15-month-old B6 mice. The SEM bars are displayed above each bar. All the data were analyzed in ImageJ and statistical analyses were performed with the Tukey–Kramer HSD test. Statistical significance was set to <span class="html-italic">p</span> ≤ 0.05 and is displayed as lettering; here, the letters represent group one as the letter “a”, group two corresponds to the letter “b”, and so on. For example, if there is a letter “a” above a bar, that means this group is statistically different from group one.</p>
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<p>Von Kossa assay of the MβCD-treated BMSCs isolated from the 6- and 15-month-old mice. The BMSCs were obtained from the 6- and 15-month-old female B6 mice and treated with MβCD or left untreated. Afterward, the cells were stimulated with BMP-2 or left US. BMP-2 enhanced mineralization in the 6-month-old cells in both MβCD-treated and untreated cells, whereas in 15-month-old cells, only BMP-2 + MβCD led to mineralization. Random images were obtained from each condition and analyzed in ImageJ. Representative images are displayed underneath each bar. The error bars represent SEM and significance was determined using the Tukey–Kramer-HSD test. Statistical significance was set to <span class="html-italic">p</span> ≤ 0.05 and is displayed as lettering; here, the letters represent group one as the letter “a”, group two corresponds to the letter “b”, and so on. For example, if there is a letter “a” above a bar, that means this group is statistically different from group one.</p>
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17 pages, 5675 KiB  
Article
Antibacterial and Inhibitory Activity of Nora and Mepa Efflux Pumps of Estragole Complexed to β-Cyclodextrin (ES/β-CD) In Vitro Against Staphylococcus aureus Bacteria, Molecular Docking and MPO-Based Pharmacokinetics Prediction
by Roger Henrique Sousa da Costa, Renata Torres Pessoa, Eduardo dos Santos Silva, Isaac Moura Araujo, Sheila Alves Gonçalves, Janaína Esmeraldo Rocha, Francisco Nascimento Pereira Junior, Naiara Cipriano Oliveira, Victor Moreira de Oliveira, Matheus Nunes da Rocha, Emmanuel Silva Marinho, Natália Kelly Gomes de Carvalho, José Galberto Martins da Costa, Hélcio Silva dos Santos and Irwin Rose Alencar de Menezes
Pharmaceutics 2024, 16(11), 1469; https://doi.org/10.3390/pharmaceutics16111469 - 18 Nov 2024
Viewed by 370
Abstract
Background/Objectives: The work investigates the effect of the estragole complex encapsulated in beta-cyclodextrin (ES/β-CD) in modulating bacterial resistance, specifically in Staphylococcus aureus strains expressing NorA and MepA efflux pumps. Efflux pumps are mechanisms that bacteria use to resist antibiotics by expelling them from [...] Read more.
Background/Objectives: The work investigates the effect of the estragole complex encapsulated in beta-cyclodextrin (ES/β-CD) in modulating bacterial resistance, specifically in Staphylococcus aureus strains expressing NorA and MepA efflux pumps. Efflux pumps are mechanisms that bacteria use to resist antibiotics by expelling them from the cell. Methodology: Several compounds and antibiotics, such as ciprofloxacin and norfloxacin, were used to evaluate the antimicrobial activity and the ability of the ES/β-CD complex to reverse resistance. Methods: The study included scanning electron microscopy assays, minimum inhibitory concentration (MIC) determination, and efflux pump inhibition tests. Results: The ES/β-CD complex did not show significant direct antibacterial activity. However, it modulated the action of norfloxacin, decreasing the MIC when combined with this antibiotic in the 1199B (NorA) strain. These results suggest a potential for synergy but not a direct inhibition of efflux pumps. Conclusion: ES/β-CD can potentiate the efficacy of some antibiotics but does not directly act as an efflux pump inhibitor; it is more of an antibiotic potentiator than a direct solution to bacterial resistance. The molecular docking simulation data suggest its high affinity for forming the ES/β-CD complex. The pharmacokinetic predictions based on MPO suggest that the compound has moderate lipophilicity, highly effective cellular permeability, and low incidence of organic toxicity, pointing to a promising pharmacological principle with controlled daily oral dosing. Conclusions: These results indicate this complex’s possible and relevant association as an adjuvant in antibiotic therapy to reduce multidrug-resistant bacteria; however, new in vivo assays are necessary to confirm this effect. Full article
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<p>SEM images of pure β-cyclodextrin (β-CD) (<b>A</b>–<b>C</b>) and β-cyclodextrin associated with estragole (ES/β-CD) (<b>D</b>–<b>F</b>) are presented. To provide further details of the surface morphology before and after estragole association, higher-magnification images of the regions highlighted in red ((<b>A</b>,<b>B</b>) for β-CD, and (<b>C</b>,<b>D</b>) for ES/β-CD) are shown in (<b>C</b>,<b>F</b>), respectively.</p>
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<p>GC/FID profile of the estragole pattern (RT: 7.648 min).</p>
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<p>GC/FID profile of the β-cyclodextrin complex in estragole. Estragole (RT: 7.646 min).</p>
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<p>Evaluation of efflux pump inhibition of the products when associated with norfloxacin and ethidium bromide against <span class="html-italic">S. aureus</span> strain-overexpressing NorA efflux pumps. Each result is expressed as geometric mean ± geometric standard deviation (SD) of three simultaneous experiments. Statistical significance was determined by one-way ANOVA and Bonferroni’s post hoc test. The control contains only the vehicle solution of dimethyl sulfoxide (DMSO). (** <span class="html-italic">p</span> &lt; 0.01, **** <span class="html-italic">p</span> &lt; 0.0001 when compared to the negative control group).</p>
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<p>Evaluation of efflux pump inhibition of the products when associated with ciprofloxacin and ethidium bromide against <span class="html-italic">S. aureus</span> strain-overexpressing MepA efflux pumps. Each result is expressed as geometric mean ± geometric standard deviation (SD) of three simultaneous experiments. Statistical significance was determined by one-way ANOVA and Bonferroni’s post hoc test (ns—no significance; * <span class="html-italic">p</span> &lt; 0.05; ** <span class="html-italic">p</span> &lt; 0.01, **** <span class="html-italic">p</span> &lt; 0.0001 when compared to the negative control group).</p>
