PROTECTIVE FILM MATERIAL FOR BIOSENSOR PROBE

Abstract

The present disclosure provides, as a film structure useful for a probe of a biosensor, a film structure comprising a detection layer including an analyte-responsive enzyme; and a protection film formed on the detection layer, in which the protection film includes alone poly(styrene-ran-4-vinylpyridine-ran-propyleneglycol methacrylate); or the protection film includes a copolymer mixture including poly(styrene-ran-4-vinylpyridine-ran-propyleneglycol methacrylate); and poly(4-vinylpyridine)-block-poly(C.sub.1-15 alkyl methacrylate), or poly(4-vinylpyridine-ran-2-hydroxyethyl methacrylate).

Claims

1-5. (canceled)

6. A protection film used in a probe for a biosensor, the protection film comprising poly(styrene-ran-4-vinylpyridine-ran-propyleneglycol methacrylate) represented by Formula (1): ##STR00010## where m represents an integer of 1 to 20; x, y, and z each represent mole fractions of three types of monomer units of styrene, 4-vinylpyridine, and propyleneglycol methacrylate, and satisfy a relationship x+y+z=100; and w represents a number average molecular weight.

7. A protection film used in a probe for a biosensor, the protection film comprising a copolymer mixture including: poly(styrene-ran-4-vinylpyridine-ran-propyleneglycol methacrylate) represented by Formula (1): ##STR00011## where m represents an integer of 1 to 20; x, y, and z each represent mole fractions of three types of monomer units of styrene, 4-vinylpyridine, and propyleneglycol methacrylate, and satisfy a relationship x+y+z=100; and w represents a number average molecular weight; and poly(4-vinylpyridine)-block-poly(C.sub.1-15 alkyl methacrylate) represented by Formula (2): ##STR00012## where R represents an alkyl group having 1 to 15 carbon atoms; p and q each represent repeating units of two types of monomer units of 4-vinylpyridine and C.sub.1-15 alkyl methacrylate; and w represents a number average molecular weight; or poly(4-vinylpyridine-ran-2-hydroxyethyl methacrylate) represented by Formula (3): ##STR00013## where s and t each represent mole fractions of two types of monomer units of 4-vinylpyridine and 2-hydroxyethyl methacrylate, and satisfy a relationship s+t=100; and w represents a number average molecular weight.

8. The protection film according to claim 6, wherein in Formula (1) the mole fraction x of styrene is 5 to 30% and a relationship of the mole fraction x of styrene, the mole fraction of y 4-vinylpyridine, and the mole fraction z of propyleneglycol methacrylate is x+y+z=100.

9. The protection film according to claim 8, wherein in Formula (1) the mole fraction x of styrene is 10 to 30%.

10. The protection film according to claim 9, wherein in Formula (1) the mole fraction x of styrene is 5 to 25%.

11. The protection film according to claim 6, wherein in Formula (1) the mole fraction y of 4-vinylpyridine is 45 to 60% and a relationship of the mole fraction x of styrene, the mole fraction y of 4-vinylpyridine, and the mole fraction z of propyleneglycol methacrylate is x+y+z=100.

12. The protection film according to claim 9, wherein in Formula (1) the mole fraction y of 4-vinylpyridine is 50 to 60%.

13. The protection film according to claim 6, wherein in Formula (1) the mole fraction z of propyleneglycol methacrylate is 15 to 30% and a relationship of the mole fraction x of styrene, the mole fraction y of 4-vinylpyridine, and the mole fraction z of propyleneglycol methacrylate is x+y+z=100.

14. The protection film according to claim 9, wherein in Formula (1) the mole fraction x of propyleneglycol methacrylate is 20 to 25%.

15. The protection film according to claim 6, wherein the number average molecular weight of the polymer represented by Formula (1) is 40 to 8010.sup.3.

16. The protection film according to claim 6, wherein the number average molecular weight of the polymer represented by Formula (1) is 45 to 6010.sup.3.

17. The film structure according to claim 6, wherein the protection film further includes poly(2-methoxyethylacrylate).

18. The protection film according to claim 7, wherein in Formula (1) the mole fraction x of styrene is 5 to 30% and a relationship of the mole fraction x of styrene, the mole fraction of y 4-vinylpyridine, and the mole fraction z of propyleneglycol methacrylate is x+y+z=100.

19. The protection film according to claim 18, wherein in Formula (1) the mole fraction x of styrene is 10 to 30%.

20. The protection film according to claim 19, wherein in Formula (1) the mole fraction x of styrene is 5 to 25%.

21. The protection film according to claim 7, wherein in Formula (1) the mole fraction y of 4-vinylpyridine is 45 to 60% and a relationship of the mole fraction x of styrene, the mole fraction y of 4-vinylpyridine, and the mole fraction z of propyleneglycol methacrylate is x+y+z=100.

22. The protection film according to claim 19, wherein in Formula (1) the mole fraction y of 4-vinylpyridine is 50 to 60%.

23. The protection film according to claim 7, wherein in Formula (1) the mole fraction z of propyleneglycol methacrylate is 15 to 30% and a relationship of the mole fraction x of styrene, the mole fraction y of 4-vinylpyridine, and the mole fraction z of propyleneglycol methacrylate is x+y+z=100.

24. The protection film according to claim 19, wherein in Formula (1) the mole fraction x of propyleneglycol methacrylate is 20 to 25%.

25. The protection film according to claim 7, wherein the number average molecular weight of the polymer represented by Formula (1) is 40 to 8010.sup.3.

26. The protection film according to claim 7, wherein the number average molecular weight of the polymer represented by Formula (1) is 45 to 6010.sup.3.

27. The protection film according to claim 7, wherein the number average molecular weight of each block constituting the polymer represented by Formula (2) is 50 to 20010.sup.3.

28. The protection film according to claim 7, wherein the number average molecular weight of each block constituting the polymer represented by Formula (2) is 65 to 10010.sup.3.

29. The protection film according to claim 7, wherein in Formula (3) the mole fraction s of 4-vinylpyridine is 40 to 80, and a relationship of the mole fraction s of 4-vinylpyridine, and the mole fraction t of 2-hydroxyethyl methacrylate is s+t=100.

30. The protection film according to claim 29, wherein in Formula (3) the mole fraction s of 4-vinylpyridine is 60 to 70.

31. The protection film according to claim 7, wherein in Formula (3) the mole fraction t of 4-vinylpyridine is 20 to 60, and a relationship of the mole fraction s of 4-vinylpyridine, and the mole fraction t of 2-hydroxyethyl methacrylate is s+t=100.

32. The protection film according to claim 31, wherein in Formula (3) the mole fraction t of 2-hydroxyethyl methacrylate is 30 to 40.

