CN101900684A - Test paper for quickly detecting urea in liquid milk and preparation method thereof - Google Patents
Test paper for quickly detecting urea in liquid milk and preparation method thereof Download PDFInfo
- Publication number
- CN101900684A CN101900684A CN2009102360250A CN200910236025A CN101900684A CN 101900684 A CN101900684 A CN 101900684A CN 2009102360250 A CN2009102360250 A CN 2009102360250A CN 200910236025 A CN200910236025 A CN 200910236025A CN 101900684 A CN101900684 A CN 101900684A
- Authority
- CN
- China
- Prior art keywords
- color
- colorimetric card
- urea
- indicator paper
- test paper
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Abstract
The invention discloses a test paper for quickly detecting urea in liquid milk and a preparation method thereof, and belongs to the field of chemical detection. The test paper consists of a detection substrate and a detection test paper. The test paper adopts the detection principle that: paradime thylaminobenzaldehyde is reacted with the urea to generate paradime thylaminobenzaldehyde urea under an acid condition, and the product is a lemon yellow compound. The method for quickly detecting the urea in the liquid milk has the advantages of quickness, sensitivity, simple and convenient operation and low cost, does not need a professional to operate, is convenient for common people to use at home, and also can be used for quick detection of industry and commerce, food safety and markets.
Description
Technical field
The present invention relates to a kind of fast, sensitive, detect the test paper and preparation method thereof of urea in the liquid milk easily, belong to field of chemical detection.
Background technology
After the melamine incident, the vibration of dairy products industry is very big, and urea detects and also more and more is much accounted of.Urea originally is the product of protein metabolism, is present on a small quantity in the mammiferous milk.But indivedual unprincipled fellows are for playing one's own game, will be as the most general a kind of nitrogenous fertilizer urea, sneak in the milk improving its nitrogen content, grievous injury eater, particularly infant healthy.
Urea be a kind of be the crystal of colorless and odorless, soluble in water and liquid milk mixes in the milk the not influence of color to milk, can increase the concentration of milk, sense organ and mouthfeel do not have much variations.It is the first-selected material that the dairy farmer mingles.Before the melamine incident, fresh milk purchase mode is prolonged with the past original method always, promptly with density, sense organ, acidity as acquisition criteria, some illegal dairy farmer mixes the urea bought easily on the market to increase milk density in milk, so that to adulteration, reach the purpose of unlawful profit-making, the business and consumer works the mischief to the milk purchase.Adulteration, to mix urea bigger to milk density influence, whenever mixes 5% water, and milk density will descend and 1 spend, and along with the increase of watering quantity, the density of milk descends thereupon.Mix urea in the milk milk density is increased, mix 0.5% urea,, mix 1% urea, can make density increase by 1 degree, mix 1.5% urea, can make milk density increase the 3-4 degree the almost not influence of density of milk.Promptly add 5% water in former milk, mix 1% urea simultaneously, milk density is not reduced and reach acquisition criteria, add more water in milk, mix a certain proportion of urea simultaneously, it is constant even improve its density to keep milk density.
The mensuration of urea concentration generally has four kinds of methods.The one, traditional method, i.e. spectrophotometer method.In the liquid milk sample, add the particular agent urase, the urea decomposition in the sample generated ammonia, ammonia and coloring agent reaction generation blue material, by the spectrochrome intensity of solution medium blue can working sample in the concentration of urea.The 2nd, form a kind of pink material with the urea molecule in a kind of dye mediator diacetyl monoxime and the sample, generating urea concentration in pink intensity and the solution has certain relevant.The 3rd, oil meter urase pH method generates orange colour to bottle-green continuous look by urea reaction, can measure the urea of variable concentrations.The 4th kind of method is to use infrared technique.Infrared technique has been used to measure butterfat percnetage and protein ratio at present.Some organic molecules all can produce Infrared Reflective Spectra by heating, are specific for this spectrum of different molecular, and the reflectance spectrum intensity that produces is relevant with the concentration of molecule, utilize this feature can working sample in the concentration of urea.
