CN109975281B - Preparation method of test paper for detecting organophosphorus pesticide - Google Patents
Preparation method of test paper for detecting organophosphorus pesticide Download PDFInfo
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- CN109975281B CN109975281B CN201910227758.1A CN201910227758A CN109975281B CN 109975281 B CN109975281 B CN 109975281B CN 201910227758 A CN201910227758 A CN 201910227758A CN 109975281 B CN109975281 B CN 109975281B
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Abstract
The invention relates to a test paper for rapidly detecting organophosphorus pesticide, which comprises the following components in part by weight: by utilizing a multilayer composite means, the liquid to be detected containing the organophosphorus passes through the upper, middle and lower layers of filter paper which are fixed with different reagents and have different functions respectively, so that the aim of rapidly detecting the organophosphorus pesticide by utilizing a color development method is fulfilled. Firstly, each layer of filter paper is printed with a water passing area and a water blocking area by a wax spraying printer, then a hydrophobic adsorption material is fixed in the water passing area of the upper layer of filter paper, a buffer salt is fixed in the water passing area of the middle layer of filter paper, an oxidation-reduction color developing agent is fixed in the water passing area of the lower layer of filter paper, and a film is tightly attached to the bottom of the lower layer of filter paper. Organic phosphorus is adsorbed by hydrophobicity in the process of permeating the upper layer, is continuously concentrated and enriched in the upper layer filter paper, then enters the lower layer after the pH value is adjusted by alkaline hydrolysis and buffer salt fixed in the middle layer, is oxidized by the oxidant of the lower layer, generates color change after the oxidant is reduced, and judges whether organic phosphorus pesticide exists or not through the color change.
Description
Technical Field
The invention relates to a method for preparing test paper capable of rapidly detecting organophosphorus pesticides by superposing three layers of filter paper with enrichment, buffering and color development functions by a multilayer compounding means.
Background
Organophosphorus pesticides, which are organic compounds containing phosphorus elements, are mostly phosphates or thiophosphates, have the advantages of broad spectrum, high efficiency, multiple action modes, short half-life period and the like, and are widely applied to agricultural production. However, long-term application of the pesticide not only causes residues with different degrees in crops, but also pollutes soil, water and air, causes serious environmental problems and threatens human health. The technology for detecting organophosphorus pesticide residues has been studied, and the existing detection means include chromatography (such as gas chromatography, high performance liquid chromatography, gas chromatography-mass spectrometry, liquid chromatography-mass spectrometry, and the like), spectroscopy, a biosensor method, an enzyme-linked immunosorbent assay, a molecular imprinting method, and an enzyme inhibition method generally adopted in the field of organophosphorus rapid detection.
The basic principle of the enzyme inhibition method is that according to the inhibition effect of the organophosphorus pesticide on the activity of acetylcholinesterase, the enzyme inhibition rate is measured by utilizing the chromogenic reaction between enzyme and a substrate, and then the quantitative analysis of the organophosphorus pesticide is realized. Its main advantages are low cost, high sensitivity and simple operation. The enzymatic test paper developed based on the enzyme inhibition method is a main means for realizing on-site quick detection of pesticide residues without depending on an instrument, but has the problems that the requirement of enzymatic reaction on temperature is high, the temperature needs to be kept constant at 37 ℃ for 3-5 minutes, and the enzymatic test paper is difficult to realize in actual operation.
Organic phosphorus is hydrolyzed under alkaline conditions to generate a reductive hydrolysate, and after the reductive hydrolysate reacts with an oxidant such as potassium permanganate or ferric chloride, the oxidant can generate color change, and the content of the organic phosphorus can be judged by comparing the change degree with a colorimetric card, so that a feasible basis is provided for the preparation technology of the test paper for detecting the organophosphorus pesticide.
Disclosure of Invention
The invention aims to solve the technical problem of realizing the on-site quick detection of organophosphorus pesticide residues by means of multilayer composite test paper based on color reaction.
