TiO2 nanoparticle-enhanced urine catecholamine SERS (Surface Enhanced Raman Scattering) detection test paper and preparation method thereof

Abstract

The invention belongs to the field of biomedical detection, and particularly relates to urine catecholamine SERS (Surface Enhanced Raman Scattering) detection test paper based on TiO2 nanoparticle enhancement and a preparation method. The problems that equipment formed by a common technology is complex, operation is tedious, and time is long are solved. Comprising TiO2 nanoparticles and an SERS test paper body, and the SERS test paper body is evenly coated with the TiO2 nanoparticles. The operation method is simple and efficient, the process of detecting the catecholamine in the urine can be completed within 5 minutes, the treatment time is short, the detection range of the catecholamine is 10 <-3 > M to 10 <-6 > M, and the level of the catecholamine from high concentration to low concentration can be effectively detected.

Description

Technical Field

[0001] The invention belongs to the field of biomedical detection, and specifically relates to a urine catecholamine SERS detection test paper based on TiO2 nanoparticle enhancement and a preparation method thereof. Background Art

[0002] Catecholamines, including dopamine, norepinephrine and epinephrine, are important neurotransmitters and hormones in the human body, involved in regulating a variety of physiological functions, such as nerve conduction, blood pressure control and stress response. Abnormal secretion of catecholamine levels may indicate potential health problems, such as diseases such as pheochromocytoma. Therefore, the development of a rapid, sensitive and non-invasive method for catecholamine detection is of great clinical significance.

[0003] The detection methods of catecholamines include high performance liquid chromatography, enzyme-linked immunosorbent assay, etc. However, the above detection methods have problems such as complex equipment, cumbersome operation, and long time.

[0004] Therefore, it is urgent to propose a urine catecholamine SERS detection test strip based on TiO2 nanoparticle enhancement and a preparation method to solve the above technical problems. Summary of the invention

[0005] In order to solve the problems of complex equipment, cumbersome operation and long time formed by conventional technology, the present invention provides a brief overview of the present invention below to provide a basic understanding of certain aspects of the present invention. It should be understood that this overview is not an exhaustive overview of the present invention. It is not intended to determine the key or important parts of the present invention, nor is it intended to limit the scope of the present invention.

[0006] The technical solution of the present invention:

[0007] A urine catecholamine SERS detection test paper based on TiO2 nanoparticle enhancement, comprising the TiO2 nanoparticle enhanced urine catecholamine SERS detection test paper consisting of TiO2 nanoparticles and SERS test paper;

[0008] The TiO2 nanoparticles are uniformly coated on the SERS detection test paper.

[0009] Preferably, the SERS test paper is a PET strip with a length of 4 cm and a width of 1 cm, an aluminum foil is provided on the top of the PET strip, and the TiO2 nanoparticles are evenly coated on the aluminum foil.

[0010] A method for preparing a urine catecholamine SERS detection test paper based on TiO2 nanoparticle enhancement comprises the following steps;

[0011] Step 1: Tetrabutyl titanate and thioglycolic acid are dropped into ethanol, the reaction solution is stirred, and then deionized water is injected into the reaction solution and stirred. After the stirring is completed, the prepared TiO2 sample is collected by centrifugation, and the prepared TiO2 sample is further washed with ethanol and dried in an oven to obtain TiO2 nanoparticles;

[0012] Step 2: Cut the PET film into several strips of 4 cm long and 1 cm wide, and stick a circular aluminum foil with a diameter of 0.66 cm on the top of the PET strip;

[0013] Step 3: Disperse TiO2 nanoparticles in deionized water, grind in a mortar for 15 minutes, centrifuge, redisperse in anhydrous ethanol, accurately drop onto the surface of aluminum foil, and then dry at room temperature to prepare a urine catecholamine SERS detection test paper based on TiO2 nanoparticle enhancement.

[0014] Preferably, the mass ratio of each substance in step 1 is 0.5 mL of tetrabutyl titanate, 30 μL of thioglycolic acid, 70 mL of ethanol, and 1 mL of deionized water.

[0015] Preferably, the stirring time in step 1 is 3 hours and the drying time is 12 hours.

[0016] Preferably: step 1 is prepared under a vacuum environment.

