An enzyme electrode and a biosensor and a measuring apparatus therewith

Claim 2

An enzyme electrode as claimed in Claim 1 where the vinyl polymer is a homopolymer or copolymer of one or more monomers selected from the group consisting of unsaturated hydrocarbons, unsaturated carboxylic acids and unsaturated alcohols.

Claim 3

An enzyme electrode as claimed in Claim 1 where the vinyl polymer is a polycarboxylic acid.

Claim 4

An enzyme electrode as claimed in Claim 1 where the fluoroalkylene block is attached to the vinyl polymer via an ester group.

Claim 5

An enzyme electrode as claimed in Claim 1 where the fluorine content represented by x/ (x+y) in the pendant group is 0.3 to 1, where x and y are the numbers of fluorine and hydrogen atoms in the pendant group, respectively.

Claim 6

An enzyme electrode as claimed in Claim 1 where the pendant group has 3 to 15 carbon atoms.

Claim 7

An enzyme electrode comprising an electrode on an insulating substrate, an immobilized enzyme layer on the electrode and a permeation restricting layer on the immobilized enzyme layer, said permeation restricting layer mainly consisting of a polycarboxylic acid (A) fluoroalcohol ester.

Claim 8

An enzyme electrode comprising an electrode on an insulating substrate, an immobilized enzyme layer on the electrode and a permeation restricting layer on the immobilized enzyme layer, said permeation restricting layer comprising a polycarboxylic acid (A) fluoroalcohol ester and a polycarboxylic acid (B) alkylalcohol ester.

Claim 9

An enzyme electrode as claimed in Claim 7 or 8 where the polycarboxylic acid (A) is polymethacrylic acid, polyacrylic acid or a copolymer of acrylic acid and methacrylic acid.

Claim 10

An enzyme electrode as claimed in Claim 7 or 8 where the fluorine content represented by x/(x+y) in the polycarboxylic acid (A) fluoroalcohol ester is 0.3 to 1, where x and y are the numbers of fluorine and hydrogen atoms in the fluoroalcohol ester, respectively.

Claim 11

An enzyme electrode as claimed in Claim 7 or 8 where the fluoroalcohol moiety in the polycarboxylic acid (A) fluoroalcohol ester has 3 to 15 carbon atoms.

Claim 12

An enzyme electrode as claimed in Claim 8 where the polycarboxylic acid (B) is polymethacrylic acid, polyacrylic acid or a copolymer of acrylic acid and methacrylic acid.

Claim 13

An enzyme electrode as claimed in Claim 8 where the polycarboxylic acid (B) alkylalcohol ester is the polycarboxylic acid (B) whose carboxyl groups are at least partially esterified with an alkylalcohol having 2 to 10 carbon atoms.

Claim 14

An enzyme electrode as claimed in Claim 8 where the polycarboxylic acid (B) alkylalcohol ester is cyclohexyl polymethacrylate.

Claim 15

An enzyme electrode comprising an electrode on an insulating substrate, an immobilized enzyme layer on the electrode and a permeation restricting layer on the immobilized enzyme layer, said permeation restricting layer mainly consisting of a polycarboxylate comprising alkylalcohol ester and fluoroalcohol ester groups.

Claim 16

An enzyme electrode as claimed in Claim 15 where the fluorine content represented by x/(x+y) in the fluoroalcohol ester group is 0.3 to 1, where x and y are the numbers of fluorine and hydrogen atoms in the fluoroalcohol ester group, respectively.

Claim 17

An enzyme electrode as claimed in Claim 15 where the fluoroalcohol moiety in the fluoroalcohol ester group has 3 to 15 carbon atoms.

Claim 18

An enzyme electrode as claimed in Claim 15 where the alkylalcohol ester group has 2 to 10 carbon atoms.

Claim 19

An enzyme electrode as claimed in Claim 15 where the alkylalcohol ester group is a cyclohexyl polymethacrylate moiety.

Claim 20

An enzyme electrode as claimed in Claim 1, 7, 8 or 15 where the permeation restricting layer has a thickness of 0.01 to 3 µm.

Claim 21

An enzyme electrode comprising: an electrode on an insulating substrate, an electrode protection layer comprising an urea compound covering at least a part of the electrode, and an immobilized enzyme layer covering the electrode and the electrode protection layer.

Claim 22

An enzyme electrode as claimed in Claim 21 where the urea compound is urea or thiourea.

Claim 23

An enzyme electrode as claimed in Claim 21 where the electrode is a platinum electrode.

Claim 24

An enzyme electrode as claimed in Claim 21 where the electrode protection layer is formed by soaking the insulating substrate with the electrode into a mixed solution comprising a supporting electrolyte and an urea compound while applying electricity.

Claim 25

An enzyme electrode as claimed in Claim 24 where the mixed solution contains 0.1 mM to 6.7 M of urea and 0.1 mM to 2M of sodium chloride.

Claim 26

An enzyme electrode as claimed in Claim 21 where a permeation restricting layer mainly consisting of a polymer in which a pendant group containing at least a fluoroalkylene block is attached to a non-fluorinated vinyl polymer is formed on the immobilized enzyme layer.

Claim 27

An enzyme electrode as claimed in Claim 26 where the polymer is a fluoroalcohol polycarboxylate.

Claim 28

A biosensor comprising an enzyme electrode as claimed in Claim 1, 7, 8, 15 or 21 as a working electrode.

Claim 29

A biosensor as claimed in Claim 28, which is used for measuring a glucose concentration in urine.

Claim 30

A measuring apparatus comprising a biosensor as claimed in Claim 28 or 29 and a data indicator indicating an electric signal from the biosensor.

Claim 31

A measuring apparatus comprising a biosensor as claimed in Claim 28 or 29, an electrochemical measuring circuit receiving an electric signal from the biosensor, a data processor calculating a measured value based on the electric signal, and a data indicator indicating the measured value.

Claim 32

A measuring apparatus as claimed in Claim 31 where the data processor comprises all or some of the following means; (a) a timer, (b) a time setting means for setting a time and a time indicator indicating a time at the time set by the time setting means, (c) an operation guide means describing operation instructions for the measuring apparatus, (d) a measured-value storing means for storing a calculated measured value, (e) a password registration means for registering a password for a user of the measuring apparatus, (f) a memo registration means for registering a memo, (g) an operation indicator for detecting malfunction in the measuring apparatus, (h) a calibration-timing indicator for detecting and indicating a calibration timing for the enzyme electrode, (i) an electrode-replacement-timing indicator for detecting and indicating a replacement timing for the enzyme electrode, (j) an abnormal-current indicator for detecting and indicating an abnormal current, and (k) an electrode calibrator for calibrating the enzyme electrode.

Claim 34

A method for manufacturing an enzyme electrode as claimed in Claim 33 where the second liquid is applied by spin coating.

Claim 35

A method for manufacturing an enzyme electrode as claimed in Claim 33 where the second liquid is applied by dipping and then the substrate is dried by nitrogen blowing.

Claim 36

A method for manufacturing an enzyme electrode as claimed in Claim 33 where the permeation restricting layer has a thickness of 0.01 to 3 µm after drying.

Claim 38

A method for manufacturing an enzyme electrode as claimed in Claim 37 where the supporting electrolyte is sodium chloride.

Claim 39

A method for manufacturing an enzyme electrode as claimed in Claim 38 where the mixed solution contains 0.1 mM to 6.7 M of urea and 0.1 mM to 2M of sodium chloride.