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<p>(<b>A</b>) Frontal view of β-CD in two units and (<b>B</b>) β-CD presented in the lateral plane.</p>
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<p>(<b>A</b>) Complex formed between β-CD and ES. (<b>B</b>) Surface of the complex formed in the frontal plane. (<b>C</b>) Surface of the complex with lateral view.</p>
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<p>(<b>A</b>) Global view of interactions formed from the ES-β-CD complex. (<b>B</b>) Specific moieties that formed interactions.</p>
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<p>(<b>A</b>) Molecular lipophilicity potential (MLP) surface map, where the color spectrum ranges from blue (low MLP) to red (high MLP). (<b>B</b>) Alignment between lipophilicity (logP) and polarity (TPSA) for estimating the MPO drug candidate profile and CNS toxicity.</p>
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<p>Prediction of pharmacokinetic properties and toxicity expressed in (<b>A</b>) a similarity test involving compounds present in the DrugBank<sup>®</sup> database, (<b>B</b>) prediction of lethal dose (LD50) for different routes of administration (oral, IP—intraperitoneal, IV—intravenous and SC—subcutaneous), (<b>C</b>) statistical limit of the similarity test of the predictions of (<b>D</b>) oral toxicity site and CYP450-dependent metabolism site.</p>
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16 pages, 8336 KiB  
Article
Functionalized Cyclodextrin/Carboxymethyl Cellulose Composite Hydrogel with Double Network Structure for Adsorption of Heavy Metal Ions in Wastewater
by Hong Zhang, Xiaodong Yang, Xin Zhang, Wenbin Liu, Meiqing Fan and Lei Wang
Molecules 2024, 29(22), 5414; https://doi.org/10.3390/molecules29225414 - 16 Nov 2024
Viewed by 361
Abstract
Heavy metal ions in industrial wastewater pose significant environmental and ecological threats. In this work, a hydrogel featuring a double network structure was synthesized via radical polymerization and cross-linking of β-cyclodextrin (CD) and carboxymethylcellulose (CMC) with acrylic acid (AA). The hydrogel’s functional groups [...] Read more.
Heavy metal ions in industrial wastewater pose significant environmental and ecological threats. In this work, a hydrogel featuring a double network structure was synthesized via radical polymerization and cross-linking of β-cyclodextrin (CD) and carboxymethylcellulose (CMC) with acrylic acid (AA). The hydrogel’s functional groups and microstructure were characterized using Fourier transform infrared spectroscopy (FTIR-ATR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and thermogravimetric analysis (TGA). Mechanical properties were evaluated through rheological and compression tests. The study examined the impact of initial metal ion concentration, adsorbent-ion contact time, and solution pH on adsorption capacity. The maximum adsorption capacities of the functionalized CD/CMC-PAA-MBA hydrogel for Cu2+, Pb2+, and Cd2+ ions were 158.12, 393.56, and 290.12 mg/g, respectively. Notably, the hydrogel exhibited the highest selectivity for Pb2+ in mixed solutions. The adsorption kinetics of the metal ions were modeled using the pseudo-second-order rate equation and the Langmuir adsorption isotherm. Full article
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<p>Synthesis process of composite hydrogel CD/CMC-PAA-MBA.</p>
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<p>(<b>a</b>) FTIR-ATR spectra of CD, CMC, and CD/CMC-PAA-MBA; (<b>b</b>) XRD curves of CD, CMC, and CD/CMC-PAA-MBA; (<b>c</b>) TGA curves of CD, CMC, and CD/CMC-PAA-MBA; (<b>d</b>) 10 cycles of compression curves of CD/CMC-PAA-MBA.</p>
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<p>(<b>a</b>) Storage modulus (G′) and loss modulus (G″) vs strain of the CD/CMC−PAA−MBA hydrogels and (<b>b</b>) storage modulus (G′) and loss modulus (G″) vs angular frequency of the CD/CMC-PAA−MBA hydrogels.</p>
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<p>SEM images of (<b>a</b>) CD/CMC-PAA-MBA, (<b>b</b>) SEM images of Cu<sup>2+</sup>-loaded CD/CMC−PAA−MBA, (<b>c</b>) SEM images of Pb<sup>2+</sup>−loaded CD/CMC−PAA−MBA, and (<b>d</b>) SEM images of Cd<sup>2+</sup>−loaded CD/CMC−PAA−MBA.</p>
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<p>Effect of (<b>a</b>) pH, (<b>b</b>) temperature, (<b>c</b>) contact time, and (<b>d</b>) initial metal ion concentration on the adsorption of Cu<sup>2+</sup>, Pb<sup>2+</sup>, and Cd<sup>2+</sup> ions by CD/CMC-PAA-MBA.</p>
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<p>(<b>a</b>) Langmuir, (<b>b</b>) Freundlich, and (<b>c</b>) Temkin adsorption isotherm model for Pb<sup>2+</sup>, Cd<sup>2+</sup>, and Cu<sup>2+</sup> adsorption.</p>
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<p>(<b>a</b>) Pseudo−first−order and (<b>b</b>) pseudo−second order kinetic adsorption model for Pb<sup>2+</sup>, Cd<sup>2+</sup>, and Cu<sup>2+</sup> adsorption.</p>
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<p>Experiments of CD/CMC−PAA−MBA regeneration performance.</p>
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<p>(<b>a</b>) Digital photo of the form of Cu<sup>2+</sup> adsorbed by hydrogel, (<b>b</b>) digital photo of the form of Pb<sup>2+</sup> adsorbed by hydrogel, and (<b>c</b>) digital photo of the form of Cd<sup>2+</sup> adsorbed by hydrogel.</p>
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<p>Adsorption of metal ions on CD/CMC−PAA−MBA composite hydrogels.</p>
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18 pages, 5753 KiB  
Article
Mycoplasma bovis Invades Non-Phagocytic Cells by Clathrin-Dependent Endocytic Pathways and Escapes from Phagocytic Vesicles
by Bin Li, Yabin Lu, Yaru Feng, Xiaolong Jiao, Qiuyu Zhang, Mengting Zhou, Yuyu Zhang, Jian Xu, Yuefeng Chu and Duoliang Ran
Pathogens 2024, 13(11), 1003; https://doi.org/10.3390/pathogens13111003 - 15 Nov 2024
Viewed by 344
Abstract
Mycoplasma bovis (M. bovis) is capable of causing pneumonia, arthritis, mastitis, and various other ailments in cattle of all age groups, posing a significant threat to the healthy progression of the worldwide cattle industry. The invasion of non-phagocytic host cells serves [...] Read more.