In order to achieve the purpose, the invention adopts the following technical scheme:
a preparation method of test paper for detecting organophosphorus pesticide is characterized by comprising the following steps: the test paper is divided into an upper layer, a middle layer and a lower layer, a water passing area and a water blocking area are printed out through a wax spraying printer, wherein a hydrophobic adsorption material is fixed in the upper layer test paper water passing area, buffer salt is fixed in the middle layer filter paper water passing area, an oxidation-reduction color developing agent is fixed in the lower layer filter paper water passing area, and a thin film is tightly attached to the bottom of the lower layer filter paper to prevent liquid leakage. When a sample to be detected is detected, firstly, liquid to be detected is dropped onto the water passing area on the upper layer, a water absorbing material is filled below the water passing area, so that an organic phosphorus solution is continuously concentrated and enriched in the process of flowing through the hydrophobic adsorption material, then the water absorbing material below the filter paper is removed, the upper layer, the middle layer and the lower layer are attached together, and the hydrophilic areas are mutually overlapped to form a three-layer composite structure. Then, a strong base solution is dripped on the upper layer, organic phosphorus is hydrolyzed by the strong base solution and then eluted from the silica gel adsorption material, enters a middle buffer salt area, permeates into the lower layer after the pH value is adjusted, and is subjected to oxidation-reduction reaction with an oxidant on the lower layer, the oxidant is reduced to generate color change, the filter paper on the lower layer is peeled, and qualitative and quantitative analysis on the organic phosphorus is realized by judging the color change intensity of the oxidant.
The organophosphorus pesticide comprises dichlorvos, dimethoate, phoxim, parathion, omethoate, methamidophos, chlorpyrifos, acephate, malathion, triazophos, fenitrothion, glyphosate, tolclofos-methyl, pyrifenozide, trichlorfon, profenofos, phoxim, fenthion, pyrazofos, phenthoate, phos, fenamiphos, diazinon, oxydisup, phorate, chlorpyrifos-methyl, parathion-methyl, glufosinate-methyl, ethoprophos-p, triazophos, pyrazofos-methyl, fenthion-methyl, pirimiphos-methyl, fenthion-methyl, phoxim-methyl, quinalphos, phofos-methyl, terbufos, fenthion, phos-ethyl, ethiophos, ethylbromophos, ethephon, fenamiphos, fenthion, thiochloride, fosthiazate, ethion, isoprothion, isoprothiolane, ethoprophos-methyl, Terbufos, gossypos, fenitrothion, phosphorus of vegetables and fruits, coumaphos, fenitrothion, methoprophos, pyridaphethione, fluthion, prothiochlor and systemic phos.
The water passing area is a circle with the diameter of 1-10 mm, preferably a circle with the diameter of 1-7 mm, and most preferably a circle with the diameter of 2-4 mm. The diameter is too small, water drops float on the water-blocking wax due to the surface tension of the solution, and the water passing speed is extremely slow or difficult; if the diameter is too large, the solution will flow through the center without spreading rapidly to the edges of the circle, making it difficult to achieve a uniform color change.
The water blocking area is formed by uniformly printing wax melted by wax spraying printing on filter paper according to a design pattern in a liquid drop mode with the diameter of 50-60 mu m, quickly solidifying, and heating for 0.5-10 minutes at 80-150 ℃ in an oven to completely melt the wax and permeate the wax into fibers of the filter paper.
The hydrophobic adsorption material is hydrophobic silica gel, and the specific surface area is 300-800 m2One or two octadecyl silane bonded silica gel fillers C18 in hydrophobic silica gel particles with the particle size of 10-60 mu m or C18 adsorbing materials, wherein the fixed amount is 10-20 mg/cm2。
The water absorbing material is one of absorbent cotton, high molecular water absorbing polymer and filter paper.
The alkali solution is 0.5-1.0M of one or more of sodium hydroxide, potassium hydroxide, sodium ethoxide and ammonium hydroxide, and the using amount is 0.2-0.5 mL.
And the buffer salt area is formed by dripping 200-300 mu L of 0.02-0.2M buffer solution with the pH adjusting capacity of 6.0-7.5 on the hydrophilic area of the middle layer test paper, and the buffer solution comprises one or more than two of citric acid-sodium citrate, disodium hydrogen phosphate-sodium dihydrogen phosphate, disodium hydrogen phosphate-potassium dihydrogen phosphate and potassium dihydrogen phosphate-sodium hydroxide systems, and is dried for later use.
