A blood sugar test strip and preparation method thereof

Abstract

The invention provides a blood glucose test paper and a preparation method thereof, and belongs to the technical field of test paper. 3,3',5,5'-tetramethylbenzidine is dissolved in ethanol, a catalytic color development factor is added, ultrasonic dispersion is uniform, sprayed on a PET film through a spraying device, freeze-dried, coated with a PET film, and a blood contact hole and an observation hole are reserved to obtain a blood glucose test paper. The preparation method of the blood glucose test paper prepared by the invention is simple, easy to operate, low in cost, a low concentration of catalytic color development factor can efficiently complete the catalytic reaction, the reaction sensitivity is high, the result is accurate, the detection limit is low, and it has broad application prospects.

Description

Technical Field

[0001] The invention relates to the technical field of test strips, and in particular to a blood sugar test strip and a preparation method thereof. Background Art

[0002] Diabetes is one of the major diseases that endanger human health. Its symptoms are mainly manifested by abnormal glucose levels in blood and urine. Studies have found that if blood is measured regularly using a blood sugar measuring device, blood sugar can be well controlled, thereby well controlling various complications of diabetes.

[0003] The blood sugar concentration in human blood is measured before and after meals to check whether the diet control is qualified, so as to adjust the diet and living habits and provide reference values ​​for the treatment of diabetes.

[0004] Existing blood glucose test strips are difficult to manufacture and are expensive. Consumers will consume a large number of blood glucose test strips when measuring their blood glucose frequently, which increases the financial burden on patients. Therefore, it is of great significance to develop simple-to-use and low-cost blood glucose test strips. Summary of the invention

[0005] The purpose of the present invention is to provide a blood glucose test strip and a preparation method thereof. The preparation method is simple, easy to operate, and low in cost. A low concentration of catalytic color developing factor can efficiently complete the catalytic reaction, the reaction sensitivity is high, the result is accurate, the detection limit is low, and the test strip has broad application prospects.

[0006] The technical solution of the present invention is achieved in this way:

[0007] The invention provides a method for preparing a blood glucose test strip, comprising the following steps: dissolving 3,3',5,5'-tetramethylbenzenediamine in ethanol, adding a catalytic color development factor, uniformly dispersing by ultrasonication, spraying the mixture onto a PET film by a spraying device, freeze drying, coating the mixture with the PET film, and leaving a blood contact hole and an observation hole to obtain the blood glucose test strip.

[0008] As a further improvement of the present invention, the mass ratio of the 3,3',5,5'-tetramethylbenzenediamine to the catalytic color development factor is 2-4:9-12.

[0009] As a further improvement of the present invention, the spraying pressure is 2-3 bar, the spraying time is 5-15 seconds, and the spraying volume is 3-5 mL / cm 2 .

[0010] As a further improvement of the present invention, the preparation method of the catalytic color developing factor is as follows:

[0011] S1. Preparation of mesoporous silica nanospheres: dissolving alkyl orthosilicate in ethanol, adding porogen, ammonia and water, stirring for reaction, centrifuging, washing, drying and calcining to obtain mesoporous silica nanospheres;

[0012] S2. Preparation of Cu / Ce-doped magnetic mesoporous silica nanospheres: dissolving cupric chloride, cerium chloride, ferric chloride and ferrous chloride in water, adding mesoporous silica nanospheres, adding ammonia water dropwise under inert gas protection, heating and stirring to react, centrifuging, washing, drying and calcining to obtain Cu / Ce-doped magnetic mesoporous silica nanospheres;

[0013] S3. Loading of graphene oxide: adding Cu / Ce-doped magnetic mesoporous silica nanospheres to an aqueous dispersion of graphene oxide, stirring and mixing, and spray drying to obtain graphene oxide-loaded Cu / Ce-doped magnetic mesoporous silica nanospheres;

[0014] S4. Tannic acid modification: adding graphene oxide loaded Cu / Ce doped magnetic mesoporous silica nanospheres to water, adding tannic acid and a catalyst, heating and stirring to react, separating with a magnet, washing, and drying to obtain modified graphene oxide loaded Cu / Ce doped magnetic mesoporous silica nanospheres;

[0015] S5. Immobilization of glucose oxidase: Add modified graphene oxide loaded Cu / Ce-doped magnetic mesoporous silica nanospheres into water, add NHS and EDC, stir to activate, add glucose oxidase, stir to react, separate with a magnet, wash, freeze-dry, and obtain a catalytic color developing factor.