Mycoplasma bovis (M. bovis) is capable of causing pneumonia, arthritis, mastitis, and various other ailments in cattle of all age groups, posing a significant threat to the healthy progression of the worldwide cattle industry. The invasion of non-phagocytic host cells serves as a pivotal mechanism enabling M. bovis to evade the immune system and penetrate mucosal barriers, thereby promoting its spread. To investigate the differences in M. bovis invasion into four types of non-phagocytic cells (Madin–Darby bovine kidney (MDBK) cells, embryonic bovine lung (EBL) cells, bovine embryo tracheal (EBTr) cells and bovine turbinate (BT) cells) and further elucidate its invasion mechanism, this study first optimized the experimental methods for M. bovis invasion into cells. Utilizing laser scanning confocal microscopy, transmission electron microscopy, and high-content live-cell imaging systems, the invasion process of M. bovis into four types of non-phagocytic cells was observed. The invasion rates of three different strains of M. bovis (PG45, 07801, 08M) were quantified through the plate counting method. In order to clarify the specific pathway of M. bovis invasion into cells, chlorpromazine (CPZ), amiloride (AMI), and methyl-β-cyclodextrin (M-β-CD) were used to inhibit CLR-mediated clathrin-dependent endocytosis (CDE) pathway, macropinocytosis, and lipid raft pathway, respectively. Subsequently, the invasion rates of PG45 into these four types of cells were measured. Using siRNA technology, the expression of clathrin (CLR) in EBL cells was knocked down to further verify the role of CLR in the invasion process of M. bovis. The results showed that the optimal conditions for M. bovis to invade non-phagocytic cells were a multiplicity of infection (MOI) of 1000 and an optimal invasion time of 4 h. All three strains of M. bovis have the ability to invade the four types of non-phagocytic cells, yet their invasion abilities vary significantly. Observations from transmission electron microscopy further confirmed that at 120 min post-infection, PG45 had successfully invaded EBL cells and was present within endocytic vesicles. It is noteworthy that almost all PG45 successfully escaped from the endocytic vesicles after 240 min of infection had passed. Through chemical inhibition experiments and CLR protein knockdown experiments, it was found that when the CDE and lipid raft pathways were blocked or CLR protein expression was reduced, the invasion rates of PG45, 07801, and 08M in MDBK, EBL, EBTr, and BT cells were significantly decreased (p < 0.05). The above results indicate that M. bovis can invade all types of non-phagocytic cells through endocytic pathways involving CDE (clathrin-dependent endocytosis) or lipid raft-mediated endocytosis, and possesses the ability to escape from phagosomes. Full article
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<p>Optimal selection of MBC and MOC. Different concentrations of Tetracycline, tiamulin, gentamicin, and azithromycin were added to the culture medium containing PG45. Tetracycline (<b>A</b>) and gentamicin (<b>C</b>) with a working concentration of 200 µg/mL to 400 µg/mL, as well as azithromycin (<b>D</b>) and tiamulin (<b>B</b>) with a working concentration of 400 µg/mL to 1000 µg/mL, can all effectively kill PG45. Under the condition of acting for 3 h, both gentamicin (<b>E</b>) and tiamulin (<b>F</b>) with a working concentration of 400 µg/mL can completely kill PG45. Different MOIs of PG 45 were added to EBL cells, when it increased to 100 of MOI, the invasion rate of PG45 began to be statistically significant (<b>G</b>). PG45 was added to EBL cells at an MOI of 1000, and the invasion rate of PG45 was measured by observing different interaction times (<b>H</b>). The cell morphology of PG45-infected EBL cells with an MOI of 1000 for 240 min, the morphology of EBL was essentially normal (100×) (<b>I</b>). After 240 min of infection with PG45 at an MOI of 10,000, EBL cells exhibited wrinkling and cytopathic effects (100×) (<b>J</b>).* <span class="html-italic">p</span> &lt; 0.05; ** <span class="html-italic">p</span> &lt; 0.01; NS, no significant difference (<span class="html-italic">p</span> &gt; 0.05).</p>
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<p>Protocol and results of <span class="html-italic">M. bovis</span> intracellular survival test. (<b>A</b>) Intracellular viability assay protocol of <span class="html-italic">M. bovis</span>. (<b>B</b>) CFUs of extracellular PG45 after different culture periods: the number of <span class="html-italic">M. bovis</span> bacteria increased gradually with the passage of time, and there was a significant difference at 40 h compared to 32 h (<span class="html-italic">p</span> &lt; 0.05). (<b>C</b>) CFU of intracellular PG45 after different culture periods: <span class="html-italic">M. bovis</span> had a significant difference at 32 h (<span class="html-italic">p</span> &lt; 0.05) and an extremely significant difference at 40 h and 48 h compared to 0 h (<span class="html-italic">p</span> &lt; 0.01). * <span class="html-italic">p</span> &lt; 0.05; *** <span class="html-italic">p</span> &lt; 0.001.</p>
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<p>Invasion rates of four mycoplasma strains into various cell types. (<b>A</b>) PG45 exhibited the highest invasion rate in EBTr cells and the lowest in BT cells. (<b>B</b>) 08M. (<b>C</b>) 07801. (<b>D</b>) PG45-GFP. * <span class="html-italic">p</span> &lt; 0.05; ** <span class="html-italic">p</span> &lt; 0.01; NS, no significant difference (<span class="html-italic">p</span> &gt; 0.05).</p>