The redox color developing agent is potassium permanganate or ferric chloride, and the fixed quantity on the hydrophilic region is 0.1-1.0 mg/cm2。
The film is one of PET, PTFE and PVC film.
The detection process is as follows: dripping 500 mu L of solution to be detected on the upper layer filter paper, removing the water absorbing material after the solution is absorbed by the lower water absorbing material, overlapping the upper layer filter paper and the middle and lower layer filter paper to enable hydrophilic areas to be overlapped, dripping alkali liquor on the overlapped filter paper, standing for 5 minutes, removing the upper and lower layer filter paper, observing the color change of the indicator of the lower layer filter paper, and judging whether the solution to be detected contains the organophosphorus pesticide. The test paper is loaded with potassium permanganate, and if the organophosphorus pesticide exists, the color of the test paper changes from red to light red to yellow; if the organophosphorus pesticide exists in the test paper immobilized with ferric chloride, the color of the test paper changes from yellow to light yellow to white.
The invention has the following advantages:
1. hydrophobic organic phosphorus in the fruit and vegetable eluent is adsorbed by the application of a hydrophobic adsorption material, so that a complicated sample pretreatment process and the use of a toxic organic solvent are avoided;
2. the alkaline hydrolysis and the buffer neutralization of the organic phosphorus are completed on the test paper in one step, so that the trouble of reaction in the solution and then dropwise adding acid liquor for neutralization is reduced;
3. the whole organophosphorus detection is completed by overlapping the upper layer test paper, the middle layer test paper and the lower layer test paper, and the operation is simple and easy;
4. the test paper is low in price, environment-friendly and suitable for rapid field detection.
Drawings
FIG. 1 is a schematic diagram of a test paper for detecting organophosphorus pesticides.
FIG. 2 is a response diagram of organophosphorus test paper using potassium permanganate as oxidant
a) Potassium permanganate original image b) figure in which potassium permanganate was reduced.
FIG. 3 is a response diagram of the organophosphorus test paper using ferric chloride as an oxidant.
a) Original figure of ferric chloride b) figure in which ferric chloride is reduced
FIG. 4 is a graph showing the response of test paper for detecting organophosphorus pesticide to dimethoate with different concentrations.
FIG. 5 is a linear response curve of organophosphorus pesticide test paper (potassium permanganate) for detecting dimethoate with different concentrations.
Detailed Description
The present invention is described in further detail below with reference to examples, but it should not be construed that the present invention is limited to the examples, and any technologies implemented based on the present invention should be considered as the scope of the present invention.
Example 1
Three sheets of 2x2cm2The filter paper is uniformly printed with a layer of wax by a wax spraying printer, a blank circular water passing area with the diameter of 3mm is reserved in the center, and the waxed filter paper is placed in an oven to be dried for 2 minutes at the temperature of 150 ℃ so that the wax is uniformly dissolved and permeates into the fiber of the filter paper to form a water blocking area. Dripping C18 powder uniformly dispersed with ethanol in the water passing region of the upper layer filter paper at a fixed amount of 10mg/cm2Drying for later use; in the middle layer filterDripping 250 mu L of 0.025M sodium dihydrogen phosphate-disodium hydrogen phosphate buffer solution into a water-passing area of the paper, and drying for later use; dripping 35 microliter of 1g/L potassium permanganate solution into the water passing area of the lower layer filter paper to fix the solution at 0.5mg/cm2The potassium permanganate is dried for standby, and a PET film is adhered to the bottom of the lower layer of filter paper, as shown in figure 1.