33. The protection film according to claim 29, wherein in Formula (3) the mole fraction t of 4-vinylpyridine is 20 to 60, and a relationship of the mole fraction s of 4-vinylpyridine, and the mole fraction t of 2-hydroxyethyl methacrylate is s+t=100.

34. The protection film according to claim 33, wherein in Formula (3) the mole fraction t of 2-hydroxyethyl methacrylate is 30 to 40.

35. The protection film according to claim 30, wherein in Formula (3) the mole fraction t of 4-vinylpyridine is 20 to 60, and a relationship of the mole fraction s of 4-vinylpyridine, and the mole fraction t of 2-hydroxyethyl methacrylate is s+t=100.

36. The protection film according to claim 35, wherein in Formula (3) the mole fraction t of 2-hydroxyethyl methacrylate is 30 to 40.

37. The film structure according to claim 7, wherein the protection film further includes poly(2-methoxyethylacrylate).

38. A probe for a biosensor, the probe comprising: a working electrode; a reference electrode; and a counter electrode; a detection layer formed on the working electrode; and a protection film covering the working electrode, wherein the detection layer includes an analyte-responsive enzyme and a redox mediator; and the protection film includes poly(styrene-ran-4-vinylpyridine-ran-propyleneglycol methacrylate) represented by Formula (1): ##STR00014## where m represents an integer of 1 to 20; x, y, and z each represent mole fractions of three types of monomer units of styrene, 4-vinylpyridine, and propyleneglycol methacrylate, and satisfy the relationship x+y+z=100; and w represents a number average molecular weight.

39. A probe for a biosensor, the probe comprising: a working electrode; a reference electrode; and a counter electrode; a detection layer formed on the working electrode; and a protection film covering the working electrode, wherein the detection layer includes an analyte-responsive enzyme and a redox mediator; and the protection film includes a copolymer mixture including: poly(styrene-ran-4-vinylpyridine-ran-propyleneglycol methacrylate) represented by Formula (1): ##STR00015## where m represents an integer of 1 to 20; x, y, and z each represent mole fractions of three types of monomer units of styrene, 4-vinylpyridine, and propyleneglycol methacrylate, and satisfy a relationship x+y+z=100; and w represents a number average molecular weight; and poly(4-vinylpyridine)-block-poly(C.sub.1-15 alkyl methacrylate) represented by Formula (2): ##STR00016## where R represents an alkyl group having 1 to 15 carbon atoms; p and q each represent repeating units of two types of monomer units of 4-vinylpyridine and C.sub.1-15 alkyl methacrylate; and w represents a number average molecular weight; or poly(4-vinylpyridine-ran-2-hydroxyethyl methacrylate) represented by Formula (3): ##STR00017## where s and t each represent mole fractions of two types of monomer units of 4-vinylpyridine and 2-hydroxyethyl methacrylate, and satisfy a relationship s+t=100; and w represents a number average molecular weight.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0032] FIG. 1 is a schematic view illustrating a state where an embedded-type biosensor is attached to a living body (human body).

[0033] FIG. 2 is a cross-sectional view illustrating an embedded-type biosensor in a state of being attached to a living body (human body).

[0034] FIG. 3 is a schematic view of an embedded-type biosensor that performs wireless communication of measurement data with a smartphone.

[0035] FIGS. 4a and 4b show a production step of a probe of an embedded-type biosensor as a specific example of the present disclosure.

[0036] FIGS. 5c to 5e show a production step of a probe of an embedded-type biosensor as a specific example of the present disclosure.

[0037] FIGS. 6f and 6g show a production step of a probe of an embedded-type biosensor as a specific example of the present disclosure.

[0038] FIG. 7 is a top view on a front side of a probe of an embedded-type biosensor as a specific example of the present disclosure.

[0039] FIG. 8 is a cross-sectional view taken along the line A-A of FIG. 7.

[0040] FIG. 9 is a cross-sectional view taken along the line B-B of FIG. 8.

[0041] FIG. 10 is a cross-sectional view taken along the line C-C of FIG. 8.

[0042] FIG. 11 shows graphs showing glucose response characteristics of probes in which the copolymers of the present disclosure are used for a protection film.

[0043] FIG. 12 shows graphs showing durability of probes in which the copolymers of the present disclosure are used for a protection film.

[0044] FIG. 13 shows graphs showing glucose response characteristics of probes in which the copolymer mixtures of the present disclosure are used for a protection film.

[0045] FIG. 14 shows graphs showing durability of probes in which the copolymer mixtures of the present disclosure are used for a protection film.

[0046] FIG. 15 shows graphs showing glucose response characteristics of probes in which the copolymer mixtures of the present disclosure are used for a protection film.

[0047] FIG. 16 shows graphs showing durability of probes in which the copolymer mixtures of the present disclosure are used for a protection film.

[0048] FIG. 17 shows graphs showing glucose response characteristics of probes in which the polymers of Comparative Examples are used for protection film.

[0049] FIG. 18 shows graphs showing durability of probes in which the polymers of Comparative Examples are used for a protection film.

[0050] FIG. 19 shows graphs showing glucose response characteristics of probes in which the polymers of Reference Examples are used for a protection film.

[0051] FIG. 20 shows graphs showing durability of probes in which the polymers of Reference Examples are used for a protection film.

MODES FOR CARRYING OUT THE INVENTION

[0052] 1. Production Method of Probe of Embedded-Type Biosensor

[0053] A production method of a probe 11 of an embedded-type biosensor 1, to which the film structure of the present disclosure is applied, will be described as a specific example. The structure and production method described below are one of specific examples of the present disclosure, and are not limited to the features described below as long as it can be used as a probe.

[0054] (1) Preparation of Insulating Substrate

[0055] The embedded-type biosensor 1 includes a main body 10 and a probe 11. The probe 11, having a key shape, generally includes a sensing part to be inserted in a living body, and a terminal part to be electrically connected with an internal circuit of the biosensor main body 10. The sensing part is formed thin so as to be inserted in the body, and the terminal part has a certain size so as to be inserted in the biosensor main body 10 and establish electrical connection. Therefore, an insulating substrate 111 having a key shape is prepared firstly (FIG. 4a). In the upper part, a top view from the front side is shown, while in the lower part, a top view from the back side is shown (the same applies hereafter). This insulating substrate 111 is not particularly limited as long as it is made from a material and has a thickness that can be used as a probe to be inserted in the living body. For example, polyethylene terephthalate (PET) with a thickness of approximately 200 m can be used.

[0056] (2) Formation of Conductive Thin Film

[0057] A conductive thin film 112 is formed by depositing carbon or a conductive metal material selected from the group consisting of metals such as gold, silver, platinum, and palladium on both sides of the insulating substrate 111 by sputtering, deposition, ion plating, or the like (FIG. 4b). The thickness of the conductive thin film is preferably 10 nm to several hundred nm.