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<p>Invasion of four cell types by the PG45-GFP. (<b>A</b>) Laser confocal microscopy images of PG45-GFP strain invading MDBK, BT, EBL and EBTr cells. The red fluorescence represents the cytoplasm and cell membrane, the green fluorescence represents mycoplasma PG45-GFP, and the blue fluorescence represents the cell nucleus. (<b>B</b>) Quantification of intracellular green fluorescence intensity across the four cell types, revealing that the mean intracellular fluorescence intensity in EBTr cells was significantly higher compared to the other three cell types (<span class="html-italic">p</span> &lt; 0.01), while BT cells exhibited significantly lower mean intracellular fluorescence intensity (<span class="html-italic">p</span> &lt; 0.01). (<b>C</b>) Transmission electron microscopy images show PG45 invading various cells, with the white arrow indicating PG45 in the cytoplasm, the green arrow pointing to PG45 in endosomes, the red bidirectional arrow marking the cell membrane, and the yellow triangle denoting the nuclear membrane. *** <span class="html-italic">p</span> &lt; 0.001; NS, no significant difference (<span class="html-italic">p</span> &gt; 0.05).</p>
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<p>The process of PG45 invading EBL cells. (<b>A</b>) Laser confocal microscopy images capturing the invasion of EBL cells by PG45 at various time points. The red fluorescence represents the cytoplasm and cell membrane, the green fluorescence represents mycoplasma PG45-GFP, and the blue fluorescence represents the cell nucleus. (<b>B</b>) High-content video screenshots reveal that PG45 started adhering to the cell surface at 60 min, with significant adhesion and minor cytoplasmic entry at 90 min, which progressively increased over time. (<b>C</b>) Schematic diagram illustrating the intracellular positions of PG45, color-coded to show the gradual increase in PG45 over time. (<b>D</b>) 3D map of PG45 intrusion at 4 h, demonstrating the presence of green fluorescent PG45 within the yellow cytoplasm in all three views. (<b>E</b>–<b>J</b>) Sequential electron microscopy images showing the interaction between <span class="html-italic">M. bovis</span> and EBL cells: (<b>E</b>) Large numbers of <span class="html-italic">M. bovis</span> surrounding the cell membrane at 30 min; (<b>F</b>) PG45 beginning to bind tightly to the cell membrane at 60 min; (<b>G</b>) Cell membrane invagination induced by PG45 at 90 min; (<b>H</b>) PG45 entering the cell and residing in endosomes at 120 min; (<b>I</b>) PG45 located within intracellular vesicles at 180 min; (<b>J</b>) PG45 escaping from vesicles and residing in the cytoplasm at 240 min. The white arrow indicates PG45 in the cytoplasm, the green arrow indicates PG45 in the endocytic vesicles, and the blue arrow indicates PG45 escape from the endocytic vesicles, respectively, while the red bidirectional arrow denotes the cell membrane, and the yellow triangle represents the nuclear membrane.</p>
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<p>Detection of invasion rate, cell proliferation, and cytotoxicity following treatment with various agents. The horizontal axis represents the concentrations of different inhibitors, the left vertical axis represents cytotoxic effects, and the right vertical axis represents the invasion rate. Cell proliferation activity is negatively correlated with cytotoxicity. (<b>A</b>) The results obtained for EBL cells after treatment with different inhibitors, assessing invasion rate, cell proliferation, and cytotoxicity; (<b>B</b>) Similar assessments for EBTr cells; (<b>C</b>) MDBK cells; and (<b>D</b>) BT cells. The findings indicate a significant reduction in the invasion rates of all four cell types when treated with the inhibitor Chlorpromazine (CPZ) (<span class="html-italic">p</span> &lt; 0.01). Additionally, a significant decrease in the invasion rates of these cell types was observed when treated with the inhibitor Methyl-β-cyclodextrin (M-β-CD) at concentrations exceeding 4 µM (<span class="html-italic">p</span> &lt; 0.01). * <span class="html-italic">p</span> &lt; 0.05; ** <span class="html-italic">p</span> &lt; 0.01; *** <span class="html-italic">p</span> &lt; 0.001; ns, no significant difference (<span class="html-italic">p</span> &gt; 0.05).</p>
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<p>The results of intrusion rate detection for <span class="html-italic">M. bovis</span> following siRNA knockdown of CLR. (<b>A</b>) Assessment of the interference effects of CLR-1270 siRNA oligo on clathrin (CLR) in EBL cells, revealing that the optimal interference effect is achieved at a working concentration of 20 nM. (<b>B</b>) Following the siRNA knockdown of CLR, a significant decrease (<span class="html-italic">p</span> &lt; 0.001) was observed in the intrusion rates of <span class="html-italic">M. bovis</span> strains, specifically PG45, 07801, and 08M. *** <span class="html-italic">p</span> &lt; 0.001.</p>
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20 pages, 1427 KiB  
Review
Current Understanding of the Role of Autophagy in the Treatment of Myeloid Leukemia
by Yasushi Kubota and Shinya Kimura
Int. J. Mol. Sci. 2024, 25(22), 12219; https://doi.org/10.3390/ijms252212219 - 14 Nov 2024
Viewed by 377
Abstract
The most important issues in acute myeloid leukemia are preventing relapse and treating relapse. Although the remission rate has improved to approximately 80%, the 5-year survival rate is only around 30%. The main reasons for this are the high relapse rate and the [...] Read more.
