JPH0352574B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention belongs to the technical field of spectrophotometers capable of measuring the absorbance of a sample liquid.

[Technical background of the invention and its problems]

A conventional spectrophotometer, for example, a spectrophotometer installed in an automatic chemical analyzer, consists of a glass container (cell) containing a sample liquid, a light projection means for irradiating the cell with monochromatic light, and a sample liquid inside the cell. The absorbance of the sample liquid is measured by comparing the light intensity of the monochromatic light that does not pass through the sample liquid and the monochromatic light that passes through the sample liquid. It was configured so that it could be done.

In the spectrophotometer with the above configuration, the cell cannot be made as small as desired;
Even if miniaturization was achieved, at least 1 ml of sample liquid was required. Therefore, the spectrophotometer is not suitable for spectroscopic analysis of an ultra-trace amount of sample liquid of 1 ml or less.

Further, in the spectrophotometer having the above configuration, cleaning the cell was time-consuming and complicated. Furthermore, even if the cell is cleaned with great effort, it is difficult to completely clean the cell. Therefore, if the cell is used without being completely cleaned, contamination may cause errors in the spectroscopic analysis results. Furthermore, in order to completely clean the cell, a large amount of washing water is required, which is uneconomical.

[Purpose of the invention]

This invention was made in view of the above circumstances, and allows for spectroscopic analysis of ultra-trace amounts of sample liquid of 1 ml or less, as well as complete cleaning with a small amount of cleaning solution, resulting in accurate spectroscopic analysis. The purpose of this invention is to provide an ultra-trace spectrophotometer that can perform analysis.

[Summary of the invention]

The outline of this invention for achieving the above object is as follows:
a droplet holding means having a pair of supports arranged opposite to each other to hold the sample droplet by its surface tension;
It is characterized by comprising a droplet supply means for supplying a sample droplet into the gap between the pair of supports, and an absorbance measuring means for measuring the absorbance of the sample droplet held in the gap between the pair of supports. This is an ultra-trace spectrophotometer.

[Embodiments of the invention]

FIG. 1 is an explanatory diagram showing an embodiment of the present invention.

An ultra-trace spectrophotometer according to an embodiment of the present invention includes droplet holding means, droplet supply means, and absorbance measuring means.

As shown in FIG. 1, the droplet holding means holds the sample droplet 1A in the direction of gravity by its surface tension, and includes a pair of supports such as glass fibers 2A with their end surfaces facing each other. , 2B, the glass fiber 2A and the glass fiber 2
The sample droplet 1A is configured to be able to be held between the end faces of the sample droplet 1A and the sample droplet 1A. The distance X between the end faces of the glass fibers 2A and 2B can be appropriately determined depending on the amount of sample liquid to be held. For example, in order to hold a sample liquid of 30μ or less, glass fibers 2A, 2
It is preferable that the distance between the end faces of B is 4 mm or less.

The droplet supply means includes the glass fibers 2A, 2.
A device for supplying a sample liquid between the end faces of B, such as a sample container containing a sample (not shown).
After inserting the sample into the sample container and aspirating the sample liquid, the glass fibers 2A and 2B are moved from the sample container upward between the end faces of the glass fibers 2A and 2B.
After approaching between the end faces of 2B, a small amount of sample droplet 1B
The suction discharge nozzle 3A is connected to the suction discharge nozzle 3A and the suction discharge nozzle 3A discharges the
A syringe pump 3B that generates the suction pressure and discharge pressure of A and discharges the cleaning liquid from the suction and discharge nozzle 3A, a cleaning liquid container 3C that stores the cleaning liquid, and a flow path 3D that transports the cleaning liquid in the cleaning liquid container 3C. Equipped with a three-way socket 3E for switching the connection with the syringe pump 3B and the connection between the suction discharge nozzle 3A and the syringe pump 3B,
The sample droplet 1B and the cleaning liquid can be ejected between the end faces of the glass fibers 2A and 2B from the tip of the suction and ejection nozzle 3A. The inner diameter of the suction and discharge nozzle 3A can be appropriately determined depending on the volume of the sample droplet 1A held between the end faces of the glass fibers 2A and 2B.