[0058] (3) Formation of Electrode Lead

[0059] A groove 113 is formed with a depth that reaches the surface of the insulating substrate 111 by performing laser drawing on the conductive thin film 112 formed on the front side of the insulating substrate 111. The groove 113 separates a working electrode lead 112a and a reference electrode lead 112b and thus electrically insulates them from each other (FIG. 5c).

[0060] (4) Formation of Insulating Resist Film

[0061] On the front side of the insulating substrate 111, an insulating resist film 116a having an opening is formed in a part excluding regions used for a working electrode 114 and a reference electrode 115 as well as a working electrode terminal 114a and a reference electrode terminal 115a to be electrically connected with the main body 10, by sputtering, screen printing, or the like. On the back side of the insulating substrate 111, an insulating resist film 116b having an opening is formed in a part excluding regions used for a counter electrode 117 and a counter electrode terminal 117a to be electrically connected with the main body 10, by sputtering, screen printing, or the like (FIG. 5d). The thickness of the insulating resist film is preferably 5 to 40 m.

[0062] (5) Formation of Reference Electrode

[0063] The reference electrode 115 is formed by depositing Ag/AgCl in the opening for the reference electrode of the resist film 116a formed on the front side of the insulating substrate 111 by screen printing or an inkjet method (FIG. 5e). The thickness of the reference electrode is preferably 5 to 40 m.

[0064] (6) Formation of Detection Layer

[0065] A detection layer 118 including conductive particles, an analyte-responsive enzyme, and a redox mediator is formed by applying a suspension of conductive particles such as carbon particles, an aqueous solution of the analyte-responsive enzyme, and an aqueous solution of the redox mediator on the working electrode 114 and dried them (FIG. 6f). In the present disclosure, the analyte-responsive enzyme refers to a biochemical substance that can specifically catalyze oxidization or reduction of an analyte. Any biochemical substance can be employed if it can be used for the purpose of detection in a biosensor. For example, in a case where glucose is used as an analyte, an appropriate analyte-responsive enzyme is glucose oxidase (GOx), glucose dehydrogenase (GDH), or the like. The redox mediator refers to a redox substance that mediates electron transfer, and plays a role in transferring electrons generated via redox reaction of the analyte in a biosensor. For example, examples of the redox mediator include, but are not limited to, a phenazine derivative, and any redox substance may be used as long as it can be used for the purpose of detection in a biosensor. The thickness of the detection layer is preferably 5 to 80 m.

[0066] (7) Formation of Protection Film

[0067] A protection film 119 is formed on the both surfaces, side surfaces, and tip of the sensing part by immersing the sensing part in a solution including a polymer for a protection film (FIG. 6g). The protection film 119 does not cover the working electrode terminal 114a, the reference electrode terminal 115a, and the counter electrode terminal 117a, but covers at least the working electrode 114, the reference electrode 115, the counter electrode 117, and the detection layer 118. The protection film 119 is formed with a length equal to or longer than the length inserted in the living body. The thickness of the protection film is preferably 5 to 200 m.

[0068] 2. Internal Structure of Probe of Embedded-Type Biosensor

[0069] The internal structure of the probe of an embedded-type biosensor, to which the film structure of the present disclosure is applied, will be further described.

[0070] FIG. 8 is a cross-sectional view taken along the line A-A of FIG. 7. The conductive thin film 112 is formed on the both sides of the insulating substrate 111. In the conductive thin film 112 on the front side of the insulating substrate 111, two leads of the working electrode lead 112a and the reference electrode lead 112b are separated and electrically insulated by the groove 113. A part of the working electrode lead 112a functions as the working electrode 114, and the detection layer 118 is formed on the working electrode 114. The reference electrode 115 is formed in the opening part of the insulating resist film 116a, and is electrically connected with the reference electrode lead 112b. The conductive thin film 112 on the back side of the insulating substrate 111 is a counter electrode lead 112c, and a part of the counter electrode lead 112c functions as the counter electrode 117.

[0071] FIG. 9 is a cross-sectional view taken along the line B-B of FIG. 8. The working electrode 114 is formed on the front side of the insulating substrate 111, and the detection layer 118 is formed on the working electrode 114. The counter electrode 117 is formed on the back side of the insulating substrate 111. Furthermore, FIG. 9 shows that the entire periphery of the sensing part is covered by the protection film 119 of the present disclosure.

[0072] FIG. 10 is a cross-sectional view taken along the line C-C of FIG. 8. The working electrode lead 112a and the reference electrode lead 112b, which are electrically separated by the groove 113, are formed on the front side of the insulating substrate 111. The insulating resist film 116a is formed on the working electrode lead 112a and the reference electrode lead 112b. The reference electrode 115 is formed in the opening part of the insulating resist film 116a. The counter electrode lead 112c is formed on the back side of the substrate 111, and the insulating resist film 116b is formed on the counter electrode lead 112c. Furthermore, FIG. 9 shows that the entire periphery of the sensing part is covered by the protection film 119 of the present disclosure.

EXAMPLES

Example 1

[0073] <Production of Probe>

[0074] (1) Preparation of Insulating Substrate

[0075] As shown in FIG. 5a, polyethylene terephthalate (PET), (Lumirror R E20, #188, available from Toray Industries, Inc., 189 m thick) was cut to prepare an insulating substrate having a key shape.

[0076] (2) Formation of Conductive Thin Film

[0077] As shown in FIG. 5b, a conductive thin film (thickness: 30 nm) was formed by depositing gold on both sides of an insulating substrate by sputtering.

[0078] (3) Formation of Electrode Lead

[0079] As shown in FIG. 5c, a groove was formed with a depth that reaches the surface of the insulating substrate by performing laser drawing on the conductive thin film formed on the front side of the insulating substrate, thus separating and electrically insulating a working electrode lead and a reference electrode lead.

[0080] (4) Formation of Insulating Resist Film

[0081] As shown in FIG. 5d, on the front side of the insulating substrate, an insulating resist film having an opening was formed in a part excluding regions used for the working electrode and the reference electrode as well as a working electrode terminal and a reference electrode terminal to be electrically connected with a main body of an embedded-type biosensor by screen printing. On the back side of the insulating substrate, an insulating resist film (thickness: 10 to 15 m) having an opening was formed in a part excluding regions used for a counter electrode and a counter electrode terminal to be electrically connected with the main body by screen printing.

[0082] (5) Formation of Reference Electrode

[0083] As shown in FIG. 5e, a reference electrode (thickness: 10 to 15 m) was formed by depositing Ag/AgCl in the opening for the reference electrode of the resist film formed on the front side of the insulating substrate by screen printing.