[0016] As a further improvement of the present invention, the alkyl orthosilicate in step S1 is methyl orthosilicate or ethyl orthosilicate, the porogen is hexadecyltrimethylammonium chloride or hexadecyltrimethylammonium bromide, the mass ratio of the alkyl orthosilicate, ethanol, porogen, ammonia water and water is 10-12:70-100:1-2:4-6:5-7, the stirring reaction time is 10-12h, the calcination temperature is 400-500°C, and the time is 2-4h.

[0017] As a further improvement of the present invention, the mass ratio of cupric chloride, cerium chloride, ferric chloride, ferrous chloride, mesoporous silica nanospheres and ammonia water in step S2 is 0.3-0.5:0.1-0.3:3.24:1.26:10:5-7, the temperature of the heating and stirring reaction is 80-90°C, the time is 3-5h, and the calcination temperature is 350-450°C, and the time is 1-3h.

[0018] As a further improvement of the present invention, the concentration of the graphene oxide aqueous dispersion in step S3 is 0.5-1.5 mg / mL, and the solid-to-liquid ratio of the Cu / Ce-doped magnetic mesoporous silica nanospheres and the graphene oxide aqueous dispersion is 1:3-5 g / mL.

[0019] As a further improvement of the present invention, in step S4, the mass ratio of the graphene oxide-loaded Cu / Ce-doped magnetic mesoporous silica nanospheres, tannic acid and catalyst is 10:3-4:0.5-1, the catalyst is a Tris-HCl solution with a pH of 8.5-9.5, the temperature of the heating and stirring reaction is 50-60°C, and the time is 2-4h.

[0020] As a further improvement of the present invention, in step S5, the mass ratio of the modified graphene oxide loaded Cu / Ce-doped magnetic mesoporous silica nanospheres, NHS, EDC and glucose oxidase is 10:3-4:2-3:3-5, the stirring activation time is 20-40 min, and the stirring reaction time is 7-10 h.

[0021] The present invention further protects a blood glucose test paper prepared by the above preparation method.

[0022] The present invention has the following beneficial effects:

[0023] The invention prepares a catalytic color developing factor, which has a carrier of mesoporous silica nanospheres, magnetic ferrosoferric oxide deposited on the surface, and is doped with copper oxide and cerium oxide, and has high-efficiency peroxidase activity. Meanwhile, the magnetic ferrosoferric oxide also facilitates the separation step of the catalytic color developing factor in the preparation process, so that the preparation is simpler and the operation is more convenient. The doping of copper oxide and cerium oxide greatly improves the catalytic activity to hydrogen peroxide, so that the reaction color development of the hydrogen peroxide with 3,3',5,5'-tetramethylbenzenediamine is more sensitive. The surface is loaded with graphene oxide, and due to its rapid electron transfer and substrate adsorption ability, the catalytic activity of the peroxidase is further improved, so that the concentration of hydrogen peroxide can be obviously and accurately obtained. The prepared product has peroxidase-like activity. After the surface is modified with tannic acid, it is coupled with glucose oxidase through activation energy, thereby fixing the glucose oxidase, allowing glucose to undergo an oxidation reaction in situ to generate hydrogen peroxide, so that the concentration of glucose in the blood can be indirectly obtained by detecting the concentration of hydrogen peroxide. The catalytic color factor has a large specific surface area and a large pore volume, and can repeat complex enzymes and catalytic factors, thereby making the reaction more sensitive and the detection more accurate, simple and convenient.

[0024] In the present invention, the immobilized glucose oxidase utilizes oxygen to convert glucose into gluconic acid while releasing hydrogen peroxide.

[0025] Glucose + H2O + O2 → Gluconic acid + H2O2

[0026] The copper oxide and cerium oxide in the catalytic color developing factors are doped with ferrous oxide and graphene oxide as simulated peroxidase, catalyzing the reaction of hydrogen peroxide with 3,3',5,5'-tetramethylbenzidine. Since the concentration of decomposed glucose is proportional to the concentration of generated hydrogen peroxide during the decomposition of glucose, the glucose concentration can be indirectly measured by measuring the concentration of hydrogen peroxide.

[0027] The preparation method of the blood glucose test paper prepared by the invention is simple, easy to operate, and low in cost; a low concentration of catalytic color developing factor can efficiently complete the catalytic reaction; the reaction sensitivity is high, the result is accurate, the detection limit is low, and the invention has broad application prospects. DETAILED DESCRIPTION

[0028] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0029] NHS, N-hydroxysuccinimide, commercially available.

[0030] EDC, 1-ethyl-(3-dimethylaminopropyl)carbodiimide, is commercially available.