The absorbance measurement means includes a light source (not shown), a slit 4A for converting light from the light source into a beam light, a spectroscopic element 4B for dispersing the white beam light incident through the slit 4A, and a light beam that is separated by the spectroscopic element 4B. A glass fiber 2A that guides monochromatic light and emits the monochromatic light to the sample droplet 1A held by the droplet holding means, and a glass that receives and guides the monochromatic light that has passed through the sample droplet 1A. Fiber 2B and
It is equipped with a photoelectric conversion element 4C that photoelectrically converts the monochromatic light guided by the glass fiber 2B, and a spectroscopic element 4 is attached to the sample droplet 1A held by the droplet holding means.
It is configured so that the absorbance of the sample liquid can be measured by irradiating monochromatic light separated by B and photoelectrically converting the monochromatic light that has passed through the sample droplet 1A with the photoelectric conversion element 4C. Note that the glass fibers 2A and 2B, which are one element of the absorbance measuring means,
also serves as a support in the droplet holding means.

The operation of the above configuration will be described next.

In the initial state, the suction/discharge nozzle 3A, the flow path 3D, and the syringe pump 3B are filled with cleaning liquid, and the plunger 3F of the syringe pump 3B is almost pushed into the syringe pump 3B. shall be taken as a thing.

Therefore, first, connect and communicate the syringe pump 3B and the suction discharge nozzle 3A by driving the three-way pot 3E, and then pull out the plunger 3F of the syringe pump 3B slightly to lower the liquid level of the cleaning liquid in the suction discharge nozzle 3A. let Then,
The suction/discharge nozzle 3A is inserted into a sample container (not shown) and immersed in the sample liquid. Then, by slightly pulling out the plunger 3F of the syringe pump 3B again, the sample liquid is sucked into the suction/discharge nozzle 3A. Thereafter, the suction/discharge nozzle 3A is moved from the sample container to above the end surfaces of the glass fibers 2A, 2B. In this case, the cleaning liquid and the sample liquid are held within the suction/discharge nozzle 3A via an air layer.

Next, by slightly pushing the plunger 3F in the syringe pump 3B, the sample liquid inside is pushed out from the tip opening of the suction/discharge nozzle 3A, and the sample liquid is poured into the tip opening of the suction/discharge nozzle 3A as shown in FIG. Hold drop 1B. While holding the glass fibers 2A and 2B, the suction and discharge nozzle 3A is lowered and brought close to between the end faces of the glass fibers 2A and 2B. When the sample droplet 1B held at the tip opening of the suction/discharge nozzle 3A comes into contact with the end faces of the glass fibers 2A, 2B, the sample droplet 1B moves between the end faces of the glass fibers 2A, 2B, and as shown in FIG. As shown in FIG. 3, it is held like a bridge between the end faces.

On the other hand, white light emitted from a light source (not shown) is turned into a white beam by the slit 4A, and this white beam is split into concave diffraction gratings 4B, and the split monochromatic light of a specific wavelength is incident on one end of the glass fiber 2A. , and propagate inside it.

The monochromatic light guided by the glass fiber 2A enters the sample droplet 1A held between the end faces of the glass fibers 2A and 2B, and after passing, enters the end face of the other glass fiber 2B. The monochromatic light propagated through the glass fiber 2B is converted into a current by the photoelectric conversion element 4C, and the absorbance is calculated by, for example, a digital arithmetic unit (not shown).

During absorbance measurement, the three-way pot 3E is driven to connect the flow path 3D and the syringe pump 3B, and the plunger 3F is pulled out to fill the syringe pump 3B with cleaning liquid. Next, after measuring the absorbance as described above, the three-way pot 3E is driven to connect the suction/discharge nozzle 3A and the syringe pump 3B, and the plunger 3F is pushed in to squirt the cleaning liquid from the tip opening of the suction/discharge nozzle 3A. , by pouring a cleaning liquid between the end faces of the glass fibers 2A, 2B.
Clean between the end faces of B.

Since the ultra-trace spectrophotometer is configured as described above, the amount of sample liquid used for measurement is, for example, 30μ.
It is possible to clean the end surfaces of the glass fibers 2A and 2B with a small amount of cleaning liquid.

Although one embodiment of the present invention has been described in detail above, the present invention is not limited to the above embodiment, and can be implemented with appropriate modifications within the scope of the gist of the invention. Needless to say.

A second embodiment is shown in FIG. 2.