[0084] (6) Formation of Detection Layer

[0085] As shown in FIG. 6f, a conductive thin film that is exposed from the opening part of the insulating resist film formed on the front side of the insulating substrate was determined to be a working electrode, and a detection layer (thickness: 15 m) was formed by applying appropriate amounts of a suspension of carbon particles as conductive particles, an aqueous solution of glucose oxidase (GOx) as an analyte-responsive enzyme for glucose, and an aqueous solution of a phenazine derivative as a redox mediator and drying them.

[0086] (7) Formation of Protection Film

[0087] As shown in FIG. 6g, a protection film (thickness: 5 to 40 m) was formed on the both surfaces, side surfaces, and tip of the sensing part by immersing the sensing part in an ethanol solution containing a crosslinking agent and a polymer for a protection film.

[0088] More specifically, the probe produced as described above was immersed 6 times at 10 minutes intervals in a solution in which 600 mg of poly(styrene-ran-4-vinylpyridine-ran-propyleneglycol methacrylate) (M.sub.w/M.sub.n=1.8, m=2) [copolymer (4)] represented by Formula (4):

##STR00004##

and 47 mg of polyethylene glycol diglycidyl ether (PEGDGE) (Mn=1000) as a crosslinking agent were dissolved in 1 mL of a solvent (ethanol 95%, 4-(2-hydroxyethyl)-1-piperazine ethanesulfonic acid (HEPES) buffer solution (10 mM, pH 8) 5%). Thereafter, the probe was dried over 48 hours at room temperature to form a crosslinked protection film, and thereby a probe A was obtained. The formation conditions of the above-described protection film were summarized in Table 1.

[0089] <Measurement of Probe Characteristics>

[0090] [Glucose Response Characteristics]

[0091] The probe A was attached to an embedded-type amperometric glucose sensor, and then the probe was placed in a phosphate-buffered saline solution (PBS, pH 7) at 37 C. To the PBS solution, 50, 100, 200, 300, 400, and 500 mg/dL of glucose was added every 500 seconds in the order of amounts described, and the current response value (nA) was continuously measured.

[0092] High linearity was shown at a glucose concentration of 0 to 500 mg/dL, and glucose response was favorable. The result is shown in FIG. 11 and summarized in Table 2.

[Durability]

[0093] The probe A was stored in a phosphate-buffered saline solution (PBS, pH 7) at 37 C. The probe A was attached to an embedded-type amperometric glucose sensor before storage (day 0) and 7 days after storage, and the probe was placed in a phosphate-buffered saline solution (PBS, pH 7) at 37 C. To the PBS solution, 50, 100, 200, 300, 400, and 500 mg/dL of glucose was added every 500 seconds in the order of amounts described, and the current response value (nA) was continuously measured. The response ratio (%) at each concentration was calculated as the current response value at a glucose concentration of 500 mg/dL on day 0 being 100%.

[0094] Response characteristics 7 days after storage showed high linearity at a glucose concentration of 0 to 500 mg/dL and showed almost no change compared to day 0, and durability was favorable. The result is shown in FIG. 12 and summarized in Table 2.

Example 2

[0095] <Production of Probe>

[0096] In the formation of the protection film, a probe was produced in the same manner as in Example 1, except for changing polymers for a protection film.

[0097] More specifically, the probe produced in Example 1 was immersed 6 times at 10 minutes intervals in a solution in which 600 mg of poly(styrene-ran-4-vinylpyridine-ran-propyleneglycol methacrylate) (M.sub.w/M.sub.n=1.6, m=about 16) [copolymer (5)] represented by Formula (5):

##STR00005##

and 47 mg of polyethylene glycol diglycidyl ether (PEGDGE) (Mn=1000) as a crosslinking agent were dissolved in 1 mL of a solvent. Thereafter, the probe was dried over 48 hours at room temperature to form a crosslinked protection film, and thereby a probe B was obtained. The formation conditions of the above-described protection film were summarized in Table 1.

[0098] <Measurement of Probe Characteristics>

[0099] [Glucose Response Characteristics]

[0100] The glucose response characteristics of the probe B was measured in the same manner as in Example 1.

[0101] High linearity was shown at a glucose concentration of 0 to 500 mg/dL, and glucose response was favorable. The result is shown in FIG. 11 and summarized in Table 2.

[0102] [Durability]

[0103] The durability of the probe B was measured in the same manner as in Example 1.

[0104] Response characteristics 7 days after storage showed high linearity at a glucose concentration of 0 to 500 mg/dL and showed almost no change compared to day 0, and durability was favorable. The result is shown in FIG. 12 and summarized in Table 2.

Example 3

[0105] In the formation of the protection film, a probe was produced in the same manner as in Example 1, except for changing polymers for a protection film.

[0106] More specifically, the probe produced in Example 1 was immersed 6 times at 10 minutes intervals in a solution in which 300 mg of poly(styrene-ran-4-vinylpyridine-ran-propyleneglycol methacrylate) (M.sub.w/M.sub.n=1.8, m=2) [copolymer (4)] represented by Formula (4), 300 mg of poly(styrene-ran-4-vinylpyridine-ran-propyleneglycol methacrylate) (M.sub.w/M.sub.n=1.6; m=about 16) [copolymer (5)] represented by Formula (5), and 47 mg of polyethylene glycol diglycidyl ether (PEGDGE) (Mn=1000) as a crosslinking agent were dissolved in 1 mL of a solvent. Thereafter, the probe was dried over 48 hours at room temperature to form a crosslinked protection film, and thereby a probe C was obtained. The formation conditions of the above-described protection film were summarized in Table 1.

[0107] <Measurement of Probe Characteristics>

[0108] [Glucose Response Characteristics]

[0109] The glucose response characteristics of the probe C was measured in the same manner as in Example 1.

[0110] High linearity was shown at a glucose concentration of 0 to 500 mg/dL, and glucose response was favorable. The result is shown in FIG. 11 and summarized in Table 2.

[0111] [Durability]

[0112] The durability of the probe C was measured in the same manner as in Example 1.

[0113] Response characteristics 7 days after storage showed high linearity at a glucose concentration of 0 to 500 mg/dL and showed almost no change compared to day 0, and durability was favorable. The result is shown in FIG. 12 and summarized in Table 2.

Example 4

[0114] <Production of Probe>

[0115] In the formation of the protection film, a probe was produced in the same manner as in Example 1, except for changing polymers for a protection film.