The most important issues in acute myeloid leukemia are preventing relapse and treating relapse. Although the remission rate has improved to approximately 80%, the 5-year survival rate is only around 30%. The main reasons for this are the high relapse rate and the limited treatment options. In chronic myeloid leukemia patients, when a deep molecular response is achieved for a certain period of time through tyrosine kinase inhibitor treatment, about half of them will reach treatment-free remission, but relapse is still a problem. Therefore, potential therapeutic targets for myeloid leukemias are eagerly awaited. Autophagy suppresses the development of cancer by maintaining cellular homeostasis; however, it also promotes cancer progression by helping cancer cells survive under various metabolic stresses. In addition, autophagy is promoted or suppressed in cancer cells by various genetic mutations. Therefore, the development of therapies that target autophagy is also being actively researched in the field of leukemia. In this review, studies of the role of autophagy in hematopoiesis, leukemogenesis, and myeloid leukemias are presented, and the impact of autophagy regulation on leukemia treatment and the clinical trials of autophagy-related drugs to date is discussed. Full article
(This article belongs to the Special Issue The Role of Autophagy in Disease and Cancer)
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<p>Autophagy pathway. The membrane that forms at the contact site between the mitochondria and endoplasmic reticulum extends to surround the degradation products at both ends and closes (autophagosome). After that, it fuses with the lysosome to become an autolysosome, and the internal contents are broken down by digestive enzymes. Lysosomes are regenerated from the autolysosome.</p>
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<p>Formation of autophagosomes. The ULK1 complex, which is involved in the initiation of autophagy, is inhibited by the mTORC1 kinase complex, so autophagy is induced when TORC1 is inactivated by factors such as nutrient starvation. When the ULK1 complex migrates to a subdomain of the endoplasmic reticulum (ER), the PI3K complex I is recruited, and the production of PI3P production increases. The PI3P-binding protein WIPI binds to it and accumulates at the site of autophagosome formation together with its partner ATG2. ATG2 anchors the ER and the phagophore and transports lipids. The ATG12 system is a system in which ATG12 and ATG5 are covalently bound to each other via a ubiquitin-like binding reaction. The ATG12–ATG5 complex forms a ternary complex with ATG16L and localizes to the phagophore, where it determines the location of amide bond formation between ATG8 family proteins (LC3B) and PE. LC3B-PE localizes to the inner and outer membranes of the phagophore and autophagosome, and it functions in membrane elongation and closure. TORC1, target of rapamycin complex 1; ULK1, Unc51-like kinase 1; PI3K, phosphatidylinositol-3 kinase; PI3P, phosphatidylinositol-3-phosphate; WIPI, WD repeat domain phosphoinositide-interacting; ATG, autophagy-related protein; LC3B, light chain 3B; FIP200, focal adhesion kinase interacting protein; VPS34, vacuolar protein sorting 34.</p>
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<p>Effects of activating and inhibiting autophagy on leukemia cells. Although various anticancer drugs and radiation therapy have antitumor effects, they also activate autophagy in leukemia cells. This leads to resistance to antileukemia therapy and the progression of leukemia. It is thought that the use of autophagy inhibitors in combination can compensate for this drawback. However, drugs that promote autophagy are thought to promote the activation of autophagy beyond the maintenance of leukemia homeostasis, leading to cell death.</p>
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21 pages, 2627 KiB  
Review
Enhancing Cannabinoid Bioavailability in Pain Management: The Role of Cyclodextrins
by Adriana Ribeiro, Rui Loureiro and Helena Cabral-Marques
Molecules 2024, 29(22), 5340; https://doi.org/10.3390/molecules29225340 - 13 Nov 2024
Viewed by 670
Abstract
Chronic pain (CP), including pain related to cancer, affects approximately 2 billion people worldwide, significantly diminishing quality of life and imposing socio-economic burdens. Current treatments often provide limited relief and may cause adverse effects, demanding more effective alternatives. Natural compounds from Cannabis sativa [...] Read more.