The various analytical instrument that urea in the special detection liquid milk is arranged in the market, the large-scale instrument cost is high and can only use in the laboratory, novel desk-top, hand-held analyzer device cost is higher, common people can not consume.Therefore, press for method and the technological means thereof of setting up urea in the fast detecting liquid milk on the market.
Summary of the invention
The invention discloses the method for urea content in a kind of tracer liquid, it is characterized in that, described method comprises: indicator paper block is inserted the liquid that detects, cause in the liquid urea with before this dipping and the dried medicament generation chromogenic reaction that is attached on the test paper, the color change reactions of test paper goes out contained content of urea in the liquid, color reaction district color with the colorimetric card control stripes of the known urea content numerical value of appendix, find on the colorimetric card and the identical colour band of this color reaction district color, reading its value corresponding from this color lump, is exactly the urea content numerical value in the described liquid.
Described method uses following reagent to make first kind of indicator paper block:
The hydrochloric acid of 0.5-5% parts by volume, the paradime thylaminobenzaldehyde of 1-10% parts by volume, and the spreading agent of 0.1-1% parts by volume, all the other are distilled water;
The making of described first kind of indicator paper block, use step are:
By the prescription of first kind of reagent order weighing reagent component one by one, and add in the entry one by one and dissolve, place the immersion liquid dish stand-by;
The chromatography filter paper that cuts was soaked in the middle of solution evenly, be suspended in the baking oven;
In baking oven with 60 ℃ of left and right sides dry filter papers 5 to 25 minutes, till drying;
The filter paper of handling well is sticked on the substrate, be cut into fritter;
Be sealed in and store indicator paper block in the 2-30 ℃ of dry environment, must not be put in storage in the refrigerator, must not make it to be subjected to the sunlight direct projection;
Get indicator paper block, immerse product to be measured or sample,, perhaps in the milk, and take out immediately as emulsion;
Horizontal positioned is up distinguished in test paper check, compared, in 30 seconds, read the sxemiquantitative assay with the color of colorimetric card;
Test paper color and first kind of colorimetric card are compared, and the color range value corresponding identical with the colorimetric card color is the detected value of this sample; Between two color ranges, then get both intermediate values as the color of test paper;
The preparation method of described first kind of colorimetric card is:
Prepare above-mentioned first kind of reagent in advance, and then preparation and store above-mentioned indicator paper block;
Dispose the milk of known urea content, form the standard milk sample series that contains urea, the urea concentration in this series is distributed in predetermined known range;
Above-mentioned indicator paper block is inserted respectively in the different samples in the above-mentioned series, obtain the variable color indicator paper block, with the color lump of high precision camera color change interval;
With image processing software the color lump in each photo is handled, numerical value according to known urea content is arranged from small to large, and the pairing color lump of this numerical value series is arranged, and obtains colour band, at each color lump next door, the known urea content numerical value that mark is corresponding;
Colour print output gained colour band obtains described colorimetric card;
Described colorimetric card is carried out plastic packaging, load the coating or the protective film that prevent that described colorimetric card is contaminated or damage.