[0116] More specifically, the probe produced as described above was immersed 8 times at 10 minutes intervals in a solution in which 300 mg of poly(styrene-ran-4-vinylpyridine-ran-propyleneglycol methacrylate) (M.sub.w/M.sub.n=1.8, m=2) [random copolymer (4)] represented by Formula (4), 300 mg of poly(4-vinylpyridine)-block-poly(2,2-dimethylethyl methacrylate) (M.sub.w/M.sub.n=1.15; w=77.0g80.010.sup.3) [block copolymer (6)] represented by Formula (6),

##STR00006##

and 47 mg of polyethylene glycol diglycidyl ether (PEGDGE) (Mn=1000) as a crosslinking agent were dissolved in 1 mL of a solvent (ethanol 95%, 4-(2-hydroxyethyl)-1-piperazine ethanesulfonic acid (HEPES) buffer solution (10 mM, pH 8) 5%). Thereafter, the probe was dried over 48 hours at room temperature to form a crosslinked protection film, and thereby a probe D was obtained. The formation conditions of the above-described protection film were summarized in Table 3.

[0117] <Measurement of Probe Characteristics>

[0118] [Glucose Response Characteristics]

[0119] The glucose response characteristics of the probe D was measured in the same manner as in Example 1.

[0120] High linearity was shown at a glucose concentration of 0 to 500 mg/dL, and glucose response was favorable. The result is shown in FIG. 13 and summarized in Table 4.

[0121] [Durability]

[0122] The durability of the probe D was measured in the same manner as in Example 1.

[0123] Response characteristics 7 days after storage showed high linearity at a glucose concentration of 0 to 500 mg/dL and showed almost no change compared to day 0, and durability was favorable. The result is shown in FIG. 14 and summarized in Table 4.

Example 5

[0124] <Production of Probe>

[0125] In the formation of the protection film, a probe was produced in the same manner as in Example 4, except for changing polymers for a protection film.

[0126] More specifically, a protection film was formed in the same manner as in Example 4 except for using poly(4-vinylpyridine)-block-poly(n-butyl methacrylate) (M.sub.w/M.sub.n=1.3; w=6.0g4.510.sup.3) [block copolymer (7)] represented by Formula (7):

##STR00007##

[0127] in place of poly(4-vinylpyridine)-block-poly(2,2-dimethylethyl methacrylate) [block copolymer (6)] represented by Formula (6) in Example 4, and thus a probe E was obtained. The formation conditions of the above-described protection film were summarized in Table 3.

[0128] <Measurement of Probe Characteristics>

[0129] [Glucose Response Characteristics]

[0130] The glucose response characteristics of the probe E was measured in the same manner as in Example 1.

[0131] High linearity was shown at a glucose concentration of 0 to 500 mg/dL, and glucose response was favorable. The result is shown in FIG. 13 and summarized in Table 4.

[0132] [Durability]

[0133] The durability of the probe E was measured in the same manner as in Example 1.

[0134] Response characteristics 7 days after storage showed high linearity at a glucose concentration of 0 to 500 mg/dL and showed almost no change compared to day 0, and durability was favorable. The result is shown in FIG. 14 and summarized in Table 4.

Example 6

[0135] In the formation of the protection film, a probe was produced in the same manner as in Example 4, except for changing polymers for a protection film.

[0136] More specifically, a protection film was formed in the same manner as in Example 4 except for using poly(4-vinylpyridine-ran-2-hydroxyethyl methacrylate) (M.sub.w/M.sub.n=1.2) [random copolymer (8)] represented by Formula (8):

##STR00008##

[0137] in place of poly(4-vinylpyridine)-block-poly(2,2-dimethylethyl methacrylate) [block copolymer (6)] represented by Formula (6) in Example 4, and thus a probe F was obtained. The formation conditions of the above-described protection film were summarized in Table 3.

[0138] <Measurement of Probe Characteristics>

[0139] [Glucose Response Characteristics]

[0140] The glucose response characteristics of the probe F was measured in the same manner as in Example 1.

[0141] High linearity was shown at a glucose concentration of 0 to 500 mg/dL, and glucose response was favorable. The result is shown in FIG. 13 and summarized in Table 4.

[0142] [Durability]

[0143] The durability of the probe F was measured in the same manner as in Example 1.

[0144] Response characteristics 7 days after storage showed high linearity at a glucose concentration of 0 to 500 mg/dL and showed almost no change compared to day 0, and durability was favorable. The result is shown in FIG. 14 and summarized in Table 4.

Example 7

[0145] In the formation of the protection film, a probe was produced in the same manner as in Example 4, except for changing polymers for a protection film.

[0146] More specifically, a protection film was formed in the same manner as in Example 4 except for using poly(4-vinylpyridine-ran-2-hydroxyethyl methacrylate) (M.sub.w/M.sub.n=1.6) [random copolymer (9)] represented by Formula (9):

##STR00009##

[0147] in place of poly(4-vinylpyridine)-block-poly(2,2-dimethylethyl methacrylate) [block copolymer (6)] represented by Formula (6) in Example 4, and thus a probe G was obtained. The formation conditions of the above-described protection film were summarized in Table 3.

[0148] <Measurement of Probe Characteristics>

[0149] [Glucose Response Characteristics]

[0150] The glucose response characteristics of the probe G was measured in the same manner as in Example 1.

[0151] High linearity was shown at a glucose concentration of 0 to 500 mg/dL, and glucose response was favorable. The result is shown in FIG. 13 and summarized in Table 4.

[0152] [Durability]

[0153] The durability of the probe G was measured in the same manner as in Example 1.

[0154] Response characteristics 7 days after storage showed high linearity at a glucose concentration of 0 to 500 mg/dL and showed almost no change compared to day 0, and durability was favorable. The result is shown in FIG. 14 and summarized in Table 4.

Example 8

[0155] In the formation of the protection film, a probe was produced in the same manner as in Example 1, except for changing polymers for a protection film.

[0156] More specifically, the probe produced as described above was immersed 8 times at 10 minutes intervals in a solution in which 300 mg of poly(styrene-ran-4-vinylpyridine-ran-propyleneglycol methacrylate) (M.sub.w/M.sub.n=1.6, m=about 16) [random copolymer (5)] represented by Formula (5), 300 mg of poly(4-vinylpyridine)-block-poly(2,2-dimethylethyl methacrylate) (M.sub.w/M.sub.n=1.15; w=77.0g80.010.sup.3) [block copolymer (6)] represented by Formula (6), and 47 mg of polyethylene glycol diglycidyl ether (PEGDGE) (Mn=1000) as a crosslinking agent were dissolved in 1 mL of a solvent (ethanol 95%, 4-(2-hydroxyethyl)-1-piperazine ethanesulfonic acid (HEPES) buffer solution (10 mM, pH 8) 5%). Thereafter, the probe was dried over 48 hours at room temperature to form a crosslinked protection film, and thereby a probe H was obtained. The formation conditions of the above-described protection film were summarized in Table 5.