[0031] Glucose oxidase, 10,000 U / g, was purchased from Hebei Jiuyu Biotechnology Co., Ltd.

[0032] Graphene oxide is homemade or commercially available.

[0033] Improved Hummers method for preparing graphene oxide:

[0034] Step 1: weigh 10 g of natural graphite powder, 4 g of potassium persulfate, and 10 g of phosphorus pentoxide, add them into a three-necked flask containing 25 mL of sulfuric acid while stirring, first react in a constant temperature water bath at 60 ° C for 5 h, then move the three-necked flask into a constant temperature water bath and stir at room temperature for 5 h, filter, clear water to neutral, and dry to obtain pre-oxidized graphite;

[0035] Step 2: Weigh 1g of pre-oxidized graphite, add it to a three-necked flask with 25mL of sulfuric acid while stirring, put it in an ice-water bath, and after the pre-oxidized graphite is completely dissolved, add 3g of potassium permanganate, react for 2h, then move the three-necked flask to a constant temperature water bath at 35°C to react for 40min, finally add 50mL of deionized water, continue to react at 35°C for 1h, and finally add 30% H2O2 until no more gas is generated and the solution turns bright yellow. Filter while hot and use 5% hydrochloric acid and water to neutralize. After the final precipitate is ultrasonically shaken for 1h, pour it into a culture dish and dry it at 90°C for 24h to obtain graphene oxide.

[0036] Preparation Example 1 Preparation of catalytic color development factor

[0037] The following steps are involved:

[0038] S1. Preparation of mesoporous silica nanospheres: 10 g of methyl orthosilicate was dissolved in 70 g of ethanol, 1 g of hexadecyltrimethylammonium chloride, 4 g of ammonia water and 5 g of water were added, the mixture was stirred for 10 h, centrifuged, washed, dried and calcined at 400 °C for 2 h to obtain mesoporous silica nanospheres;

[0039] S2. Preparation of Cu / Ce-doped magnetic mesoporous silica nanospheres: 0.3 g of copper chloride, 0.1 g of cerium chloride, 3.24 g of ferric chloride, and 1.26 g of ferrous chloride were dissolved in 100 mL of water, and 10 g of mesoporous silica nanospheres were added. Under nitrogen protection, 5 g of ammonia water was added dropwise, and the mixture was heated to 80°C, stirred for reaction for 3 h, centrifuged, washed, dried, and calcined at 350°C for 1 h to obtain Cu / Ce-doped magnetic mesoporous silica nanospheres.

[0040] S3. Graphene oxide loading: 10 g Cu / Ce doped magnetic mesoporous silica nanospheres were added to 30 g 1 mg / mL graphene oxide aqueous dispersion, stirred for 15 min, and spray dried to obtain graphene oxide loaded Cu / Ce doped magnetic mesoporous silica nanospheres;

[0041] S4. Tannic acid modification: 10 g of graphene oxide loaded Cu / Ce doped magnetic mesoporous silica nanospheres were added to 200 mL of water, 3 g of tannic acid and 0.5 g of catalyst were added, heated to 50°C, stirred for reaction for 2 h, separated by magnet, washed, and dried to obtain modified graphene oxide loaded Cu / Ce doped magnetic mesoporous silica nanospheres;

[0042] The catalyst is a Tris-HCl solution with a pH of 8.5;

[0043] S5. Immobilization of glucose oxidase: Add 10 g of modified graphene oxide loaded Cu / Ce-doped magnetic mesoporous silica nanospheres into 200 mL of water, add 3 g of NHS and 2 g of EDC, stir and activate for 20 min, add 3 g of glucose oxidase, stir and react for 7 h, separate with a magnet, wash, and freeze-dry to obtain a catalytic color developing factor.

[0044] Preparation Example 2 Preparation of catalytic color development factor

[0045] The following steps are involved:

[0046] S1. Preparation of mesoporous silica nanospheres: 12 g of tetraethyl orthosilicate was dissolved in 100 g of ethanol, 2 g of hexadecyltrimethylammonium bromide, 6 g of ammonia water and 7 g of water were added, the mixture was stirred for 12 h, centrifuged, washed, dried and calcined at 500 °C for 4 h to obtain mesoporous silica nanospheres;

[0047] S2. Preparation of Cu / Ce-doped magnetic mesoporous silica nanospheres: 0.5 g of copper chloride, 0.3 g of cerium chloride, 3.24 g of ferric chloride, and 1.26 g of ferrous chloride were dissolved in 100 mL of water, 10 g of mesoporous silica nanospheres were added, 7 g of ammonia water was added dropwise under nitrogen protection, heated to 90°C, stirred for 5 h, centrifuged, washed, dried, and calcined at 450°C for 3 h to obtain Cu / Ce-doped magnetic mesoporous silica nanospheres;