Except using first kind of indicator paper block, method of the present invention also can and be used second kind of indicator paper block according to the following steps preparation:
Add concentrated sulphuric acid 48ml, 85% phosphoric acid 68ml in 100ml distilled water, shake up, 15～30 degrees centigrade add thiosemicarbazides 52mg and cadmium sulfate 3g down, and the dissolving back to 1L, obtains first solution with distilled water diluting.Get the 180mmol/L Diacetylmonoxime solution of 19g and put into distilled water and be diluted to 1L, obtain second solution.Mix above-mentioned first, second solution, about 4 degrees centigrade, placed 3～15 minutes, add the spreading agent of 0.1-0.3% parts by volume then.After mentioned reagent configuration is finished 4 degrees centigrade of preservations;
The chromatography filter paper that cuts was soaked from solution evenly, about 4 degrees centigrade, dried; The filter paper of handling well is sticked on the substrate, be cut into fritter, form second kind of indicator paper block;
Be sealed in and store indicator paper block in 4 ℃ of dry environments;
The using method of described second kind of indicator paper block is:
Get second kind of indicator paper block, immerse in the testing liquid, and take out immediately;
Horizontal positioned is up distinguished in test paper check, compared, in 30 seconds, read the sxemiquantitative assay with the color of colorimetric card;
Test paper color and second kind of colorimetric card are compared, and the color range value corresponding identical with the colorimetric card color is the detected value of this sample; Between two color ranges, then get both intermediate values as the color of test paper;
The preparation method of described second kind of colorimetric card is:
Prepare above-mentioned second kind of reagent in advance, and then preparation and store above-mentioned indicator paper block;
Dispose the milk of known urea content, form the standard milk sample series that contains urea, the urea concentration in this series is distributed in predetermined known range;
Above-mentioned indicator paper block is inserted respectively in the different samples in the above-mentioned series, obtain the variable color indicator paper block, with the color lump of high precision camera color change interval;
With image processing software the color lump in each photo is handled, numerical value according to known urea content is arranged from small to large, and the pairing color lump of this numerical value series is arranged, and obtains colour band, at each color lump next door, the known urea content numerical value that mark is corresponding;
Colour print output gained colour band obtains described colorimetric card;
Described colorimetric card is carried out plastic packaging, load the coating or the protective film that prevent that described colorimetric card is contaminated or damage.
The invention also discloses the compound test paper of double end, it is characterized in that, described indicator paper block comprises an operational zone 101, one end is fixed with first indicator paper block 102, the other end is fixed with second indicator paper block 103, on operational zone 101, near the zone of first indicator paper block 102, second indicator paper block 103, mark has the title or the numbering of first colorimetric card, second colorimetric card respectively;
During urea content, 102 ends with described test paper record urea content numerical value A earlier, record another numerical value B with 103 ends then in the tracer liquid.Account for 97% weight according to A, B accounts for 94% weight, tries to achieve the higher weighted average increment C of precision.C is the urea content value of detected object;
The measured value step of obtaining numerical value A, B with first indicator paper block 102, second indicator paper block 103 is: getting an amount of sample in the clean dried container, is standard can not have the test paper test block; The test paper test block is all immersed in the testing sample, and taken out immediately; Horizontal positioned is up distinguished in test paper check, compared, in 30 seconds, read the sxemiquantitative assay with the color of colorimetric card; Colorimetric card on test paper color and the Packaging Bottle is compared, and the color range value corresponding identical with the colorimetric card color is the detected value of this sample; Between two color ranges, then get both intermediate values as the color of test paper.
Particularly, the invention discloses the method for quick of urea in a kind of simple and easy to do liquid milk, invented the relevant detection test paper, can detect urea in the various liquid milks of market sale easily and quickly, read the sxemiquantitative assay at 30 seconds meat.Colorimetric card on test paper color and the Packaging Bottle is compared, and the color range value corresponding identical with the colorimetric card color is the detected value of this sample.
The scope of application of the present invention: the half-quantitative detection of urea in the liquid milk, sensing range: 0.1-10.0g/kg; Detect principle: utilize the medicament generation chromogenic reaction on urea and the test paper, the color change reactions of test paper goes out contained content of urea in the food.
Method of operating: getting an amount of sample in the clean dried container, is standard can not have the test paper test block; The test paper test block is all immersed in the testing sample, and taken out immediately; Horizontal positioned is up distinguished in test paper check, compared, in 30 seconds, read the sxemiquantitative assay with the color of colorimetric card.
The result judges: colorimetric card on test paper color and the Packaging Bottle is compared, and the color range value corresponding identical with the colorimetric card color is the detected value of this sample; Between two color ranges, then get both intermediate values as the color of test paper.
