JPS58129245A - Selective membrane permeable to hydrogen peroxide - Google Patents

Abstract

PURPOSE:To obtain a strong membrane high in selective permeability to H2O2 for use in an H2O2 sensitive polarograph type enzymatic electrode, and easy to handle at the times of membrane formation, enzyme immobilization, and attachment to the electrode, by blending a vinyl type polymer with a cellulose ester type polymer. CONSTITUTION:A soln. contg. 0.1-10wt% vinyl type (co)polymer, such as polyvinyl acetate, ethylene-vinyl acetate copolymer, or polymethyl methacrylate, blended with 100wt% single or mixed esters of cellulose mono-, di-, or tri- acetate, propionate, nitrate, or the like is cast on a glass plate or the like in a constant thickness, and dried. It is immesed into water or a solvent nondissolving both of said polymers, such as n-hexane, taken out, dried, and stripped from the glass plate to obtain a membrane consisting of a dense layer and a porous material layer. This membrane is attached to an electrode as a selective membrane permeable to H2O2, thus permitting the obtained membrane to have high selective permeability to H2O2, high strength, and resistance to breakdown in handling, and to determined a slight amt. of glucose, uric acid, etc. accurately by immobilizing enzyme on the side of the porous layer.

Description

[Detailed description of the invention] Takaaki Tei is concerned with peroxide bulk selective permeation membranes.

An enzyme electrode composed of a combination of a peroxide volume-sensitive ILI Geralogteph electrode and an oxidoreductase that produces hydrogen peroxide as a result of an enzymatic reaction is used to measure various substances. For example, it is used in the measurement of glycose, galactose, sietapos, uric acid, cholesterol, phosphorus-11 moderate amino acids, alcohol, etc., and is used in food engineering, clinical testing, etc. as a wide chain cathode, with both electrodes When a constant voltage is applied to the seed AO chemical substance, a redox reaction occurs in one electrode field, a polarographic current proportional to the concentration of the redox substance is caused to flow, and this current is measured. For example, if a voltage of #cO @ 6 to 0.73 volts is applied between the two electrodes, a Melalog 7 electrode that is sensitive to the volume of monoperoxide can be obtained. Similar to hydrogen peroxide, sM-Ralogra 7 current can be detected for substances such as type glutathione and dithiothreitol.

Therefore, when trying to measure a trace component of interest, hydrogen persaponide is allowed to permeate in order to improve measurement accuracy by reducing positive interference by l-rap graphically active substances to a minimum of 11K, but other It is necessary to coat the Polar Tag 7 electrode with a concentrated material that has a selective permselectivity function that does not allow interfering substances to pass through.

On the other hand, in order to improve economical efficiency without repeatedly using expensive and unstable enzymes, a Kil stabilized membrane is used as an enzyme electrode in combination with the hydrogen peroxide-sensitive depolar p-grab electrode. In this case, it is important that the carrier for the carrier has sufficient mechanical strength to withstand one membrane forming process and one enzyme immobilization process as well as a permselective function for hydrogen peroxide.

Traditionally used chicken cellan (41 Kaisho AG-110
497, JP-A Sho@21-14009), cellulose acetate group (JP-A Shohiro, 1l-11$691),
Porous organic polymer membrane (Unexamined Japanese Patent Publication v8!1.8-1'F88e
No.), etc. are (a) have poor bulk permselectivity of peroxide water, and (b) are expensive, and (c) are porous. There are disadvantages such as (9) breakage when attached to the electrode due to excessive thickness, (1) low strength and difficulty in handling, and (e) complicated film doffing.

The purpose of the present invention is to provide a hydrogen peroxide sensitive m&-Ralogura 7 type membrane for bulk electrodes, which has high peroxide bulk permeability and peroxide bulk selective permeability, is easy to handle, and has sufficient susceptibility. The purpose of this invention was to provide a membrane that has mechanical strength and is suitable as a carrier for mackerel molded into mm. In other words, the present invention uses cellulose ester polymer and vinyl polyester! - It is a water peroxide bulk permselectivity consisting of.

The hydrogen oxide method of the present invention is a cell cost-ester-based lrimer and a vinyl-based poly! Blending - may impair the permselectivity of hydrogen peroxide. Furthermore, the oiaws-formed water selectively permeable membrane of the present invention has an asymmetric structure consisting of a dense layer and porosity, so that it can maintain a high water peroxide permselective function.

Cellulose ester type material used in the present invention! -Toha, cellulose monocetate, cellulose diacetate, cellulose triacetate, tatsuruta-supropionate,
cellulose p-stylate, cellulose cyanoethylenic acid,
Seven sitting one-s metatarylate, cellulose acrylate,
Nitrocellulose is the reaction product of camellia with organic # or IIIA-free # and cellulose. The cellulose ester-based final polymer may be a 19-mer of fjL with 2 or more esters, or a mixed ester polymer containing 2111 or more of the above ester parts in the same molecule.

Vinyl polymers used in the present invention include l-vinyl acetate, ethylene-vinyl acetate copolymer, polyvinylcyclohexane, polystyrene, polymethylstyrene, l-70
Examples include rostyrene, polyvinyl methyl ether, melivier-1-propyl ether, l-lymethyl methacrylate, polymethyl acrylate, poly-n-propyl methacrylate, and poly-octyl methacrylate.