Chronic pain (CP), including pain related to cancer, affects approximately 2 billion people worldwide, significantly diminishing quality of life and imposing socio-economic burdens. Current treatments often provide limited relief and may cause adverse effects, demanding more effective alternatives. Natural compounds from Cannabis sativa L., particularly cannabinoids like THC and CBD, exhibit analgesic and anti-inflammatory properties, but their therapeutic use is restricted by poor solubility and low bioavailability. Cyclodextrins (CDs) and cyclic oligosaccharides may encapsulate hydrophobic drugs in order to enhance their solubility and stability, offering a promising solution to these challenges. This study explores the formation of CD inclusion complexes with cannabinoids and specific terpenes, such as D-limonene (LIM), beta-caryophyllene (BCP), and gamma-terpinene (γ-TPN), aiming to improve pharmacokinetic profiles and therapeutic efficacy. We discuss analytical techniques for characterizing these complexes and their mechanisms of action, highlighting the potential of CDs to optimize drug formulations. The integration of CDs in cannabinoid therapies may enhance patient compliance and treatment outcomes in CP management. Future research should focus on innovative formulations and delivery systems to maximize the clinical applications of those compounds. Full article
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<p>Formation of host–guest inclusion complexes between <span class="html-italic">C. sativa</span> components and CDs, illustrating the glucose unit count (<span class="html-italic">n</span>), along with substitution sites (R<sub>2</sub>, R<sub>3</sub>, R<sub>6</sub>) for creating CD derivatives. Natural CDs; all R substituents are hydrogen atoms.</p>
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<p>Structure and dimensions of natural CDs, where n = 1, 2, or 3 represents α-, β-, or γ-CDs, and R<sub>2</sub>, R<sub>3</sub>, and R<sub>6</sub> can be substituted by different radicals to obtain CD-derivatives.</p>
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<p>Inclusion complexes involving cannabidiol (CBD) and CDs. This process entails (i) the displacement of water molecules from the hydrophobic cavity of the CD, allowing room for CBD; (ii) increased hydrogen bonding between the displaced water and the surrounding medium; (iii) minimized repulsive interactions between CBD and the aqueous environment; and (iv) strengthened hydrophobic interactions as CBD is fully encapsulated within the CD cavity. This mechanism enhances CBD’s bioavailability and therapeutic potential by protecting it from degradation and improving its solubility.</p>
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<p>CD inclusion complexes’ formation with cannabinoids and terpenes, highlighting the characterization.</p>
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25 pages, 1048 KiB  
Review
Cyclodextrins: Advances in Chemistry, Toxicology, and Multifaceted Applications
by Adina Magdalena Musuc
Molecules 2024, 29(22), 5319; https://doi.org/10.3390/molecules29225319 - 12 Nov 2024
Viewed by 746
Abstract
Cyclodextrins (CDs) have garnered significant attention in various scientific and industrial fields due to their unique ability to form inclusion complexes with a wide range of guest molecules. This review comprehensively explores the latest advancements in cyclodextrin chemistry, focusing on the synthesis and [...] Read more.
Cyclodextrins (CDs) have garnered significant attention in various scientific and industrial fields due to their unique ability to form inclusion complexes with a wide range of guest molecules. This review comprehensively explores the latest advancements in cyclodextrin chemistry, focusing on the synthesis and characterization of cyclodextrin derivatives and their inclusion complexes. This review examines the biological activities of cyclodextrins, highlighting their pharmacological properties and pharmacokinetics, and discussing their promising applications in drug delivery systems. Furthermore, the industrial utilization of cyclodextrins, including their role in nanomaterials and nanostructured coatings, as well as their potential in environmental remediation, are explored. The present research also addresses the critical aspect of toxicity, particularly concerning cyclodextrin inclusion complexes, providing an overview of the current understanding and safety considerations. Through a multidisciplinary approach, the aim is to present a complete view of cyclodextrins, underscoring their versatility and impact across various domains. Full article
(This article belongs to the Special Issue Cyclodextrin Chemistry and Toxicology III)
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<p>The general structure of CD (the figure represents the structure of the first three CDs: α-CD, β-CD, and γ-CD) [<a href="#B3-molecules-29-05319" class="html-bibr">3</a>].</p>
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<p>Schematic representation of the inclusion mechanism of a drug into the cyclodextrin cavity (adapted from [<a href="#B5-molecules-29-05319" class="html-bibr">5</a>]).</p>
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21 pages, 2160 KiB  
Review
How Do Cyclodextrins and Dextrans Affect the Gut Microbiome? Review of Prebiotic Activity
by Anna Gościniak, Emmanuelle Lainé and Judyta Cielecka-Piontek
Molecules 2024, 29(22), 5316; https://doi.org/10.3390/molecules29225316 - 11 Nov 2024
Viewed by 456
Abstract
The modulation of the gut microbiome through dietary components has garnered significant attention for its potential health benefits. Prebiotics, non-digestible food ingredients that promote the growth of beneficial gut bacteria, play a crucial role in maintaining gut health, enhancing immune function, and potentially [...] Read more.
The modulation of the gut microbiome through dietary components has garnered significant attention for its potential health benefits. Prebiotics, non-digestible food ingredients that promote the growth of beneficial gut bacteria, play a crucial role in maintaining gut health, enhancing immune function, and potentially preventing various metabolic and inflammatory disorders. This review explores the prebiotic activity of cyclodextrins and dextrans, focusing on their ability to influence gut microbiota composition and function. Both cyclodextrins and dextrans have demonstrated the capacity to promote the growth of beneficial bacterial populations, while also impacting short-chain fatty acid production, crucial for gut health. Full article
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<p>Scheme of prebiotics. TIM: The Netherlands Organization for Applied Scientific Research intestinal model, SHIME: simulator of the human intestinal microbial ecosystem, SCFAs: short-chain fatty acids, HPLC: High-performance liquid chromatography, GC: gas chromatography, HILIC: hydrophilic interaction liquid chromatography, LC–ESI–MS: liquid chromatography–electrospray ionization–mass spectrometry, RT-PCR: real-time polymerase chain reaction, qPCR: quantitative polymerase chain reaction, DGGE: denaturing gradient gel electrophoresis, T-RFLP: terminal restriction fragment length polymorphism, rRNA: ribosomal ribonucleic acid.</p>
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<p>Mechanism of action of prebiotics. SCFAs—Short-chain fatty acids.</p>
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<p>Chemical structure of main types of cyclodextrins.</p>
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<p>Structure of dextran.</p>
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17 pages, 1662 KiB  
Article
Kratom Alkaloids: A Blood–Brain Barrier Specific Membrane Permeability Assay-Guided Isolation and Cyclodextrin Complexation Study
by András Dohárszky, Erika Mária Vági, Árpád Könczöl, Alexandra Simon, Erzsébet Várnagy, Miras Muratov, Kristóf István Steiger, Bianka Várnai, Szabolcs Béni, Eszter Riethmüller and Ida Fejős
Molecules 2024, 29(22), 5302; https://doi.org/10.3390/molecules29225302 - 9 Nov 2024
Viewed by 730
Abstract
Mitragynine is an “atypic opioid” analgesic with an alternative mechanism of action and a favorable side-effect profile. Our aim was to optimize the alkaloid extraction procedure from kratom leaves and to determine and isolate the most relevant compounds capable of penetrating the central [...] Read more.