The pear epidermis is cleaned by clear water, and a dimethoate standard sample is dripped into the cleaning solution to ensure that the concentration of the dimethoate standard sample reaches about 1 ppm. And (3) dropwise adding 500 mu L of the labeling solution into a water passing area of the upper layer of filter paper, placing the pad with a water absorbing material, after the solution completely flows through the upper layer of filter paper, overlapping the upper layer of filter paper with the middle and lower layers of filter paper, dropwise adding 50 mu L of 1.0M NaOH solution, standing for 5 minutes, removing the upper layer of filter paper and the middle layer of filter paper, as shown in figure 2, showing that the color of potassium permanganate in the water passing area of the lower layer of filter paper is obviously changed and changed from red to yellow, and verifying that the organophosphorus pesticide exists in a pear sample of the labeling dimethoate.
Example 2
Three sheets of 2x2cm2The filter paper is uniformly printed with a layer of wax by a wax spraying printer, a blank circular water passing area with the diameter of 3mm is reserved in the center, and the waxed filter paper is placed in an oven to be dried for 10 minutes at 90 degrees, so that the wax is uniformly dissolved and permeates into the fiber of the filter paper to form a water blocking area. Dripping hydrophobic silica gel particles uniformly dispersed with ethanol on the water passing area of the upper layer filter paper, wherein the fixed amount is 20mg/cm2Drying for later use; dripping 250 mu L of citric acid-sodium citrate buffer solution of 0.2M into the water passing area of the middle layer filter paper, and drying for later use; dripping 35 microliter of 2g/L ferric chloride solution into the ferric chloride dropped into the water passing area of the lower layer filter paper to make the fixed quantity be 1mg/cm2And drying for later use, wherein the bottom of the lower layer of filter paper is adhered with a PET film as shown in figure 1.
The skin of the Chinese cabbage is cleaned by clear water, and a dipterex standard sample is dripped into the cleaning solution to ensure that the concentration of the dipterex standard sample reaches about 1 ppm. Dropwise adding 500 mu L of the standard adding solution into a water passing area of the upper layer of filter paper, placing the pad with a water absorbing material, after the solution completely flows through the upper layer of filter paper, overlapping the upper layer of filter paper with the middle and lower layers of filter paper, dropwise adding 100 mu L of 0.8M KOH solution, standing for 5 minutes, removing the upper and middle layers of filter paper, so that the color of ferric chloride in the water passing area of the lower layer of filter paper is obviously changed, and the test paper is changed from yellow to white, as shown in figure 3, the fact that the cabbage sample with the standard adding dipterex contains the organic phosphorus pesticide can be verified.
Example 3
Three sheets of 2x2cm2The filter paper is uniformly printed with a layer of wax by a wax spraying printer, a blank circular water passing area with the diameter of 3mm is reserved in the center, and the waxed filter paper is placed in an oven to be dried for 2 minutes at the temperature of 150 ℃ so that the wax is uniformly dissolved and permeates into the fiber of the filter paper to form a water blocking area. Dripping C18 powder uniformly dispersed with ethanol in the water passing region of the upper layer filter paper at a fixed amount of 15mg/cm2Drying for later use; dripping 250 μ L of 0.025M buffer solution of sodium dihydrogen phosphate-disodium hydrogen phosphate in the water passing region of the middle layer filter paper, and blow-drying for use; dripping potassium permanganate into the water passing area of the lower layer filter paper, and dripping 35 microliters of 1g/L potassium permanganate solution to ensure that the fixed quantity is 0.5mg/cm2And drying for later use, wherein the bottom of the lower layer of filter paper is adhered with a PET film.
Washing tomato skin with clear water, dripping a dimethoate standard sample into the washing solution to enable the concentration to reach about 0.5, 1, 1.5, 2 and 2.5ppm respectively, dripping 500 mu L of the standard-added solution into a water passing area of upper filter paper respectively, putting a pad with a water absorbing material, after the solution completely flows through the upper filter paper, overlapping the upper filter paper and middle and lower filter paper, dripping 50 mu L of 1.0M NaOH solution, standing for 5 minutes, removing the upper and middle filter paper, and showing that the color of potassium permanganate in the water passing area of the lower filter paper is gradually changed along with the increase of the concentration of the standard-added pesticide dimethoate, and the color is gradually changed from red to yellow as shown in figure 4. A good correlation relationship can be obtained by making a curve of potassium permanganate color values (squares of three channels of red, green and blue) corresponding to each concentration and the dimethoate concentration, as shown in figure 5, the tomato sample of the dimethoate with the standard can be verified to contain the organophosphorus pesticides, the color change intensity of the test paper is increased along with the increase of the concentration of the organophosphorus pesticides, and when the concentration of the dimethoate with the standard reaches 0.8ppm, the color change tends to be saturated, so that the test paper has good response to the organophosphorus pesticides with low concentrations, and the semi-quantitative detection of the pesticides with low concentrations can be realized.