Particularly preferred is vinyl acetate i or a copolymer of vinyl acetate, other vinyl threads, and O. Vinyl-based y IJ mom - There is no particular restriction on the molecular weight.

The mixing ratio of vinyl poly Y-0 is 0.1 to 1o*lk%, preferably 0.1 to 1o*lk%, based on the cellulose ester polymer.
1-1 Tumor volume ≦. If it exceeds 10% by weight, the hydrogen peroxide permeability is low and the mechanical strength cannot be improved. Also, if the tumor volume is less than 0.1, cellulose ester poly! - By improving the mechanical strength of the membrane, it will not get hot.

An example of the method for manufacturing the hydrogen peroxide selectively permeable membrane of the present invention includes 1-acetone, methyl acetate, methyl ethyl ketone,
1 in methylene chloride, 1,4-dioxane, isophorone, cyclohexanone, chloroform, methylene chloride/methanol (80/J!O), etc., or a mixed solvent thereof.
The cellulose ester poly! - and vinyl only! −
The dope is cast onto the mixture to a certain thickness using a coater. After air-drying for a certain period of time to evaporate the surface layer and form a dense layer, a large excess of water, n-hexane, etc. was blended. - Gently immerse in non-III medium common to. After several hours, the membrane is extracted and air-dried to obtain an asymmetric membrane consisting of a dense layer and a porous layer.

The peroxide bulk permeability hyperextender of the present invention has high peroxide bulk permeability and hydrogen hydrogen permeability selective permeability; It has been improved so that it is easy to handle and can be used alone as a hydrogen peroxide sensitive i1.
It is difficult to use it by attaching it to the 1&-Turograph electrode.

In addition, by making the membrane structure an asymmetric structure consisting of a dense layer and a porous layer, enzymes can be efficiently immobilized on the porous side with Daiyoshi ψ surface ridges as an immobilized enzyme membrane carrier for elementary electrodes. Flying.

Horseradish electricity using peroxide water bulk permeability error of the present invention l1l
iF! It is used in clinical analysis, food industry, ti1# industry, etc. as a sensor to accurately measure weight and cut quality.

A brief explanation will be given below using an example of winding a tube according to the present invention. This invention is
Each measurement item was determined according to the following method.

(a) A membrane permeable to water peroxide (Ysnioxidase, Probe, 2ISIO, Yellow Fist Springs, Instrument Company) was coated with a sample. This electrode is immersed in O, OIM acetate buffer solution 10-. After prewarming at 87°C for 5 minutes, 0.1
- Add standard hydrogen peroxide solution (0.01%) with stirring. After 1 minute, the steady current detected by the electrodes was measured. The peroxide peroxide bulk permeability was expressed in terms of the film thickness per 1 μm and the current value detected by the electrode. Membrane permeability of other electrode sensitive substances - This measurement method was followed.

(b) Tensile strength of membrane: 20°C, R11g using a Tensilon 0 type tensile tester.
5%, measured in WII air. The gauge length was 111, the tensile strength was 31 cm, and it was measured at 7 minutes.

Example L 7- To a mixed solvent of 60 parts of cyclohexane and 401S of cyclohexane, a 711 mixture of cellulose acetate or cellulose acetate and vinyl acetate (M+)! - was dissolved to prepare a 4% dope of the polymer.

The mixture was cast onto a horizontally held glass plate using a knife coater to a thickness of 100 μtmilc. After leaving it in air for several minutes, it was immersed in n-hexane to extract the solvent. After air drying, it was peeled off from the glass plate to obtain a white semipermeable membrane with a thickness of 7 μm. This membrane has an asymmetric structure consisting of a dense layer and a porous layer.

Figure 1 shows the hydrogen peroxide permeability and tensile strength of the obtained asymmetric membrane. As is clear from Figure 1, a membrane made of cellulose acetate blended with poly(1llI) + loose vinyl has superior tensile strength and strength without reducing hydrogen peroxide permeability compared to a membrane made of cellulose acetate alone. ing.

Example 2 The permeability of the hydrogen peroxide permeable membrane obtained in Example 1 to a mailographic electrode sensitive material (0,1N) was determined by Te1s. For comparison, the permeability of the porous collagen membrane was also measured.

The results are shown in Table 1.

As is clear from Table 1, the present invention 0 selectively permeates peroxide, but the porous collagen membrane also permeates peroxide, uric acid, ascorbic acid, and reduced daltathion. Permeation @ Practical Example Dulcose oxidase and Uricar 4 were each immobilized on the hydrogen peroxide permeable membrane obtained in Example 1 by the porous ilK glutaraldehyde crosslinking method or the chitosan entrapment method. An enzyme electrode was prepared by combining the peroxide bulk permeable polarographic electrode and the above-mentioned immobilized membrane.

Glutose in serum or whole blood using the enzyme electrode,
The concentration of uric acid was measured. It was possible to measure glucose 1 urine* with high accuracy (without interference from ascorbic acid, reduced glutathione, and other O-electron sensitive substances present in the blood).

[Brief explanation of the drawing]

1st gJ#i shows the peroxide bulk permeability and tensile strength of the hydrogen peroxide permeable membrane of the present invention. Patent applicant: Toyobo Co., Ltd. A, 1 Akane

Claims (1)

[Claims] Hydrogen peroxide selectively permeable membrane made of cellulose ester polymer and vinyl polymer