[0048] S3. Graphene oxide loading: 10 g Cu / Ce doped magnetic mesoporous silica nanospheres were added to 50 g 1 mg / mL graphene oxide aqueous dispersion, stirred for 15 min, and spray dried to obtain graphene oxide loaded Cu / Ce doped magnetic mesoporous silica nanospheres;

[0049] S4. Tannic acid modification: 10 g of graphene oxide loaded Cu / Ce doped magnetic mesoporous silica nanospheres were added to 200 mL of water, 4 g of tannic acid and 1 g of catalyst were added, heated to 60°C, stirred for reaction for 4 h, separated by magnet, washed, and dried to obtain modified graphene oxide loaded Cu / Ce doped magnetic mesoporous silica nanospheres;

[0050] The catalyst is a Tris-HCl solution with a pH of 9.5;

[0051] S5. Immobilization of glucose oxidase: Add 10 g of modified graphene oxide loaded Cu / Ce-doped magnetic mesoporous silica nanospheres into 200 mL of water, add 4 g of NHS and 3 g of EDC, stir and activate for 40 min, add 5 g of glucose oxidase, stir and react for 10 h, separate with a magnet, wash, and freeze-dry to obtain a catalytic color developing factor.

[0052] Preparation Example 3 Preparation of catalytic color development factor

[0053] The following steps are involved:

[0054] S1. Preparation of mesoporous silica nanospheres: 11 g of tetraethyl orthosilicate was dissolved in 85 g of ethanol, 1.5 g of hexadecyltrimethylammonium bromide, 5 g of ammonia water and 6 g of water were added, the mixture was stirred for 11 h, centrifuged, washed, dried and calcined at 450 ° C for 3 h to obtain mesoporous silica nanospheres;

[0055] S2. Preparation of Cu / Ce-doped magnetic mesoporous silica nanospheres: 0.4 g of copper chloride, 0.2 g of cerium chloride, 3.24 g of ferric chloride, and 1.26 g of ferrous chloride were dissolved in 100 mL of water, 10 g of mesoporous silica nanospheres were added, 6 g of ammonia water was added dropwise under nitrogen protection, the mixture was heated to 85°C, stirred for 4 h, centrifuged, washed, dried, and calcined at 400°C for 2 h to obtain Cu / Ce-doped magnetic mesoporous silica nanospheres;

[0056] S3. Graphene oxide loading: 10 g Cu / Ce doped magnetic mesoporous silica nanospheres were added to 40 g 1 mg / mL graphene oxide aqueous dispersion, stirred for 15 min, and spray dried to obtain graphene oxide loaded Cu / Ce doped magnetic mesoporous silica nanospheres;

[0057] S4. Tannic acid modification: 10 g of graphene oxide loaded Cu / Ce doped magnetic mesoporous silica nanospheres were added to 200 mL of water, 3.5 g of tannic acid and 0.7 g of catalyst were added, heated to 55°C, stirred for reaction for 3 h, separated by magnet, washed, and dried to obtain modified graphene oxide loaded Cu / Ce doped magnetic mesoporous silica nanospheres;

[0058] The catalyst is a Tris-HCl solution with a pH of 9;

[0059] S5. Immobilization of glucose oxidase: Add 10 g of modified graphene oxide loaded Cu / Ce-doped magnetic mesoporous silica nanospheres into 200 mL of water, add 3.5 g of NHS and 2.5 g of EDC, stir and activate for 30 min, add 4 g of glucose oxidase, stir and react for 8 h, separate with a magnet, wash, and freeze-dry to obtain a catalytic color developing factor.

[0060] Comparative Preparation Example 1

[0061] Compared with Preparation Example 3, the difference is that cetyltrimethylammonium bromide is not added in step S1.

[0062] Comparative Preparation Example 2

[0063] Compared with Preparation Example 3, the difference is that copper chloride is not added in step S2.

[0064] The details are as follows:

[0065] S2. Preparation of Ce-doped magnetic mesoporous silica nanospheres: 0.6 g cerium chloride, 3.24 g ferric chloride, and 1.26 g ferrous chloride were dissolved in 100 mL water, and 10 g mesoporous silica nanospheres were added. Under nitrogen protection, 6 g ammonia water was added dropwise, and the mixture was heated to 85 ° C. The mixture was stirred for 4 h, centrifuged, washed, dried, and calcined at 400 ° C for 2 h to obtain Ce-doped magnetic mesoporous silica nanospheres.