Example 4
Three sheets of 2x2cm2The filter paper is uniformly printed with a layer of wax by a wax spraying printer, a blank circular water passing area with the diameter of 3mm is reserved in the center, and the waxed filter paper is placed in an oven to be dried for 8 minutes at 110 ℃ so that the wax is uniformly dissolved and permeates into the fiber of the filter paper to form a water blocking area. Dripping hydrophobic silica gel particles uniformly dispersed by ethanol on a water passing area of the upper layer filter paper, wherein the fixed amount of the hydrophobic silica gel particles is 18mg/cm2Drying for later use; dripping 250 mu L of citric acid-sodium citrate buffer solution of 0.2M into the water passing area of the middle layer filter paper, and drying for later use; dripping ferric chloride aqueous solution into the water passing area of the lower layer filter paper, dripping 28 microliter of 2g/L ferric chloride solution to form solid loading amount of 0.8mg/cm2The test paper is dried for standby, and a PET film is adhered to the bottom of the lower layer of filter paper.
The skin of the peach is cleaned by clear water, and a dipterex standard sample is dripped into the cleaning solution to ensure that the concentration of the dipterex standard sample reaches about 1 ppm. And dropwise adding 500 mu L of the labeling solution into a water passing area of the upper layer of filter paper, placing the pad with a water absorbing material, after the solution completely flows through the upper layer of filter paper, overlapping the upper layer of filter paper with the middle and lower layers of filter paper, dropwise adding 100 mu L of 0.8M KOH solution, standing for 5 minutes, removing the upper and middle layers of filter paper, and thus, the color of ferric chloride in the water passing area of the lower layer of filter paper is obviously changed from yellow to light yellow.
Example 5
Three sheets of 2x2cm2The filter paper is uniformly printed with a layer of wax by a wax spraying printer, a blank circular water passing area with the diameter of 3mm is reserved in the center, and the waxed filter paper is placed in an oven to be dried for 2 minutes at the temperature of 150 ℃ so that the wax is uniformly dissolved and permeates into the fiber of the filter paper to form a water blocking area. Dripping C18 powder uniformly dispersed with ethanol in the water passing region of the upper layer filter paper at a fixed amount of 10mg/cm2Drying for later use; dripping 250 mu L of 0.025M sodium dihydrogen phosphate-disodium hydrogen phosphate buffer solution into the water passing area of the middle layer filter paper, and drying for later use; dripping 35 microliter of 1g/L potassium permanganate solution into the water passing area of the lower layer filter paper to fix the solution at 0.5mg/cm2The potassium permanganate is dried for standby, and a PET film is adhered to the bottom of the lower layer of filter paper, as shown in figure 1.
Celery is cleaned by clear water, and a trichlorfon standard sample is dripped into the cleaning solution to ensure that the concentration of the trichlorfon standard sample reaches about 1 ppm. And dropwise adding 500 mu L of the standard solution into a water passing area of the upper layer of filter paper, placing the pad with a water absorbing material, after the solution completely flows through the upper layer of filter paper, overlapping the upper layer of filter paper with the middle and lower layers of filter paper, dropwise adding 50 mu L of 1.0M NaOH solution, standing for 5 minutes, removing the upper and middle layers of filter paper, and thus, the color of potassium permanganate in the water passing area of the lower layer of filter paper is obviously changed and becomes yellow from red.
