Label-free electrochemical aptasensor constructed by layer-by-layer technology for sensitive and selective detection of cancer cells

Anal Chim Acta. 2015 Jul 2:882:32-7. doi: 10.1016/j.aca.2015.05.008. Epub 2015 May 11.

Authors

Tianshu Wang¹, Jiyang Liu², Xiaoxiao Gu², Dan Li², Jin Wang³, Erkang Wang⁴

Affiliations

¹ College of Physics, Jilin University, Changchun, Jilin 130012, China; State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022, China.
² State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022, China.
³ College of Physics, Jilin University, Changchun, Jilin 130012, China; State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022, China; Department of Chemistry, Physics and Applied Mathematics, State University of New York at Stony Brook, Stony Brook, NY 11794-3400, USA. Electronic address: jin.wang.1@stonybrook.edu.
⁴ State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022, China. Electronic address: ekwang@ciac.jl.cn.

PMID: 26043089
DOI: 10.1016/j.aca.2015.05.008

Abstract

Here, a cytosensor was constructed with ferrocene-appended poly(allylamine hydrochloride) (Fc-PAH) functionalized graphene (Fc-PAH-G), poly(sodium-p-styrenesulfonate) (PSS) and aptamer (AS1411) by layer-by-layer assembly technology. The hybrid nanocomposite Fc-PAH-G not only brings probes on the electrode and also promotes electron transfer between the probes and the substrate electrode. Meanwhile, LBL technology provides more effective probes to enhance amplified signal for improving the sensitivity of the detection. While AS1411 forming G-quardruplex structure and binding cancer cells, the current response of the sensing electrode decreased due to the insulating properties of cellular membrane. Differential pulse voltammetry (DPV) was performed to investigate the electrochemical detection of HeLa cells attributing to its sensitivity of the current signal change. The as-prepared aptasensor showed a high sensitivity and good stability, a widely detection range from 10 to 10(6) cells/mL with a detection limit as low as 10 cells/mL for the detection of cancer cells.

Keywords: Cancer cells; Differential pulse voltammetry; Electrochemical aptasensor; Graphene-based nanocomposite; Layer-by-layer technology.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Electrochemical Techniques / instrumentation*
HeLa Cells
Humans
Microscopy, Confocal
Neoplasms / diagnosis
Neoplasms / pathology*
Sensitivity and Specificity