[0066] Comparative Preparation Example 3

[0067] Compared with Preparation Example 3, the difference is that cerium chloride is not added in step S2.

[0068] The details are as follows:

[0069] S2. Preparation of Cu-doped magnetic mesoporous silica nanospheres: Dissolve 0.6 g of cupric chloride, 3.24 g of ferric chloride, and 1.26 g of ferrous chloride in 100 mL of water, add 10 g of mesoporous silica nanospheres, and under nitrogen protection, drop 6 g of ammonia water. Heat to 85°C, stir and react for 4 h, centrifuge, wash, dry, and calcine at 400°C for 2 h to obtain Cu-doped magnetic mesoporous silica nanospheres.

[0070] Comparative Preparation Example 4

[0071] Compared with Preparation Example 3, the difference is that copper chloride and cerium chloride are not added in step S2.

[0072] The details are as follows:

[0073] S2. Preparation of magnetic mesoporous silica nanospheres: Dissolve 3.24 g ferric chloride and 1.26 g ferrous chloride in 100 mL water, add 10 g mesoporous silica nanospheres, add 6 g ammonia water dropwise under nitrogen protection, heat to 85°C, stir to react for 4 h, centrifuge, wash, dry, and calcine at 400°C for 2 h to obtain magnetic mesoporous silica nanospheres.

[0074] Comparative Preparation Example 5

[0075] Compared with Preparation Example 3, the difference is that step S2 is not performed.

[0076] The details are as follows:

[0077] S1. Preparation of mesoporous silica nanospheres: 11 g of tetraethyl orthosilicate was dissolved in 85 g of ethanol, 1.5 g of hexadecyltrimethylammonium bromide, 5 g of ammonia water and 6 g of water were added, the mixture was stirred for 11 h, centrifuged, washed, dried and calcined at 450 ° C for 3 h to obtain mesoporous silica nanospheres;

[0078] S2. Graphene oxide loading: 10 g of mesoporous silica nanospheres were added to 40 g of 1 mg / mL graphene oxide aqueous dispersion, stirred for 15 min, and spray dried to obtain graphene oxide loaded mesoporous silica nanospheres;

[0079] S3. Tannic acid modification: 10 g of graphene oxide-supported mesoporous silica nanospheres were added to 200 mL of water, 3.5 g of tannic acid and 0.7 g of catalyst were added, heated to 55°C, stirred for reaction for 3 h, separated by magnet, washed, and dried to obtain modified graphene oxide-supported mesoporous silica nanospheres;

[0080] The catalyst is a Tris-HCl solution with a pH of 9;

[0081] S4. Immobilization of glucose oxidase: Add 10 g of modified graphene oxide-loaded mesoporous silica nanospheres into 200 mL of water, add 3.5 g of NHS and 2.5 g of EDC, stir and activate for 30 min, add 4 g of glucose oxidase, stir and react for 8 h, separate with a magnet, wash, and freeze-dry to obtain a catalytic color developing factor.

[0082] Comparative Preparation Example 6

[0083] Compared with Preparation Example 3, the difference is that step S3 is not performed.

[0084] The details are as follows:

[0085] S1. Preparation of mesoporous silica nanospheres: 11 g of tetraethyl orthosilicate was dissolved in 85 g of ethanol, 1.5 g of hexadecyltrimethylammonium bromide, 5 g of ammonia water and 6 g of water were added, the mixture was stirred for 11 h, centrifuged, washed, dried and calcined at 450 ° C for 3 h to obtain mesoporous silica nanospheres;

[0086] S2. Preparation of Cu / Ce-doped magnetic mesoporous silica nanospheres: 0.4 g of copper chloride, 0.2 g of cerium chloride, 3.24 g of ferric chloride, and 1.26 g of ferrous chloride were dissolved in 100 mL of water, 10 g of mesoporous silica nanospheres were added, 6 g of ammonia water was added dropwise under nitrogen protection, the mixture was heated to 85°C, stirred for 4 h, centrifuged, washed, dried, and calcined at 400°C for 2 h to obtain Cu / Ce-doped magnetic mesoporous silica nanospheres;

[0087] S3. Tannic acid modification: 10 g Cu / Ce-doped magnetic mesoporous silica nanospheres were added to 200 mL water, 3.5 g tannic acid and 0.7 g catalyst were added, heated to 55°C, stirred for 3 h, separated by magnet, washed and dried to obtain modified Cu / Ce-doped magnetic mesoporous silica nanospheres;

[0088] The catalyst is a Tris-HCl solution with a pH of 9;

[0089] S4. Immobilization of glucose oxidase: Add 10 g of modified Cu / Ce-doped magnetic mesoporous silica nanospheres into 200 mL of water, add 3.5 g of NHS and 2.5 g of EDC, stir and activate for 30 min, add 4 g of glucose oxidase, stir and react for 8 h, separate with a magnet, wash, and freeze-dry to obtain a catalytic color developing factor.