[0157] <Measurement of Probe Characteristics>

[0158] [Glucose Response Characteristics]

[0159] The glucose response characteristics of the probe H was measured in the same manner as in Example 1.

[0160] High linearity was shown at a glucose concentration of 0 to 500 mg/dL, and glucose response was favorable. The result is shown in FIG. 15 and summarized in Table 6.

[0161] [Durability]

[0162] The durability of the probe H was measured in the same manner as in Example 1.

[0163] Response characteristics 7 days after storage showed high linearity at a glucose concentration of 0 to 500 mg/dL and showed almost no change compared to day 0, and durability was favorable. The result is shown in FIG. 16 and summarized in Table 6.

Example 9

[0164] In the formation of the protection film, a probe was produced in the same manner as in Example 8, except for changing polymers for a protection film.

[0165] More specifically, a protection film was formed in the same manner as in Example 8 except for using poly(4-vinylpyridine)-block-poly(n-butyl methacrylate) (M.sub.w/M.sub.n=1.3; w=6.0g4.510.sup.3) [block copolymer (7)] represented by Formula (7) in place of poly(4-vinylpyridine)-block-poly(2,2-dimethylethyl methacrylate) [block copolymer (6)] represented by Formula (6) in Example 8, and thus a probe I was obtained. The formation conditions of the above-described protection film were summarized in Table 5.

[0166] <Measurement of Probe Characteristics>

[0167] [Glucose Response Characteristics]

[0168] The glucose response characteristics of the probe I was measured in the same manner as in Example 1.

[0169] High linearity was shown at a glucose concentration of 0 to 500 mg/dL, and glucose response was favorable. The result is shown in FIG. 15 and summarized in Table 6.

[0170] [Durability]

[0171] The durability of the probe I was measured in the same manner as in Example 1.

[0172] Response characteristics 7 days after storage maintained linearity at a glucose concentration of 0 to 500 mg/dL, and durability was favorable. The result is shown in FIG. 16 and summarized in Table 6.

Example 10

[0173] In the formation of the protection film, a probe was produced in the same manner as in Example 8, except for changing polymers for a protection film.

[0174] More specifically, a protection film was formed in the same manner as in Example 8 except for using poly(4-vinylpyridine-ran-2-hydroxyethyl methacrylate) [random copolymer (9)] represented by Formula (9) in place of poly(4-vinylpyridine)-block-poly(2,2-dimethylethyl methacrylate) [block copolymer (6)] represented by Formula (6) in Example 8, and thus a probe J was obtained. The formation conditions of the above-described protection film were summarized in Table 5.

[0175] <Measurement of Probe Characteristics>

[0176] [Glucose Response Characteristics]

[0177] The glucose response characteristics of the probe J was measured in the same manner as in Example 1.

[0178] High linearity was shown at a glucose concentration of 0 to 500 mg/dL, and glucose response was favorable. The result is shown in FIG. 15 and summarized in Table 6.

[0179] [Durability]

[0180] The durability of the probe K was measured in the same manner as in Example 1.

[0181] Response characteristics 7 days after storage maintained linearity at a glucose concentration of 0 to 500 mg/dL, and durability was favorable. The result is shown in FIG. 16 and summarized in Table 6.

Comparative Example 1

[0182] In the formation of the protection film, a probe was produced in the same manner as in Example 1, except for changing polymers for a protection film and increasing the number of immersions in the crosslinking agent solution.

[0183] More specifically, the probe produced as described above was immersed 9 times at 10 minutes intervals in a solution in which 300 mg of poly(styrene-ran-4-vinylpyridine-ran-propyleneglycol methacrylate) (M.sub.w/M.sub.n=1.8, m=2) [random copolymer (4)] represented by Formula (4), 300 mg of poly(4-vinylpyridine) (M.sub.w=160,000) [P4VP], and 47 mg of polyethylene glycol diglycidyl ether (PEGDGE) (Mn=1000) as a crosslinking agent were dissolved in 1 mL of a solvent (ethanol 95%, 4-(2-hydroxyethyl)-1-piperazine ethanesulfonic acid (HEPES) buffer solution (10 mM, pH 8) 5%). Thereafter, the probe was dried over 48 hours at room temperature to form a crosslinked protection film, and thereby a probe K was obtained. The formation conditions of the above-described protection film were summarized in Table 7.

[0184] <Measurement of Probe Characteristics>

[0185] [Glucose Response Characteristics]

[0186] The glucose response characteristics of the probe K was measured in the same manner as in Example 1.

[0187] High linearity was shown at a glucose concentration of 0 to 500 mg/dL, and glucose response was favorable. The result is shown in FIG. 17 and summarized in Table 8.

[0188] [Durability]

[0189] The durability of the probe K was measured in the same manner as in Example 1.

[0190] Response characteristics 7 days after storage decreased to 48% at a glucose concentration of greater than 100 mg/dL, and durability was poor. The result is shown in FIG. 18 and summarized in Table 8.

Comparative Example 2

[0191] In the formation of the protection film, a probe was produced in the same manner as in Example 1, except for changing polymers for a protection film and increasing the number of immersions in the crosslinking agent solution.

[0192] More specifically, the probe produced as described above was immersed 9 times at 10 minutes intervals in a solution in which 300 mg of poly(styrene-ran-4-vinylpyridine-ran-propyleneglycol methacrylate) (M.sub.w/M.sub.n=1.6, m=about 16) [random copolymer (5)] represented by Formula (5), 300 mg of poly(4-vinylpyridine) (M.sub.w=160,000) [P4VP], and 47 mg of polyethylene glycol diglycidyl ether (PEGDGE) (Mn=1000) as a crosslinking agent were dissolved in 1 mL of a solvent (ethanol 95%, 4-(2-hydroxyethyl)-1-piperazine ethanesulfonic acid (HEPES) buffer solution (10 mM, pH 8) 5%). Thereafter, the probe was dried over 48 hours at room temperature to form a crosslinked protection film, and thereby a probe L was obtained. The formation conditions of the above-described protection film were summarized in Table 7.

[0193] <Measurement of Probe Characteristics>

[0194] [Glucose Response Characteristics]

[0195] The glucose response characteristics of the probe L was measured in the same manner as in Example 1.

[0196] High linearity was shown at a glucose concentration of 0 to 500 mg/dL, and glucose response was favorable. The result is shown in FIG. 17 and summarized in Table 8.

[0197] [Durability]

[0198] The durability of the probe L was measured in the same manner as in Example 1.