Mitragynine is an “atypic opioid” analgesic with an alternative mechanism of action and a favorable side-effect profile. Our aim was to optimize the alkaloid extraction procedure from kratom leaves and to determine and isolate the most relevant compounds capable of penetrating the central nervous system. The PAMPA-BBB study revealed that mitragynine and its coalkaloids, speciociliatine, speciogynine, and paynantheine, possess excellent in vitro BBB permeability. An optimized sequence of CPC, flash chromatography, and preparative HPLC methods was used to isolate the four identified BBB+ alkaloids. To improve the bioavailability of the isolated alkaloids, their cyclodextrin (CD) complexation behavior was investigated via affinity capillary electrophoresis using almost 40 CD derivatives. The apparent alkaloid–CD complex stability constants were determined and compared, and the most relevant CDs phase-solubility studies were also performed. Both the neutral and negatively charged derivatives were able to form complexes with all four kratom alkaloids. It was found that cavity size, substituent type, and degree of substitution also influenced complex formation. The negatively charged Sugammadex, Subetadex, and the sufoalkylated-beta-CD analogs were able to form the most stable complexes, exceeding 1000 M−1. These results serve as a good basis for further solubility and stability enhancement studies of kratom alkaloids. Full article
(This article belongs to the Section Natural Products Chemistry)
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<p>Comparison of the extraction procedures (Soxhlet extraction, maceration, ultrasound-assisted extraction (UAE), and supercritical CO<sub>2</sub> extraction (SFE)) applying methanol (MeOH) and ethanol (EtOH) regarding the yield and the mitragynine content of the extracts. Detailed results and further conditions can be found in <a href="#app1-molecules-29-05302" class="html-app">Table S2 (in the Supplementary Materials)</a> and in <a href="#sec3dot2-molecules-29-05302" class="html-sec">Section 3.2</a>.</p>
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<p>Demonstrative UHPLC-UV chromatogram of UAE MeOH (50 °C, 1:10 feed to solvent ratio) extract (red trace, top) and of PAMPA-BBB acceptor phase (green trace, bottom), along with the chemical structure of the kratom alkaloids detected in the acceptor phase recorded at 226 nm.</p>
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<p>(<b>a</b>) Schematic structure of the cyclodextrins (R stands for substituents), (<b>b</b>) representative electropherograms of mitragynine (M)–sulfobutyl-ether-β-cyclodextrin DS~6.5 complexes in the presence of increasing cyclodextrin concentrations using dimethyl sulfoxide as the electroosmotic flow (EOF) marker. Different colours indicate different cyclodextrin concentrations. Additional conditions can be found in <a href="#sec3dot7-molecules-29-05302" class="html-sec">Section 3.7</a>.</p>
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<p>A<sub>L</sub>- and A<sub>N</sub>-type isotherms of mitragynine–cyclodextrin complexes. Additional conditions and cyclodextrin abbreviations can be found in <a href="#sec3dot1-molecules-29-05302" class="html-sec">Section 3.1</a> and <a href="#sec3dot8-molecules-29-05302" class="html-sec">Section 3.8</a>. The R<sup>2</sup> values for each fitting are listed in <a href="#molecules-29-05302-t003" class="html-table">Table 3</a>.</p>
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15 pages, 3817 KiB  
Article
β-Cyclodextrin Functionalized Au@Ag Core-Shell Nanoparticles: Plasmonic Sensors for Cysteamine and Efficient Nanocatalysts for Nitrobenzene-to-Aniline Conversion
by Ramar Rajamanikandan, Kandasamy Sasikumar and Heongkyu Ju
Biosensors 2024, 14(11), 544; https://doi.org/10.3390/bios14110544 - 9 Nov 2024
Viewed by 690
Abstract
We reported the gold/silver core-shell nanoparticles (Aucore@Agshell NPs) functionalized with β-cyclodextrin (β-CD) as versatile nano-agents demonstrated for human urine-based biosensing of cysteamine and catalytic conversion from nitrobenzene (NB) to aniline. First, the hybrid bimetallic nanoparticles, i.e., β-CD-Aucore@Agshell [...] Read more.