[0090] Comparative Preparation Example 7

[0091] Compared with Preparation Example 3, the difference is that step S4 is not performed.

[0092] The details are as follows:

[0093] S1. Preparation of mesoporous silica nanospheres: 11 g of tetraethyl orthosilicate was dissolved in 85 g of ethanol, 1.5 g of hexadecyltrimethylammonium bromide, 5 g of ammonia water and 6 g of water were added, the mixture was stirred for 11 h, centrifuged, washed, dried and calcined at 450 ° C for 3 h to obtain mesoporous silica nanospheres;

[0094] S2. Preparation of Cu / Ce-doped magnetic mesoporous silica nanospheres: 0.4 g of copper chloride, 0.2 g of cerium chloride, 3.24 g of ferric chloride, and 1.26 g of ferrous chloride were dissolved in 100 mL of water, 10 g of mesoporous silica nanospheres were added, 6 g of ammonia water was added dropwise under nitrogen protection, the mixture was heated to 85°C, stirred for 4 h, centrifuged, washed, dried, and calcined at 400°C for 2 h to obtain Cu / Ce-doped magnetic mesoporous silica nanospheres;

[0095] S3. Graphene oxide loading: 10 g Cu / Ce doped magnetic mesoporous silica nanospheres were added to 40 g 1 mg / mL graphene oxide aqueous dispersion, stirred for 15 min, and spray dried to obtain graphene oxide loaded Cu / Ce doped magnetic mesoporous silica nanospheres;

[0096] S4. Immobilization of glucose oxidase: Add 10 g of graphene oxide loaded Cu / Ce doped magnetic mesoporous silica nanospheres into 200 mL of water, add 3.5 g of NHS and 2.5 g of EDC, stir and activate for 30 min, add 4 g of glucose oxidase, stir and react for 8 h, separate with a magnet, wash, freeze-dry, and obtain a catalytic color developing factor.

[0097] Test Example 1

[0098] The specific surface area and pore volume of the catalytic color development factors prepared in Preparation Examples 1-3 or Comparative Preparation Examples 1-7 were tested using the AUTOSORB-1-C specific surface area and pore size analyzer produced by Quantachrome Corporation of the United States. The results are shown in Table 1.

[0099] Table 1

[0100] Group <![CDATA[Specific surface area (m 2 / g)]]> <![CDATA[Total pore volume (cm 3 / g)]]> Preparation Example 1 665 0.613 Preparation Example 2 668 0.615 Preparation Example 3 670 0.619 Comparative Preparation Example 1 612 0.586 Comparative Preparation Example 2 644 0.604 Comparative Preparation Example 3 641 0.603 Comparative Preparation Example 4 637 0.598 Comparative Preparation Example 5 624 0.591 Comparative Preparation Example 6 584 0.547 Comparative Preparation Example 7 639 0.600

[0101] It can be seen from the above table that the catalytic color development factors prepared in Preparation Examples 1-3 of the present invention have higher specific surface areas and total pore volumes.

[0102] Example 1

[0103] The present embodiment provides a method for preparing a blood glucose test strip, comprising the following steps: dissolving 2 g of 3,3',5,5'-tetramethylbenzenediamine in 150 mL of ethanol, adding 9 g of the catalytic color development factor prepared in Preparation Example 1, dispersing at 1000 W ultrasonically for 15 min, spraying the mixture onto a PET film through a spraying device, with a spraying pressure of 2 bar, spraying for 5 s, and a spraying volume of 3 mL / cm 2 , freeze-dried, wrapped with a PET film, and leaving a blood contact hole and an observation hole to obtain a blood glucose test strip.

[0104] During the test, drop 0.1 mL of blood sample into the blood contact hole of the test paper and observe the blood sample after 5 minutes.

[0105] Observe the light transmittance of the test paper at the observation hole; use a mobile phone to analyze the gray value at the observation hole and use the standard curve to determine the sugar concentration.

[0106] Example 2

[0107] The present embodiment provides a method for preparing a blood glucose test strip, comprising the following steps: dissolving 4 g of 3,3',5,5'-tetramethylbenzenediamine in 150 mL of ethanol, adding 12 g of the catalytic color development factor prepared in Preparation Example 2, dispersing at 1000 W ultrasonically for 15 min, spraying the mixture onto a PET film through a spraying device, with a spraying pressure of 3 bar, spraying for 15 s, and a spraying volume of 5 mL / cm 2 , freeze-dried, wrapped with a PET film, and leaving a blood contact hole and an observation hole to obtain a blood glucose test strip.