The second embodiment differs from the previous embodiment in that the glass fibers 2A and 2B are configured to be able to vibrate in the direction of the arrow shown in FIG. 2, and that the glass fiber 2A emits white beam light from the other end. The glass fiber 2B
Propagates the white beam light that has passed through the sample droplet 1A held between the end faces of the glass fibers 2A and 2B, and emits it from the other end, and the other end of the glass fiber 2B is equipped with a spectroscopic element 4B. A photodiode array 4D is arranged, and after the white beam light emitted from the other end of the glass fiber 2B is split into each monochromatic light by a spectroscopic element, each monochromatic light is irradiated onto the photodiode array 4D. The structure is such that it is possible to measure the absorbance of monochromatic light of different wavelengths. glass fiber 2
When A and 2B are configured to be able to vibrate in the direction of the arrow shown in the figure, when the sample liquid is a mixture of a specimen and a reagent, sufficient mixing is performed by vibration, and the end faces of the glass fibers 2A and 2B are separated. The sample droplets held in the sample can be made uniform.
In addition, a white beam light is propagated through the glass fibers 2A and 2B, and a diffraction grating is arranged as a spectroscopic element 4B at the output end of the glass fiber 2B.
By configuring the photodiode array 4D to receive each of the monochromatic lights separated by B, the ultra-trace spectrophotometer can be made into an ultra-trace multi-wavelength spectrophotometer. However, in the above embodiment as well, the diffraction grating 4B is made rotatable by using the spectroscopic element 4B placed in front of the input end of the glass fiber 2A as a diffraction grating, so that monochromatic light with different wavelengths is sequentially transmitted to the input end of the glass fiber 2A. By allowing the light to enter, the ultra-trace spectrophotometer of the embodiment described above can also be used as an ultra-trace multi-wavelength spectrophotometer. However, the second
As in the embodiment, if the diffraction grating 4B is placed on the emission end side of the white beam light in the glass fiber 2B, multi-wavelength spectroscopic analysis can be performed using the photodiode array 4D without rotating the diffraction grating 4B. Therefore, the rotating device for the diffraction grating 4B can be omitted.

A third embodiment is shown in FIG. 3.

The third embodiment is different from the first embodiment in that the supports 2C and 2D, which are droplet holding means, are made of other members other than glass fibers, and the absorbance measuring means is A light reflector 4E formed on the end surface of the support 2D facing the support 2C, and an emitting end surface held by the support 2C and from which the light beam is emitted are exposed on the end surface of the support 2C facing the support 2D. The first glass fiber 2F is formed to A second glass fiber 2G is formed such that its end surface is exposed at the end surface of the support body 2C facing the support body 2D.

Further, as a fourth embodiment, the one shown in FIG. 4 can be cited.

The difference between the fourth embodiment and the first embodiment is that a pair of supports 2E and 2F are disposed facing each other and are made of a material other than glass fibers, and a beam light is emitted to form a sample droplet 1C. The pair of glass fibers 2H and 2I into which the transmitted beam light is incident are arranged so as to be orthogonal to each other within the same plane.

Furthermore, glass fibers 2A, 2 which are supports
By making it possible to spray the cleaning liquid from the gap B or the end faces of the supports 2C, 2D, 2E, and 2F, an ultra-trace spectrophotometer having a self-cleaning function can be obtained.

〔Effect of the invention〕

According to the invention described in detail above, it is possible to perform spectroscopic analysis of a sample even in an ultra-trace amount. Moreover, since the sample liquid used for analysis is in an ultra-trace amount, it is easy to separate it into each wavelength component, and the absorbance can be measured with high precision.The degree of contamination on the opposing surface of the support is minimal, and it is different from that in the case of a cell. In contrast, since contamination can be removed easily and quickly, analysis errors due to contamination can be prevented and accurate spectroscopic analysis can be performed at all times. Furthermore, since the sample liquid is held by surface tension in the direction of gravity, the sample liquid can be washed away with a small amount of washing water. Also,
Since the amount of sample liquid is small, the amount of washing water used can be significantly reduced.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing one embodiment of the invention, and FIGS. 2 to 4 are explanatory diagrams showing other embodiments of the invention. 1A, 1B, 1C...Sample droplet, 2A, 2B, 2
C, 2D, 2E, 2F...Support.

Claims (1)

[Claims] 1. A droplet holding means consisting of a pair of supports arranged opposite each other with a gap in the direction of gravity that holds the sample droplet by its surface tension, and a sample droplet and a cleaning liquid in the gap between the pair of supports. An ultrasonic device characterized by having a supply means for selectively supplying light, and an absorbance measuring means for supplying light from at least one of the supports to the gap and measuring the absorbance of a sample droplet held in the gap. Microvolume spectrophotometer.