The present invention selects for use two group reagents to realize its goal of the invention, and and then produce the double end test paper that carries out composite test, proposed to carry out composite test and calculated, obtain the compound detection computing method of high precision urea content:
The reaction principle of first kind of reagent is: paradime thylaminobenzaldehyde generates the paradime thylaminobenzaldehyde urea with urea reaction under acid condition, product is lemon yellow compound (hereinafter also being called for short electrochromic compound), sensitivity can reach 0.1g/kg, the shade of described lemon yellow compound is directly proportional with urea content, the specimen that urea content is different, the corresponding different lemon yellow of the depth that shows on test paper, content is big more, and color is dark more.The color range value corresponding identical with the colorimetric card color is the urea content detected value of specific sample.Paradime thylaminobenzaldehyde is measured in the solution of urea content, and higher acidity can improve the absorbance of chromogenic reaction, and and then influence optical density; Inventor's repetition test is found, reagent comprises 0.5% above hydrochloric acid, but preferred 4% above hydrochloric acid stabilizing solution absorbance, and then the optical density of stable electrochromic compound, more hydrochloric acid then can obviously not improve absorbance and optical density again, so content of hydrochloric acid is the highest may be selected to be 5%.Reagent of the present invention has also added spreading agent.But its homogeneous dispersion solid particle prevents solid particles sediment and cohesion, makes the detection emulsion be homogeneous phase and distributes.
For this reason, first kind of used reagent of the present invention comprises: the hydrochloric acid of 0.5-5% parts by volume, and the paradime thylaminobenzaldehyde of 1-10% parts by volume, and the spreading agent of 0.1-1% parts by volume, all the other are distilled water.This reagent is used to make first kind of indicator paper block.
The making of this first kind of indicator paper block, use step are:
A. by the prescription of first kind of reagent order weighing reagent component one by one, and add in the entry one by one and dissolve, place the immersion liquid dish stand-by;
B. the chromatography filter paper that will cut was soaked in the middle of solution evenly, was suspended in the baking oven;
C. in baking oven with 60 ℃ of left and right sides dry filter papers 5 to 25 minutes, till drying;
D. the filter paper of handling well is sticked on the substrate, be cut into fritter, form indicator paper block, the stick form test paper piece of for example long 8cm, wide 1cm;
E. be sealed in and store indicator paper block in the 2-30 ℃ of dry environment, must not be put in storage in the refrigerator, must not make it to be subjected to the sunlight direct projection;
F. get indicator paper block, immerse product to be measured or sample,, perhaps in the milk, and take out immediately as emulsion;
G. test paper check is distinguished horizontal positioned up, compared, in 30 seconds, read the sxemiquantitative assay with the color of colorimetric card (hereinafter claiming first kind of colorimetric card);
H. colorimetric card on test paper color and the Packaging Bottle is compared, the color range value corresponding identical with the colorimetric card color is the detected value of this sample; Between two color ranges, then get both intermediate values as the color of test paper.Through measuring and calculating, the error of this method is about 3%.
The preparation method of described first kind of colorimetric card is:
A. prepare above-mentioned first kind of reagent in advance, and then preparation and store above-mentioned indicator paper block;
B. dispose the milk of known urea content, form the standard milk sample series that contains urea, the urea concentration in this series is distributed in predetermined known range;
C. above-mentioned indicator paper block is inserted respectively in the different samples in the above-mentioned series, obtain the variable color indicator paper block, with the color lump of high precision camera color change interval;
D. with image processing software the color lump in each photo is handled, numerical value according to known urea content is arranged from small to large, and the pairing color lump of this numerical value series is arranged, and obtains colour band, at each color lump next door, the known urea content numerical value that mark is corresponding;
E. colour print output gained colour band obtains described colorimetric card;
F. described colorimetric card is carried out plastic packaging, load the coating or the protective film that prevent that described colorimetric card is contaminated or damage.
With the indicator paper block of above-mentioned first kind of reagent of the present invention, correspondence, and colorimetric card, arbitrary emulsion, milk can be measured, perhaps the urea content in other liquid.
In order to improve measuring accuracy, the invention also discloses second kind of reagent of test paper colorimetric method for determining urea content, and then use the double end test paper, and the compound detection computing method.