[0108] During the test, drop 0.1 mL of blood sample into the blood contact hole of the test paper and observe the blood sample after 5 minutes.

[0109] Observe the light transmittance of the test paper at the observation hole; use a mobile phone to analyze the gray value at the observation hole and use the standard curve to determine the sugar concentration.

[0110] Example 3

[0111] The present embodiment provides a method for preparing a blood glucose test strip, comprising the following steps: dissolving 3 g of 3,3',5,5'-tetramethylbenzenediamine in 150 mL of ethanol, adding 10 g of the catalytic color development factor prepared in Preparation Example 3, dispersing at 1000 W ultrasonically for 15 min, spraying the mixture onto a PET film through a spraying device, with a spraying pressure of 2.5 bar, spraying for 10 s, and a spraying volume of 4 mL / cm 2 , freeze-dried, wrapped with a PET film, and leaving a blood contact hole and an observation hole to obtain a blood glucose test strip.

[0112] During the test, drop 0.1 mL of blood sample into the blood contact hole of the test paper and observe the blood sample after 5 minutes.

[0113] Observe the light transmittance of the test paper at the observation hole; use a mobile phone to analyze the gray value at the observation hole and use the standard curve to determine the sugar concentration.

[0114] Comparative Example 1

[0115] Compared with Example 3, the difference is that the catalytic color development factor is prepared by Comparative Preparation Example 1.

[0116] Comparative Example 2

[0117] Compared with Example 3, the difference is that the catalytic color development factor is prepared by Comparative Preparation Example 2.

[0118] Comparative Example 3

[0119] Compared with Example 3, the difference is that the catalytic color development factor is prepared by Comparative Preparation Example 3.

[0120] Comparative Example 4

[0121] Compared with Example 3, the difference is that the catalytic color development factor is prepared by Comparative Preparation Example 4.

[0122] Comparative Example 5

[0123] Compared with Example 3, the difference is that the catalytic color development factor is prepared by Comparative Preparation Example 5.

[0124] Comparative Example 6

[0125] Compared with Example 3, the difference is that the catalytic color development factor is prepared by Comparative Preparation Example 6.

[0126] Comparative Example 7

[0127] Compared with Example 3, the difference is that the catalytic color development factor is prepared by Comparative Preparation Example 7.

[0128] Test Example 1

[0129] According to the method, a certain gradient concentration of glucose solution was tested, and the linear range and detection limit of the blood glucose test strips prepared in Examples 1-3 or Comparative Examples 1-7 were established. The results are shown in Table 2.

[0130] Table 2

[0131] Group Linear range <![CDATA[Limit of detection (×10 -6 mol / L)]]> Example 1 <![CDATA[10 -5 Up to 10 -1 mol / L]]> 5 Example 2 <![CDATA[10 -5 Up to 10 -1 mol / L]]> 5 Example 3 <![CDATA[10 -5 Up to 10 -1 mol / L]]> 4 Comparative Example 1 <![CDATA[10 -5 Up to 10 -2 mol / L]]> 10 Comparative Example 2 <![CDATA[5×10 -5 Up to 5×10 -2 mol / L]]> 13 Comparative Example 3 <![CDATA[5×10 -5 Up to 5×10 -2 mol / L]]> 15 Comparative Example 4 <![CDATA[5×10 -5 Up to 5×10 -2 mol / L]]> 20 Comparative Example 5 <![CDATA[2×10 -5 Up to 10 -2 mol / L]]> 30 Comparative Example 6 <![CDATA[10 -5 Up to 5×10 -1 mol / L]]> 25 Comparative Example 7 <![CDATA[10 -5 Up to 10 -1 mol / L]]> 100

[0132] It can be seen from the above table that the blood glucose test strips prepared in Examples 1-3 of the present invention have a wider linear range and a lower detection limit.

[0133] Test Example 2

[0134] After the glucose detection method was established, the glucose concentration in the same blood sample was determined. The detection method was the same as above. The test was performed three times and the average value was taken. The results are shown in Table 3.