We reported the gold/silver core-shell nanoparticles (Aucore@Agshell NPs) functionalized with β-cyclodextrin (β-CD) as versatile nano-agents demonstrated for human urine-based biosensing of cysteamine and catalytic conversion from nitrobenzene (NB) to aniline. First, the hybrid bimetallic nanoparticles, i.e., β-CD-Aucore@Agshell NPs, constituted a colorimetric sensing platform based on localized surface plasmons, enabling cysteamine (Cyst) to be detected in a remarkably rapid manner, i.e., within 2 min, which was greatly shortened in comparison with that of our previous report. This was due largely to use of β-CD being effectively replaceable by Cyst. The detection of Cyst was demonstrated using human urine specimens in the linear range of 25–750 nM with a limit of detection of 1.83 nM. Excellent specificity in detecting Cyst was also demonstrated against potential interfering molecules. Meanwhile, the β-CD-Aucore@Agshell NPs were demonstrated as nanocatalysts for converting NB to aniline with efficiency enhanced by more than three-fold over the pure gold nanoparticles previously reported, due to the dual functions of the structural core-shell. The demonstrated versatile features of the hybrid nanoparticles can find applications in human urine-based biosensors for Cyst detection, and in the screening of Cyst-containing drugs, while detoxicating NB for ecological protection in aqueous media. Full article
(This article belongs to the Special Issue Nanomaterial-Enhanced Biosensing for Point-of-Care Diagnostics)
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<p>Absorbance spectra (<b>a</b>) of β-CD-Au<sub>core</sub>@Ag<sub>shell</sub> NPs and β-CD-AuNPs while the inset shows the photo of freshly prepared β-CD-Au<sub>core</sub>@Ag<sub>shell</sub> NPs. (<b>b</b>) absorbance spectra of freshly prepared and 3-month-aged β-CD-Au<sub>core</sub>@Ag<sub>shell</sub> NPs while the insets of (i) and (ii) show the photos of freshly prepared and 3-month-aged β-CD-Au<sub>core</sub>@Ag<sub>shell</sub> NPs.</p>
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<p>Characteristics of β-CD-Au<sub>core</sub>@Ag<sub>shell</sub> (<b>a</b>) HR-TEM image. Inset of (<b>a</b>) shows a single β-CD-Au<sub>core</sub>@Ag<sub>shell</sub> NP (i) and the corresponding SAED pattern (ii). (<b>b</b>) XPS survey spectrum, (<b>c</b>) deconvoluted spectrum of XPS for Ag, and (<b>d</b>) deconvoluted spectrum of XPS for Au.</p>
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<p>Absorbance changes for β-CD-Au<sub>core</sub>@Ag<sub>shell</sub> NPs with various concentrations of Cyst in PBS (pH = 8.0). [Cyst] = (a) 0, (b) 25, (c) 50, (d) 75, (e) 100, (f) 200 (g) 300, (h) 400, (i) 500, and (j) 750 nM and the inset shows photographs of before (i) and after (ii) addition of (500 nM) Cyst into β-CD-Au<sub>core</sub>@Ag<sub>shell</sub> NPs.</p>
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<p>HR-TEM images of β-CD-Au<sub>core</sub>@Ag<sub>shell</sub> NPs that interacted with Cysts at different magnifications (<b>a</b>,<b>b</b>). Comparison between β-CD-Au<sub>core</sub>@Ag<sub>shell</sub> NPs that interacted with and without Cyst, by measurement of DLS (<b>c</b>) and Zeta potential (<b>d</b>).</p>
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<p>Calibration plot between the A<sub>602</sub>/A<sub>404</sub> and different concentrations of Cyst.</p>
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<p>Sensing specificity of the β-CD-Au<sub>core</sub>@Ag<sub>shell</sub> NPs to Cyst molecules against other interfering molecules such as uric acid (UA), dopamine (AA), ascorbic acid (AA), glutamate (Glu), arginine (Arg), asparagine (Asp), proline (Pro), alanine (Ala), glycine (Gly), histidine (His), Hcy, GSH, Met, and Cys in PBS (pH = 8.0).</p>
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<p>Time-evolution of absorbance spectra (<b>a</b>) representing the catalytic conversion of nitrobenzene to aniline using NaBH<sub>4</sub> with the nanocatalysts of β-CD-Au<sub>core</sub>@Ag<sub>shell</sub> NPs and the plot of the corresponding kinetics (<b>b</b>).</p>
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<p>Schematic representation of this study.</p>
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11 pages, 3908 KiB  
Article
Poly-Amino-β-Cyclodextrin Microparticles for the Reduction of Xenobiotics and Emerging Contaminants, Including Pharmaceuticals, from the Natural Environment
by Wojciech Ciesielski, Damian Kulawik, Beata Girek, Kinga Kozieł-Trąbska, Iwona Zawierucha and Tomasz Girek
Materials 2024, 17(22), 5424; https://doi.org/10.3390/ma17225424 - 6 Nov 2024
Viewed by 451
Abstract
The contamination of the natural environment by xenobiotics and emerging contaminants, including pharmaceuticals, poses significant risks to ecosystems and human health. Among these contaminants, hormones and pharmaceutical compounds are particularly concerning due to their persistence and potential biological effects even at low concentrations. [...] Read more.
The contamination of the natural environment by xenobiotics and emerging contaminants, including pharmaceuticals, poses significant risks to ecosystems and human health. Among these contaminants, hormones and pharmaceutical compounds are particularly concerning due to their persistence and potential biological effects even at low concentrations. In this study, we investigated the efficacy of poly-amino-β-cyclodextrin (PA-β-CD) microparticles in adsorbing and reducing specific xenobiotics and pharmaceuticals from aqueous solutions. Our research focused on four contaminants: two hormones, testosterone and progesterone, and two pharmaceutical drugs, diclofenac and carbamazepine. High-performance liquid chromatography (HPLC) was employed to quantify the adsorption capacity and efficiency of PA-β-CD microparticles. Full article
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<p>(<b>a</b>) Pictures of SAPAβCD microparticles (sodium alginate poly-amino-β-cyclodextrin) directly from the encapsulator and (<b>b</b>) at 40× zoom.</p>
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<p>Testosterone calibration curve.</p>
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<p>Progesterone calibration curve.</p>
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<p>Carbamazepine calibration curve.</p>
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<p>Diclofenac calibration curve.</p>
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<p>(<b>a</b>) Testosterone adsorption in the range pH 2–12 and (<b>b</b>) testosterone adsorption over time.</p>
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<p>(<b>a</b>) Progesterone adsorption in the range pH 2–12 and (<b>b</b>) progesterone adsorption over time.</p>
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<p>(<b>a</b>) Diclofenac adsorption in the range pH 2–12 and (<b>b</b>) diclofenac adsorption over time.</p>
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<p>(<b>a</b>) Carbamazepine adsorption in the range pH 2–12 and (<b>b</b>) carbamazepine adsorption over time.</p>
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