Example 6
Three sheets of 2x2cm2The filter paper is uniformly printed with a layer of wax by a wax spraying printer, a blank circular water passing area with the diameter of 3mm is reserved in the center, and the waxed filter paper is placed in an oven to be dried for 2 minutes at the temperature of 150 ℃ so that the wax is uniformly dissolved and permeates into the fiber of the filter paper to form a water blocking area. Dripping C18 powder uniformly dispersed with ethanol in the water passing region of the upper layer filter paper at a fixed amount of 15mg/cm2Drying for later use; dripping 250 μ L of 0.025M buffer solution of sodium dihydrogen phosphate-disodium hydrogen phosphate in the water passing region of the middle layer filter paper, and blow-drying for use; dripping potassium permanganate into the water passing area of the lower layer filter paper, and dripping 35 microliters of 1g/L potassium permanganate solution to ensure that the fixed quantity is 0.5mg/cm2And drying for later use, wherein the bottom of the lower layer of filter paper is adhered with a PET film.
Washing the broccoli with clear water, dropwise adding a phorate standard sample into the washing solution to enable the concentration of the phorate standard sample to reach about 0.5 ppm, 1ppm, 1.5 ppm, 2 ppm and 2.5ppm respectively, dropwise adding 500 mu L of the standard-added solution into a water passing area of upper-layer filter paper respectively, placing a pad with a water absorbing material, after the solution completely flows through the upper-layer filter paper, overlapping the upper-layer filter paper and middle-layer filter paper, dropwise adding 50 mu L of 1.0M NaOH solution, standing for 5 minutes, removing the upper-layer filter paper, and thus the color of potassium permanganate in the water passing area of the lower-layer filter paper is gradually changed along with the increase of the concentration of the standard-added pesticide dimethoate, and the potassium permanganate gradually changes from red to yellow.
Example 7
Three sheets of 2x2cm2The filter paper is uniformly printed with a layer of wax by a wax spraying printer, a blank circular water passing area with the diameter of 3mm is reserved in the center, and the waxed filter paper is placed in an oven to be dried for 8 minutes at 110 ℃ so that the wax is uniformly dissolved and permeates into the fiber of the filter paper to form a water blocking area. Dripping hydrophobic silica gel particles uniformly dispersed by ethanol on the water passing area of the upper filter paperThe fixed amount of the granules is 18mg/cm2Drying for later use; dripping 250 mu L of citric acid-sodium citrate buffer solution of 0.2M into the water passing area of the middle layer filter paper, and drying for later use; dripping ferric chloride aqueous solution into the water passing area of the lower layer filter paper, dripping 28 microliter of 2g/L ferric chloride solution to form solid loading amount of 0.8mg/cm2The test paper is dried for standby, and a PET film is adhered to the bottom of the lower layer of filter paper.
The skin of the strawberry is cleaned by clear water, and a phoxim standard sample is dropped into the cleaning solution to make the concentration reach about 1 ppm. And dropwise adding 500 mu L of the labeling solution into a water passing area of the upper layer of filter paper, placing the pad with a water absorbing material, after the solution completely flows through the upper layer of filter paper, overlapping the upper layer of filter paper with the middle and lower layers of filter paper, dropwise adding 100 mu L of 0.8M KOH solution, standing for 5 minutes, removing the upper and middle layers of filter paper, and thus, the color of ferric chloride in the water passing area of the lower layer of filter paper is obviously changed from yellow to light yellow.
Claims (10)
1. A test paper for detecting organophosphorus pesticide is characterized in that: the detection test paper comprises an upper layer of filter paper, a middle layer of filter paper and a lower layer of filter paper, wherein the three layers of filter paper are provided with an annular water blocking area soaked with wax and a water passing area surrounded by the annular water blocking area; a hydrophobic adsorption material is fixed in the upper filter paper water passing area, a buffer salt is fixed in the middle filter paper water passing area, an oxidation-reduction color developing agent is fixed in the lower filter paper water passing area, and the water passing areas of the upper, middle and lower layers of test paper are sequentially and correspondingly arranged from top to bottom; the hydrophobic adsorption material has a specific surface area of 300-800 m2One or two of hydrophobic silica gel particles with the particle size of 10-60 mu m or octadecylsilane bonded silica gel filler C18, wherein the fixed amount of the hydrophobic silica gel particles or the octadecylsilane bonded silica gel filler C18 in the water filtering area of the upper filter paper is 10-20 mg/cm2。
2. The test paper for detecting organophosphorus pesticide according to claim 1, wherein:
a layer of film is tightly attached or adhered to the bottom or right below the lower layer of filter paper to prevent liquid leakage; the film is one of PET, PTFE and PVC film.