[0017] The present invention has the following beneficial effects:

[0018] The present invention develops a urine catecholamine SERS test strip based on TiO2 nanoparticle enhancement, which has a simple and efficient operation method;

[0019] The process of detecting catecholamines in urine can be completed within 5 minutes, and the processing time is short;

[0020] The detection range of catecholamines in the test paper prepared by the present invention is 10 -3 M~10 -6 M, can effectively detect catecholamine levels from high to low concentrations. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a scanning electron microscope image of TiO2 nanoparticles;

[0022] Figure 2 is the transmission image of TiO2 nanoparticles;

[0023] Figure 3 This is an actual picture of the SERS test paper;

[0024] Figure 4 This is a picture of the actual use of SERS test paper;

[0025] Figure 5 This is a comparison of the SERS test paper before and after use;

[0026] Figure 6 This is a comparison of the SERS signals obtained by the SERS test paper for three catecholamines;

[0027] Figure 7 This is the detection range diagram of SERS test paper for dopamine;

[0028] Figure 8 This is the detection range diagram of SERS test paper for adrenaline;

[0029] Fig. 9 This is the detection range diagram of SERS test paper for norepinephrine. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention is described below by the specific embodiments shown in the accompanying drawings. However, it should be understood that these descriptions are only exemplary and are not intended to limit the scope of the present invention. In addition, in the following description, the description of well-known structures and technologies is omitted to avoid unnecessary confusion of the concept of the present invention.

[0031] Specific implementation method 1: Combination Figure 1-Figure 9 The present embodiment is described. The present embodiment is a urine catecholamine SERS detection test paper based on TiO2 nanoparticle enhancement, comprising the TiO2 nanoparticle enhanced urine catecholamine SERS detection test paper consisting of TiO2 nanoparticles and SERS test paper;

[0032] The TiO2 nanoparticles are uniformly coated on the SERS detection test paper.

[0033] In order to enhance the interaction with catecholamine molecules, the TiO2 surface can also be chemically modified, for example, by introducing functional molecules such as amino groups, carboxyl groups, etc., to increase its affinity for catecholamines.

[0034] The size of TiO2 nanoparticles is between 1-50 nanometers. Smaller particles have a larger specific surface area, which is conducive to enhancing the SERS signal; the shape of the particles can be spherical or nanorod-shaped, which can also enhance the effect; the concentration of TiO2 nanoparticles is between 0.01-1 mg / mL, which can greatly improve the sensitivity and accuracy of SERS test paper.

[0035] Specific implementation method 2: Combination Figure 1-Figure 9The present embodiment is described as a urine catecholamine SERS detection test paper based on TiO2 nanoparticle enhancement. The SERS detection test paper is a PET strip with a length of 4 cm and a width of 1 cm. An aluminum foil sticker is provided on the top of the PET strip, and TiO2 nanoparticles are evenly coated on the aluminum foil sticker. The SERS detection test paper adopts an innovative material combination and design, combining the structure of a PET substrate, an aluminum foil reflective layer and a TiO2 nanoparticle coating to achieve an efficient signal enhancement mechanism.

[0036] Microstructures or nanopores are further fabricated on the aluminum surface by laser etching or electrochemical methods to further enhance the local electromagnetic field and thus improve the SERS signal.

[0037] Specific implementation method three: Combination Figure 1-Figure 9 The present embodiment is described. A method for preparing a urine catecholamine SERS detection test paper based on TiO2 nanoparticle enhancement in the present embodiment comprises the following steps:

[0038] Step 1: drop 0.5 mL of analytical grade tetrabutyl titanate and 30 μL of 99% thioglycolic acid into 70 mL of analytical grade anhydrous ethanol, stir the reaction solution for 3 hours, then inject 1 mL of deionized water into the reaction solution, stir for 3 hours under vacuum, after stirring, collect the prepared TiO2 sample by centrifugation, further wash the prepared TiO2 sample with ethanol, and dry it in an oven for 12 hours to obtain TiO2 nanoparticles;

[0039] Step 2: Cut the PET film into several strips of 4 cm long and 1 cm wide, and stick a circular aluminum foil with a diameter of 0.66 cm on the top of the PET strip;

[0040] Step 3: Disperse TiO2 nanoparticles in deionized water, grind in a mortar for 15 minutes, centrifuge, redisperse in anhydrous ethanol, accurately drop onto the surface of aluminum foil, and then dry at room temperature to prepare a urine catecholamine SERS detection test paper based on TiO2 nanoparticle enhancement.

[0041] Furthermore, in the synthesis of TiO2 nanoparticles, doping with metal elements such as silver, gold, copper, etc. or non-metal elements such as nitrogen, sulfur, etc. can further improve the SERS enhancement effect of TiO2 and increase its selectivity and sensitivity to catecholamines;

[0042] Aluminum foil stickers can use multi-layer aluminum foil or microstructured metal substrates to increase the local electric field effect, thereby enhancing the SERS signal. The microstructures on the surface of the aluminum foil sticker substrate are nanopores, nanostripes, etc., which can further enhance the signal amplification effect;

[0043] In addition to dripping, other techniques such as spraying, sol-gel method or chemical vapor deposition can also be used. These methods can ensure that the TiO2 nanoparticles are evenly distributed on the surface of the aluminum foil, thereby maximizing the enhancement effect;

[0044] After the TiO2 nanoparticles are added dropwise, low temperature drying such as 30-40°C or vacuum drying may be used to avoid agglomeration of TiO2 particles or deformation of the substrate caused by high temperature, while maintaining the dispersibility and surface activity of TiO2.