[0199] Response characteristics 7 days after storage decreased to 36% at a glucose concentration of greater than 100 mg/dL, and durability was poor. The result is shown in FIG. 18 and summarized in Table 8.

Comparative Example 3

[0200] In the formation of the protection film, a probe was produced in the same manner as in Example 1, except for changing polymers for a protection film, increasing an amount of the crosslinking agent, and increasing the number of immersions in the crosslinking agent solution.

[0201] More specifically, the probe produced as described above was immersed 9 times at 10 minutes intervals in a solution in which 800 mg of poly(4-vinylpyridine) (M.sub.w=160,000) [P4VP] and 62 mg of polyethylene glycol diglycidyl ether (PEGDGE) (Mn=1000) as a crosslinking agent were dissolved in 1 mL of a solvent (ethanol 95%, 4-(2-hydroxyethyl)-1-piperazine ethanesulfonic acid (HEPES) buffer solution (10 mM, pH 8) 5%). Thereafter, the probe was dried over 48 hours at room temperature to form a crosslinked protection film, and thereby a probe M was obtained. Formation conditions of the above-described protection film were summarized in Table 7.

[0202] <Measurement of Probe Characteristics>

[0203] [Glucose Response Characteristics]

[0204] The glucose response characteristics of the probe M was measured in the same manner as in Example 1.

[0205] High linearity was shown at a glucose concentration of 0 to 500 mg/dL, and glucose response was favorable. The result is shown in FIG. 17 and summarized in Table 8.

[0206] [Durability]

[0207] The durability of the probe M was measured in the same manner as in Example 1.

[0208] Response characteristics 7 days after storage decreased to 22% at a glucose concentration of greater than 100 mg/dL, and durability was poor. The result is shown in FIG. 18 and summarized in Table 8.

Reference Example 1

[0209] In the formation of the protection film, a probe was produced in the same manner as in Example 1, except for changing polymers for a protection film, increasing the amount of the crosslinking agent, and increasing the number of immersions in the crosslinking agent solution.

[0210] More specifically, the probe produced as described above was immersed 12 times at 10 minutes intervals in a solution in which 800 mg of poly(4-vinylpyridine)-block-poly(n-butyl methacrylate) (M.sub.w/M.sub.n=1.3; w=6.0g4.510.sup.3) [block copolymer (7)] represented by Formula (7), and 62 mg of polyethylene glycol diglycidyl ether (PEGDGE) (Mn=1000) as a crosslinking agent were dissolved in 1 mL of a solvent (ethanol 95%, 4-(2-hydroxyethyl)-1-piperazine ethanesulfonic acid (HEPES) buffer solution (10 mM, pH 8) 5%). Thereafter, the probe was dried over 48 hours at room temperature to form a crosslinked protection film, and thereby a probe N was obtained. The formation conditions of the above-described protection film were summarized in Table 9.

[0211] <Measurement of Probe Characteristics>

[0212] [Glucose Response Characteristics]

[0213] The glucose response characteristics of the probe N was measured in the same manner as in Example 1.

[0214] High linearity was shown at a glucose concentration of 0 to 500 mg/dL, and glucose response was favorable. The result is shown in FIG. 19 and summarized in Table 10.

[0215] [Durability]

[0216] The durability of the probe N was measured in the same manner as in Example 1.

[0217] Response characteristics 7 days after storage decreased to 46% at a glucose concentration of greater than 200 mg/dL, and durability was poor. The result is shown in FIG. 20 and summarized in Table 10.

Reference Example 2

[0218] In the formation of the protection film, a probe was produced in the same manner as in Example 1, except for changing polymers for a protection film and increasing the amount of the crosslinking agent.

[0219] More specifically, the probe produced as described above was immersed 8 times at 10 minutes intervals in a solution in which 800 mg of poly(4-vinylpyridine-ran-2-hydroxyethyl methacrylate) [random copolymer (8)] represented by Formula (8) and 62 mg of polyethylene glycol diglycidyl ether (PEGDGE) (Mn=1000) as a crosslinking agent were dissolved in 1 mL of a solvent (ethanol 95%, 4-(2-hydroxyethyl)-1-piperazine ethanesulfonic acid (HEPES) buffer solution (10 mM, pH 8) 5%). Thereafter, the probe was dried over 48 hours at room temperature to form a crosslinked protection film, and thereby a probe O was obtained. The formation conditions of the above-described protection film were summarized in Table 9.

[0220] <Measurement of Probe Characteristics>

[0221] [Glucose Response Characteristics]

[0222] The glucose response characteristics of the probe O was measured in the same manner as in Example 1.

[0223] High linearity was shown at a glucose concentration of 0 to 500 mg/dL, and glucose response was favorable. The result is shown in FIG. 19 and summarized in Table 10.

[0224] [Durability]

[0225] The durability of the probe O was measured in the same manner as in Example 1.

[0226] Response characteristics 7 days after storage decreased to 25% at a glucose concentration of greater than 200 mg/dL, and durability was poor. The result is shown in FIG. 20 and summarized in Table 10.

Reference Example 3

[0227] In the formation of the protection film, a probe was produced in the same manner as in Example 1, except for changing polymers for a protection film and increasing the amount of the crosslinking agent.

[0228] More specifically, the probe produced as described above was immersed 8 times at 10 minutes intervals in a solution in which 800 mg of poly(4-vinylpyridine-ran-2-hydroxyethyl methacrylate) [random copolymer (9)] represented by Formula (9) and 62 mg of polyethylene glycol diglycidyl ether (PEGDGE) (Mn=1000) as a crosslinking agent were dissolved in 1 mL of a solvent (ethanol 95%, 4-(2-hydroxyethyl)-1-piperazine ethanesulfonic acid (HEPES) buffer solution (10 mM, pH 8) 5%). Thereafter, the probe was dried over 48 hours at room temperature to form a crosslinked protection film, and thereby a probe P was obtained. The formation conditions of the above-described protection film were summarized in Table 9.

[0229] <Measurement of Probe Characteristics>

[0230] [Glucose Response Characteristics]

[0231] The glucose response characteristics of the probe P was measured in the same manner as in Example 1.

[0232] High linearity was shown at a glucose concentration of 0 to 500 mg/dL, and glucose response was favorable. The result is shown in FIG. 19 and summarized in Table 10.

[0233] [Durability]

[0234] The durability of the probe P was measured in the same manner as in Example 1.

[0235] Response characteristics 7 days after storage decreased to 32% at a glucose concentration of greater than 200 mg/dL, and durability was poor. The result is shown in FIG. 20 and summarized in Table 10.

Reference Example 4

[0236] In the formation of the protection film, a probe was produced in the same manner as in Example 1, except for changing polymers for a protection film and increasing the amount of the crosslinking agent.

