JPS59196455A - Glucose sensor - Google Patents

Abstract

PURPOSE:To determine degradation in function from color uniformity by a method wherein an enzyme for decomposing glucose, which enzyme has been previously assayed and approved to be uniform, is uniformly dispersed into Indian ink in a constant quantity to give a color. CONSTITUTION:A constant quantity of high-quality Indian ink with less mud content is taken, and a glucose decomposing enzyme such as fixative enzyme glucose oxidase, which performance has been already assayed, is added to the ink in a constant quantity and then kneaded. The Indian ink added with enzyme and kneaded uniformly is coated on a first ultrafiltration film 1 using a doctor knife in a thickness of 10mu and then suctioned from the back side to form a colored layer 2 in the first ultrafiltration film 1, the layer including the Indian ink with the enzyme. A second ultrafiltration film 3 is bonded on the surface containing the ink of the colored layer 2, as desired, and electrodes 4 formed of platinum for electrochemically measuring hydrogen peroxide are attached onto the surface containing no ink, thereby constituting a glucose sensor. The sensor thus constituted makes it possible to decide degradation in function at a glance.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a glucose sensor for measuring glucose in blood, plasma, etc., which exhibits uniform and constant performance.

The method of measuring the amount of glucose in blood, etc. using an oxidation reaction by glucose oxidase and measuring the hydrogen peroxide produced is a well-known method.
There are many ways to measure the hydrogen peroxide produced, such as chemical quantification, photochemical quantification, and electrochemical quantification. Recruitment 1- Can you do it? However-
The original glucose oxidase is currently commercially available as immobilized glucose oxidase, but mounting it as a sensor requires considerable technical knowledge and experience.

Moreover, there is a problem in that the crucose sensors manufactured in this way cannot always show the same performance.

This is especially true when a large number of samples must be measured over time and months, and when the data must be compared and examined.The present invention relates to improvements in this point. An enzyme that decomposes glucose, which has been tested and certified as uniform, is uniformly dispersed in a fixed amount of black ink, and the black colloid liquid is sucked into the ultrafiltration membrane from one side. When the suction is completed, the ultrafiltration membrane becomes uniformly black, and its uniformity can be determined based on its color. Next, an electrochemical hydrogen peroxide measuring electrode made of platinum is attached to the surface on which India ink is not applied first, and a sensor for measuring glucose is attached.

Note that C) is also good, in which a single ultrafiltration membrane is pasted on the upper surface of the side on which the ink was applied. In this case, an ultrafiltration membrane with a higher cutoff molecular weight may be used as the laminating membrane.

A specific example is shown below.

First measure the blackness of the resulting ink by using a high-quality ink with little mud on an inkstone. Next, a fixed amount of an enzyme that decomposes glucose, such as immobilized enzyme glucose oxidase, which has been purchased separately from a commercially available product and whose performance has been verified, is added to the mixture and thoroughly kneaded. The enzyme-containing ink liquid that has been kneaded into a uniform consistency is applied to the first ultrafiltration membrane to a thickness of 10 μm using a doctor knife.
As shown in Fig. 1, a colored layer 2 containing an enzyme layer is formed in the first ultrafiltration membrane 1 by suction from the back side, and a second ultrafiltration layer 7 is formed on the inked side. You may glue another filter membrane 6 together (sometimes you may not glue it together).
An electrode 4 for electrochemical hydrogen peroxide measurement made of platinum is attached to the unmarked surface to form a glucose sensor.

According to the present invention, whether or not the immobilized enzyme lucose oxidase is uniformly attached is determined by ink color, and 5 points are given.
There is an advantage that if the sensor malfunctions due to some kind of improper handling, you can determine the problem at a glance, and since there are many of the same ones, you can take the sensor over and over again. There is.

In addition, according to the present invention, the amount of glucose can be measured in a much shorter time than in the conventional method, as shown in FIG. 1 (indicated voltage on the vertical axis and time on the horizontal axis).

The figure is a graph showing the detection voltage of the glucose sensor according to the present invention.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing the configuration of a glucose sensor according to the present invention. FIG. 2 is a graph showing the detection voltage of the glucose sensor according to the present invention. 1...First ultrafiltration membrane, 2... Colored layer, 6
...Second ultrafiltration membrane, 4...Electrode.

Claims (1)

[Claims] In a glucose sensor having at least a first ultrafiltration membrane and an electrode, a colored layer containing an enzyme and a boundary is formed from one surface of the first ultrafiltration membrane to a depth that does not reach the other surface. 1. A glucose sensor, comprising: an electrode facing the surface of the first ultrafiltration membrane opposite to the colored layer.