JPH0959681A - Detergent for electrode for protein - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a detergent having weak oxidizing and reducing powers and useful for protein specimens by incorporating glycine into a neutral or alkaline aqueous solution. SOLUTION: This detergent is applied to, e.g. gold, silver, mercury, copper, aluminum, carbon, graphite, platinum or palladium electrodes used for various ionic electrode devices, a quartz resonator, a surface elastic wave device sensor, an electrochemical detector, stripping voltammetry, a pH meter, an ion-sensitized field effect transistor sensor, a coulometric titration apparatus, etc., can powerfully remove protein comprising an object specimen of, e.g. the blood serum, urine, body fluid, food or nutritious drink and adsorbed on the surfaces of the electrodes and can rapidly regenerate the electrodes. The aqueous glycine solution contains 0.02-3mol of glycine together with 0.01-1% assistant comprising a surface active agent, several percent of urea, and a proteolytic enzyme which is stable and active in an alkali. The electrodes used for measurement are repeatedly subjected to water washing, cleaning with the aqueous glycine solution and water washing.

Description

Detailed Description of the Invention

The present invention relates to a cleaning agent for various electrodes used in electrochemical measurement, sensors and the like.

[0002]

2. Description of the Related Art As a detergent for a sample containing protein,
Since a sufficient effect cannot be obtained with a surfactant, sodium hypochlorite, grincy hydrochloric acid buffer (pH 2.
5), enzymes such as pepsin and the like are used depending on the application. However, since sodium hypochlorite is a strong oxidant, its use is limited, and its cleaning is laborious. Also, other cleaning agents are less effective.

[0003]

[Problems to be Solved by the Invention] Oxidizing and reducing power is weak,
And, it relates to a detergent useful for protein samples.

[0004]

The present invention is characterized in that an aqueous glycine solution is used as a detergent for strongly removing the protein adsorbed on the electrode surface and rapidly regenerating the electrode.

In the present invention, as the sample, serum,
Urine, body fluids, foods, nutritional drinks, etc. are targeted. The electrodes are
Since glycine has a mild chemical property and a pH of about 8 to 9, it can be applied not only to gold electrodes, but also to silver, mercury, copper, aluminum, carbon, graphite, platinum, palladium electrodes and the like. As devices using these electrodes, various ion electrode devices, crystal oscillator sensors, surface acoustic wave device sensors, electrochemical detectors, stripping voltammetry, pH meters, ion-sensitized field effect transistor sensors, coulometric titrators, etc. is there.

The glycine aqueous solution is 0.02 mol-
3 mol, preferably 0.1 mol to 2 mol is excellent in detergency and handleability. Various surfactants may be coexistent in the glycine aqueous solution in an amount of 0.01 to 1% (desirably 0.1%), or a few percent of urea may be coexistent. In addition, an alkaline stable and active proteolytic enzyme (for example, protease) may coexist. Detergency is poor, but neutral to weak alkali (p
H6.5-8.0). In that case, the glycine content is preferably 0.1 mol or more.

The measured electrode is washed with water, then with a glycine solution, and then with water. This may be repeated twice or more. The glycine detergent has a function of rapidly removing proteins. Urea has a protein solubilizing effect,
Its speed is slow.

[0008]

Example 1 100 mg / dl arpmin sample 0.5
Take 3 ml in a test tube, add 2.5 g of 3 g / dl trichloroacetic acid and shake vigorously, 50 μl of that is placed on the electrode of Mutual Chemical Industries quartz crystal sensor SF (gold electrode, 9 MHz) and left for 3 minutes, The change in frequency was measured. Next, the electrode was washed with water and the sample was measured again. When this was repeated 6 times, no frequency change was observed, and it was found that the protein was irreversibly adsorbed on the gold electrode. Therefore, after washing with water, 1 mol glycine aqueous solution 5
0 μl was added, left for a few seconds and then washed with water. After repeating this operation, the sample was measured. As a result, the same frequency change as at the beginning appeared, and the electrode was completely regenerated.

[0009]

The electrode cleaning agent of the present invention has a mild chemical property and has a strong cleaning effect particularly on protein stains. Also, since the cleaning effect appears in a short time, it is excellent in quickness. Therefore, it is extremely useful in an apparatus of the type that performs many measurements in a short time.

Reference Example 1 In Example 1, after measuring the albumin solution twice, a blood gas analyzer ABL-5 manufactured by Radiometer
00 Rinse solution, 0.1 mol glycine solution, 0.2
Molar urea solution, 1 molar sodium hydroxide solution, 0.1 molar glycine-hydrochloric acid solution (pH 2.5) whereby the albumin solution was measured after washing. If the cleaning is insufficient, the frequency change is small. The results are shown in FIG. It can be seen that the detergency of the 0.1 mol glycine solution is extremely excellent.

[0010]

[Reference Example 2] Take 1 ml of serum as a sample in a beaker,
This is diluted 100 times with water. Toa Denpa's crawl measurement electrode (silver electrode), model ion electrode AG-12
5 was soaked in 0.3 mol glycine solution, then washed with water, put in a sample beaker, and chlorion ion was measured. Next, when the electrode was washed with water and then the chlor ion was measured again, the sensitivity was reduced by 30%. Therefore, when this electrode was washed with a 0.3 mol glycine aqueous solution and the chlor ion was measured again, the sensitivity was completely recovered.
Further, since there was no change in the initial potential of the crawl electrode, it can be seen that the crawl electrode made of silver sulfide had no effect.

[Brief description of drawings]

FIG. 1 shows the cleaning effect of an albumin sample and a urine sample attached to a gold electrode of a crystal oscillator sensor by various cleaning agents.

Claims (1)

[Claims] 1. An electrode cleaner comprising a neutral or alkaline aqueous solution containing glycine.