3. The test paper for detecting organophosphorus pesticide according to claim 1, wherein:
the redox color developing agent is potassium permanganate or ferric chloride, and the fixed quantity of the redox color developing agent on the water passing area of the lower layer filter paper is 0.1-1.0 mg/cm2。
4. The test paper for detecting organophosphorus pesticide according to claim 1, wherein: the buffer salt comprises one or more of buffer salt combinations adopted by a citric acid-sodium citrate buffer system, a disodium hydrogen phosphate-sodium dihydrogen phosphate buffer system, a disodium hydrogen phosphate-potassium dihydrogen phosphate buffer system and a potassium dihydrogen phosphate-sodium hydroxide buffer system;
the buffer salt area is formed by dripping 200-300 mu L of 0.02-0.2M buffer solution with pH adjusting capacity of 6.0-7.5 on the hydrophilic area of the middle layer test paper, and drying for later use.
5. The test paper for detecting organophosphorus pesticide according to claim 1, 3 or 4, wherein: the water passing area is a circle with the diameter of 1-10 mm.
6. A method for preparing a test paper for detecting organophosphorus pesticides as described in any one of claims 1 to 5, which comprises:
the method comprises the following steps:
1) and printing out water blocking areas on the three layers of test paper through a wax spraying printer: the water blocking area is formed by uniformly printing molten wax on filter paper in a liquid drop mode with the diameter of 50-60 mu m according to a required annular pattern through wax spraying and printing, quickly solidifying the wax, and then heating for 0.5-10 minutes at 80-150 ℃ in an oven to completely melt the wax and permeate the wax into fibers of the filter paper; and a water passing area surrounded by the annular water blocking area is formed;
2) a hydrophobic adsorption material is fixed in the upper filter paper water passing area, buffer salt is fixed in the middle filter paper water passing area, and an oxidation-reduction color developing agent is fixed in the lower filter paper water passing area;
dripping hydrophobic silica gel particles dispersed by ethanol or octadecylsilane chemically bonded silica filler C18 on a water passing area of the upper layer filter paper, and drying for later use;
dripping buffer solution into the water passing area of the middle layer filter paper, and drying for later use;
and fixing a potassium permanganate solution or an iron oxide solution in a water passing area of the lower layer filter paper, and drying for later use.
7. The method for preparing the test paper for detecting organophosphorus pesticide according to claim 6, wherein: the bottom of the lower layer of filter paper is adhered with a film for preventing liquid from leaking.
8. The use of a test strip for detecting organophosphorus pesticides as defined in any one of claims 1 to 5, wherein: the method is used for detecting the organophosphorus pesticide;
the organophosphorus pesticide comprises dichlorvos, dimethoate, phoxim, parathion, omethoate, methamidophos, chlorpyrifos, acephate, malathion, triazophos, fenitrothion, glyphosate, tolclofos-methyl, pyrifenozide, trichlorfon, profenofos, phoxim, fenthion, pyrazofos, phenthoate, phos, fenamiphos, diazinon, oxydisup, phorate, chlorpyrifos-methyl, parathion-methyl, glufosinate-methyl, ethoprophos-p, triazophos, pyrazofos-methyl, fenthion-methyl, pirimiphos-methyl, fenthion-methyl, phoxim-methyl, quinalphos, phofos-methyl, terbufos, fenthion, phos-ethyl, ethiophos, ethylbromophos, ethephon, fenamiphos, fenthion, thiochloride, fosthiazate, ethion, isoprothion, isoprothiolane, ethoprophos-methyl, Terbufos, gossypos, fenitrothion, phosphorus of vegetables and fruits, coumaphos, fenitrothion, methoprophos, pyridaphethione, fluthion, prothiochlor and systemic phos.