[0135] Table 3

[0136] Group Average measured value (mmol / L) RSD(%) Hospital measurement value 6.04 5.45 Example 1 6.12 1.02 Example 2 6.09 0.97 Example 3 6.07 0.95 Comparative Example 1 5.97 2.45 Comparative Example 2 5.95 3.52 Comparative Example 3 5.91 3.85 Comparative Example 4 5.89 4.15 Comparative Example 5 5.86 5.92 Comparative Example 6 5.84 5.24 Comparative Example 7 5.73 7.68

[0137] It can be seen from the above table that the measured values ​​of the blood glucose test strips prepared in Examples 1-3 of the present invention are close to the values ​​detected in the hospital, and the RSD values ​​are relatively low.

[0138] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for preparing a blood glucose test strip, characterized in that: The method comprises the following steps: dissolving 3,3',5,5'-tetramethylbenzidine in ethanol, adding a catalytic color development factor, uniformly dispersing by ultrasonication, spraying the mixture onto a PET film by means of a spraying device, freeze drying, coating the mixture with a PET film, and leaving a blood contact hole and an observation hole to obtain a blood glucose test strip; The preparation method of the catalytic color developing factor is as follows: S1. Preparation of mesoporous silica nanospheres: dissolving an alkyl orthosilicate in ethanol, adding a porogen, ammonia water and water, stirring the reaction, centrifuging, washing, drying and calcining to obtain mesoporous silica nanospheres; the alkyl orthosilicate is methyl orthosilicate or ethyl orthosilicate, the porogen is hexadecyltrimethylammonium chloride or hexadecyltrimethylammonium bromide, the mass ratio of the alkyl orthosilicate, ethanol, porogen, ammonia water and water is 10-12:70-100:1-2:4-6:5-7, the stirring reaction time is 10-12h, the calcination temperature is 400-500℃, and the time is 2-4h; S2. Preparation of Cu / Ce-doped magnetic mesoporous silica nanospheres: dissolve cupric chloride, cerium chloride, ferric chloride and ferrous chloride in water, add mesoporous silica nanospheres, add ammonia water dropwise under inert gas protection, heat and stir to react, centrifuge, wash, dry and calcine to obtain Cu / Ce-doped magnetic mesoporous silica nanospheres; the mass ratio of the cupric chloride, cerium chloride, ferric chloride, ferrous chloride, mesoporous silica nanospheres and ammonia water is 0.3-0.5:0.1-0.3:3.24:1.26:10:5-7, the temperature of the heating and stirring reaction is 80-90°C, the time is 3-5h, the temperature of the calcination is 350-450°C, and the time is 1-3h; S3. Loading of graphene oxide: adding Cu / Ce-doped magnetic mesoporous silica nanospheres to an aqueous dispersion of graphene oxide, stirring and mixing, and spray drying to obtain graphene oxide-loaded Cu / Ce-doped magnetic mesoporous silica nanospheres; the concentration of the aqueous dispersion of graphene oxide is 0.5-1.5 mg / mL, and the solid-liquid ratio of the Cu / Ce-doped magnetic mesoporous silica nanospheres to the aqueous dispersion of graphene oxide is 1:3-5 g / mL; S4. Tannic acid modification: adding graphene oxide loaded Cu / Ce doped magnetic mesoporous silica nanospheres to water, adding tannic acid and a catalyst, heating and stirring the reaction, separating with a magnet, washing, and drying to obtain modified graphene oxide loaded Cu / Ce doped magnetic mesoporous silica nanospheres; the mass ratio of the graphene oxide loaded Cu / Ce doped magnetic mesoporous silica nanospheres, tannic acid, and the catalyst is 10:3-4:0.5-1, the catalyst is a Tris-HCl solution with a pH of 8.5-9.5, the temperature of the heating and stirring reaction is 50-60°C, and the time is 2-4h; S5. Fixing glucose oxidase: Add modified graphene oxide loaded Cu / Ce doped magnetic mesoporous silica nanospheres into water, add NHS and EDC, stir to activate, add glucose oxidase, stir to react, separate with a magnet, wash, freeze-dry, and obtain a catalytic color factor; the mass ratio of the modified graphene oxide loaded Cu / Ce doped magnetic mesoporous silica nanospheres, NHS, EDC and glucose oxidase is 10:3-4:2-3:3-5, the stirring activation time is 20-40min, and the stirring reaction time is 7-10h.

2. The preparation method according to claim 1, characterized in that: The mass ratio of the 3,3',5,5'-tetramethylbenzenediamine to the catalytic color development factor is 2-4:9-12.

3. The preparation method according to claim 1, characterized in that: The spraying pressure is 2-3 bar, the spraying time is 5-15 seconds, and the spraying volume is 3-5 mL / cm 2 .

4. A blood glucose test strip prepared by the preparation method according to any one of claims 1 to 3.