[0237] More specifically, the probe produced as described above was immersed 8 times at 10 minutes intervals in a solution in which 400 mg of poly(4-vinylpyridine-ran-2-hydroxyethyl methacrylate) [random copolymer (8)] represented by Formula (8), 400 mg of poly(4-vinylpyridine-ran-2-hydroxyethyl methacrylate) [random copolymer (9)] represented by Formula (9), and 62 mg of polyethylene glycol diglycidyl ether (PEGDGE) (Mn=1000) as a crosslinking agent were dissolved in 1 mL of a solvent (ethanol 95%, 4-(2-hydroxyethyl)-1-piperazine ethanesulfonic acid (HEPES) buffer solution (10 mM, pH 8) 5%). Thereafter, the probe was dried over 48 hours at room temperature to form a crosslinked protection film, and thereby a probe Q was obtained. The formation conditions of the above-described protection film were summarized in Table 9.

[0238] <Measurement of Probe Characteristics>

[0239] [Glucose Response Characteristics]

[0240] The glucose response characteristics of the probe Q was measured in the same manner as in Example 1.

[0241] High linearity was shown at a glucose concentration of 0 to 500 mg/dL, and glucose response was favorable. The result is shown in FIG. 19 and summarized in Table 10.

[0242] [Durability]

[0243] The durability of the probe Q was measured in the same manner as in Example 1.

[0244] Response characteristics 7 days after storage decreased to 30% at a glucose concentration of greater than 200 mg/dL, and durability was poor. The result is shown in FIG. 20 and summarized in Table 10.

TABLE-US-00001 TABLE 1 Probe A Probe B Probe C (w/v) (w/v) (w/v) Copolymer (4) 6% 3% Copolymer (5) 6% 3% Copolymer (6) Copolymer (7) Copolymer (8) Copolymer (9) P4VP PEGDGE 0.47% 0.47% 0.47% No. of Dips 6 6 6

TABLE-US-00002 TABLE 2 Glucose Probe A Probe B Probe C Addition Day Day Day Day Day Day (mg/dL) 0 7 0 7 0 7 0 0 0 0 0 0 0 50 10 9 10 14 12 10 100 20 19 22 30 24 16 200 40 37 42 55 46 38 300 61 53 63 75 65 57 400 80 72 81 89 83 76 500 100 85 100 104 100 90

TABLE-US-00003 TABLE 3 Probe D Probe E Probe F Probe G (w/v) (w/v) (w/v) (w/v) Copolymer (4) 3% 3% 3% 3% Copolymer (5) Copolymer (6) 3% Copolymer (7) 3% Copolymer (8) 3% Copolymer (9) 3% P4VP PEGDGE 0.47% 0.47% 0.47% 0.47% No. of Dips 8 8 8 8

TABLE-US-00004 TABLE 4 Glucose Probe D Probe E Probe F Probe G Addition Day Day Day Day Day Day Day Day (mg/dL) 0 7 0 7 0 7 0 7 0 0 0 0 0 0 0 0 0 50 3 5 11 7 9 4 10 8 100 15 12 21 15 21 11 23 17 200 34 25 43 28 40 23 43 31 300 56 39 63 42 61 34 64 48 400 79 51 83 51 82 45 83 61 500 100 77 100 60 100 55 100 71

TABLE-US-00005 TABLE 5 Probe H Probe I Probe J (w/v) (w/v) (w/v) Copolymer (4) Copolymer (5) 3% 3% 3% Copolymer (6) 3% Copolymer (7) 3% Copolymer (8) Copolymer (9) 3% P4VP PEGDGE 0.47% 0.47% 0.47% No. of Dips 8 8 8

TABLE-US-00006 TABLE 6 Glucose Probe H Probe I Probe J Addition Day Day Day Day Day Day (mg/dL) 0 7 0 7 0 7 0 0 0 0 0 0 0 50 8 7 8 8 13 9 100 19 14 22 16 25 18 200 38 26 42 30 48 32 300 59 40 62 42 68 43 400 78 51 81 51 85 52 500 100 63 100 60 100 56

TABLE-US-00007 TABLE 7 Probe K Probe L Probe M (w/v) (w/v) (w/v) Copolymer (4) 3% Copolymer (5) 3% Copolymer (6) Copolymer (7) Copolymer (8) Copolymer (9) P4VP 3% 3% 8% PEGDGE 0.47% 0.47% 0.62% No. of Dips 9 9 9

TABLE-US-00008 TABLE 8 Glucose Probe K Probe L Probe M Addition Day Day Day Day Day Day (mg/dL) 0 7 0 7 0 7 0 0 0 0 0 0 0 50 11 7 10 4 10 8 100 23 14 19 9 18 14 200 44 25 37 17 38 21 300 63 34 55 25 57 23 400 81 41 75 31 78 23 500 100 48 100 36 100 22

TABLE-US-00009 TABLE 9 Probe N Probe O Probe P Probe Q (w/v) (w/v) (w/v) (w/v) Copolymer (4) Copolymer (5) Copolymer (6) Copolymer (7) 8% Copolymer (8) 8% 4% Copolymer (9) 8% 4% P4VP PEGDGE 0.62% 0.62% 0.62% 0.62% No. of Dips 12 8 8 8

TABLE-US-00010 TABLE 10 Glucose Probe N Probe O Probe P Probe Q Addition Day Day Day Day Day Day Day Day (mg/dL) 0 7 0 7 0 7 0 7 0 0 0 0 0 0 0 0 0 50 12 12 11 7 14 11 10 10 100 22 22 21 13 26 18 19 18 200 43 37 39 22 46 28 37 28 300 62 45 55 24 62 32 54 31 400 81 46 74 24 78 33 73 31 500 100 46 100 25 100 32 100 30

[0245] It was confirmed that using a protection film including the polymer mixture of the present disclosure for a sensing part of a probe yielded favorable glucose response and enhanced durability compared to the conventional polymers.

INDUSTRIAL APPLICABILITY

[0246] The film structure of the present disclosure, including a detection layer including at least an analyte-responsive enzyme and a redox mediator, and a protection film formed on the detection layer, is useful for a probe of an embedded-type biosensor.

REFERENCE SIGNS LIST

[0247] 1 Embedded-type biosensor [0248] 10 Main body [0249] 11 Probe [0250] 111 Insulating substrate [0251] 112 Conductive thin film [0252] 112a Working electrode lead [0253] 112b Reference electrode lead [0254] 112c Counter electrode lead [0255] 113 Groove [0256] 114 Working electrode [0257] 115 Reference electrode [0258] 116 Insulating resist [0259] 117 Counter electrode [0260] 118 Detection layer [0261] 119 Protection film [0262] 2 Living body [0263] 3 Information communication device