[0045] The PET film and aluminum foil can be purchased in offline stores and are easy to obtain.

[0046] Example 1

[0047] 0.5 mL of tetrabutyl titanate and 30 μL of thioglycolic acid were dropped into 70 mL of ethanol, and the reaction solution was stirred for 3 h. Then 1 mL of deionized water was injected into the reaction solution, and stirred for 3 h at room temperature. The prepared TiO2 sample was collected by centrifugation. The prepared TiO2 sample was further washed with ethanol several times and dried in an oven for 12 h.

[0048] The purchased PET film was cut into several strips of 4 cm in length and 1 cm in width. A circular aluminum foil with a diameter of about 0.66 cm was pasted on the top of the PET strip. The synthesized TiO2 nanoparticles were dispersed in deionized water, ground in a mortar for more than 15 minutes, centrifuged, and redispersed in anhydrous ethanol to prepare a TiO2 nanomaterial suspension;

[0049] Accurately drop the TiO2 nanomaterial suspension onto the surface of the aluminum foil and dry it at room temperature for later use;

[0050] Human urine was used as solvent to prepare urine containing different concentrations of catecholamines (10 -3 M~10 -6 M) The prepared SERS test paper was directly immersed in the solution for 5 minutes and then continuous SERS measurement was immediately performed to obtain SERS spectrum information of different catecholamines under 532 nm laser excitation. The data acquisition time was 5 s, accumulated once, and the power was 10 mW.

[0051] The instrument used was a confocal Raman microscope RTS2-301-DL purchased from Beijing Zhuoli Hanguang Instrument Co., Ltd.

[0052] TiO2 nanoparticles can also be synthesized by taking 70mL of anhydrous ethanol in a 250mL three-hole flask, adding 30μL of thioglycolic acid, stirring at room temperature for 15 minutes, then adding 500μL of tetrabutyl titanate to the three-hole flask, and immediately evacuating the three-hole flask after the addition. After stirring at room temperature for 6 hours, a certain amount of deionized water is added to the reaction liquid system, stirred at room temperature for 6 hours, centrifuged, washed with anhydrous ethanol several times, and dried at 40°C for 8 hours.

[0053] It should be noted that in the above embodiments, as long as the technical solutions are not contradictory, they can be arranged and combined, and those skilled in the art can exhaust all possibilities based on the mathematical knowledge of arrangement and combination. Therefore, the present invention will no longer describe the technical solutions after arrangement and combination one by one, but it should be understood that the technical solutions after arrangement and combination have been disclosed by the present invention.

[0054] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A urine catecholamine SERS test strip enhanced by TiO2 nanoparticles, characterized in that: The TiO2 nanoparticle-enhanced urine catecholamine SERS test paper is composed of TiO2 nanoparticles and SERS test paper; The TiO2 nanoparticles are uniformly coated on the SERS test paper.

2. The urine catecholamine SERS test strip based on TiO2 nanoparticle enhancement according to claim 1, characterized in that: The SERS test paper is a PET strip with a length of 4 cm and a width of 1 cm. An aluminum foil is provided on the top of the PET strip, and TiO2 nanoparticles are evenly coated on the aluminum foil.

3. A method for preparing a urine catecholamine SERS test strip enhanced by TiO2 nanoparticles, characterized in that: The method comprises the following steps: Step 1: Tetrabutyl titanate and thioglycolic acid are dropped into ethanol and stirred evenly to obtain a reaction solution, and then deionized water is injected into the reaction solution and stirred. After the stirring is completed, the prepared TiO2 sample is collected by centrifugation, and the prepared TiO2 sample is further washed with ethanol and dried in an oven to obtain TiO2 nanoparticles; Step 2: Cut the PET film into several strips of 4 cm long and 1 cm wide, and stick a circular aluminum foil with a diameter of 0.66 cm on the top of the PET strip; Step 3: Disperse TiO2 nanoparticles in deionized water, grind in a mortar for 15 minutes, centrifuge, redisperse in anhydrous ethanol, accurately drop onto the surface of aluminum foil, and then dry at room temperature to prepare a urine catecholamine SERS detection test paper based on TiO2 nanoparticle enhancement.

4. The method for preparing a urine catecholamine SERS test paper based on TiO2 nanoparticle enhancement according to claim 3, characterized in that: The mass ratio of each substance in step 1 is 0.5 mL of tetrabutyl titanate, 30 μL of thioglycolic acid, 70 mL of ethanol, and 1 mL of deionized water.

5. The method for preparing a urine catecholamine SERS test paper based on TiO2 nanoparticle enhancement according to claim 3, characterized in that: In step 1, the stirring time is 3 h and the drying time is 12 h.

6. The method for preparing a urine catecholamine SERS test paper based on TiO2 nanoparticle enhancement according to claim 3, characterized in that: The step 1 is prepared under a vacuum environment.

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