9. The use of the test paper for detecting organophosphorus pesticide as claimed in claim 8 is characterized in that: the detection process is as follows,
when a sample to be detected is detected, firstly, a solution of the sample to be detected is dripped onto a water passing area of upper-layer test paper, a water absorbing material is padded below the upper-layer test paper, so that the solution is continuously concentrated and enriched in the process of flowing through a hydrophobic adsorption material, and then the water absorbing material below filter paper is removed;
sequentially attaching the upper layer, the middle layer and the lower layer together to form a three-layer laminated composite structure, and sequentially and correspondingly laminating the water passing areas of the upper layer, the middle layer and the lower layer of test paper from top to bottom; then, dropwise adding a strong base solution on the water passing area of the upper layer test paper, after organic phosphorus is hydrolyzed by the strong base solution, eluting from the silica gel adsorption material, entering the buffer salt area of the middle layer, adjusting the pH value, permeating into the lower layer, performing redox reaction with the oxidant of the lower layer, generating color change after the oxidant is reduced, stripping the filter paper of the lower layer, and realizing qualitative and quantitative analysis on the organic phosphorus by judging the color change intensity of the oxidant;
if the organophosphorus pesticide exists in the test paper, the color of the test paper changes from red to light red to yellow along with the increase of the content of the organophosphorus pesticide; if the organophosphorus pesticide exists in the test paper immobilized with the ferric chloride, the color of the test paper changes from yellow to light yellow to white along with the increase of the content of the organophosphorus pesticide.
10. The use of the test paper for detecting organophosphorus pesticide as claimed in claim 9, is characterized in that: the water absorbing material is one or more than two of absorbent cotton, high molecular water absorbing polymer and filter paper;
the alkali solution is 0.5-1.0M of one or more of sodium hydroxide, potassium hydroxide, sodium ethoxide and ammonium hydroxide, and the using amount is 50-100 mu L.
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0353501A2 (en) * | 1988-07-30 | 1990-02-07 | Roche Diagnostics GmbH | Test strip for the analytical determination of a substance in a liquid sample |
| CN201773068U (en) * | 2010-03-12 | 2011-03-23 | 韩少春 | Multivariate test paper capable of testing pesticide residues of fruits and vegetables |
| CN105021596A (en) * | 2014-04-18 | 2015-11-04 | 曾嵘斌 | Concentration gradient based dry chemical test strip with multiple layers of films |
| CN106324243A (en) * | 2016-08-23 | 2017-01-11 | 广东志道医药科技有限公司 | Colloidal gold immunochromatography test strip and preparing and use method thereof |
| CN108132247A (en) * | 2016-12-01 | 2018-06-08 | 中国科学院大连化学物理研究所 | A kind of ferrous ion inspects paper and its preparation method and application soon |
-
2019
- 2019-03-25 CN CN201910227758.1A patent/CN109975281B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0353501A2 (en) * | 1988-07-30 | 1990-02-07 | Roche Diagnostics GmbH | Test strip for the analytical determination of a substance in a liquid sample |
| CN201773068U (en) * | 2010-03-12 | 2011-03-23 | 韩少春 | Multivariate test paper capable of testing pesticide residues of fruits and vegetables |
| CN105021596A (en) * | 2014-04-18 | 2015-11-04 | 曾嵘斌 | Concentration gradient based dry chemical test strip with multiple layers of films |
| CN106324243A (en) * | 2016-08-23 | 2017-01-11 | 广东志道医药科技有限公司 | Colloidal gold immunochromatography test strip and preparing and use method thereof |
| CN108132247A (en) * | 2016-12-01 | 2018-06-08 | 中国科学院大连化学物理研究所 | A kind of ferrous ion inspects paper and its preparation method and application soon |
Non-Patent Citations (2)
| Title |
|---|
| 中药材中有机磷农药荧光试纸条的开发;秦斌，王炳志，闫研，马红圳，杨星星;《中国现代中药》;20180416;全文 * |
| 酶促反应试纸条快速检测有机磷农药;丁国兴，王群，宋树强，张凯，冯振月;《中国法医学杂志》;20060830;全文 * |
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