The reaction principle of second kind of reagent is: in the strong acid solution that comprises thiosemicarbazide, cadmium ion, diacetyl and urea can be condensed into redness 4,5-dimethyl-2-oxygen imidazolium compounds, and the shade of this compound is directly proportional with urea content, color is dark more, and content is big more.As a same reason, reagent of the present invention has also added spreading agent.But its homogeneous dispersion solid particle prevents solid particles sediment and cohesion, makes the detection emulsion be homogeneous phase and distributes.
For this reason, the present invention has disposed second kind of reagent: add concentrated sulphuric acid 48ml, 85% phosphoric acid 68ml in 100ml distilled water, shake up, 15～30 degrees centigrade add thiosemicarbazides 52mg and cadmium sulfate 3g down, and the dissolving back to 1L, obtains first solution with distilled water diluting.Get the 180mmol/L Diacetylmonoxime solution of 19g and put into distilled water and be diluted to 1L, obtain second solution.Mix above-mentioned first, second solution, about 4 degrees centigrade, placed 3～15 minutes, add the spreading agent of 0.1-0.3% parts by volume then.After finishing, the mentioned reagent configuration, is used to make second kind of indicator paper block 4 degrees centigrade of preservations.
The making of this second kind of indicator paper block, use step are:
A. press the prescription order weighing reagent component one by one of second kind of reagent, and dispose stand-by;
B. the chromatography filter paper that will cut was soaked from solution evenly, dried about 4 degrees centigrade;
C. the filter paper of handling well is sticked on the substrate, be cut into fritter, form second kind of indicator paper block, the stick form test paper piece of for example long 8cm, wide 1cm;
D. be sealed in and store indicator paper block in 4 ℃ of dry environments;
E. get second kind of indicator paper block, immerse product to be measured or sample,, perhaps in the milk, and take out immediately as emulsion;
F. test paper check is distinguished horizontal positioned up, compared, in 30 seconds, read the sxemiquantitative assay with the color of colorimetric card (hereinafter claiming first kind of colorimetric card);
G. colorimetric card on test paper color and the Packaging Bottle is compared, the color range value corresponding identical with the colorimetric card color is the detected value of this sample; Between two color ranges, then get both intermediate values as the color of test paper.Through measuring and calculating, the error of this method is about 6%.
The preparation method of described second kind of colorimetric card is:
A. prepare above-mentioned second kind of reagent in advance, and then preparation and store above-mentioned indicator paper block;
B. dispose the milk of known urea content, form the standard milk sample series that contains urea, the urea concentration in this series is distributed in predetermined known range;
C. above-mentioned indicator paper block is inserted respectively in the different samples in the above-mentioned series, obtain the variable color indicator paper block, with the color lump of high precision camera color change interval;
D. with image processing software the color lump in each photo is handled, numerical value according to known urea content is arranged from small to large, and the pairing color lump of this numerical value series is arranged, and obtains colour band, at each color lump next door, the known urea content numerical value that mark is corresponding;
E. colour print output gained colour band obtains described colorimetric card;
F. described colorimetric card is carried out plastic packaging, load the coating or the protective film that prevent that described colorimetric card is contaminated or damage.
With the indicator paper block of above-mentioned second kind of reagent of the present invention, correspondence, and colorimetric card, arbitrary emulsion, milk can be measured, perhaps the urea content in other liquid.
In order to improve accuracy of detection, and then use the compound test paper of double end, and the compound detection computing method, the present invention is fixed on first indicator paper block, second indicator paper block on the operational zone 101.Forming an end is first indicator paper block 102, and the other end is the double end test strips of second indicator paper block 103.On the operational zone 101, near the zone of first indicator paper block 102, second indicator paper block 103, mark has the title or the numbering of first colorimetric card, second colorimetric card respectively.
The time marquis of urea content in detecting milk or other liquid can be earlier records urea content numerical value A with 102 ends of described compound test paper, records another numerical value B with 103 ends then.Account for 97% weight according to A, B accounts for 94% weight, tries to achieve the higher weighted average increment C of precision.C is exactly the urea content of detected object.
The present invention is used for the fast detecting of liquid milk urea, this method has fast, sensitive, easy and simple to handle, advantage that cost is low, need not professional's operation, be convenient to the common people and use voluntarily in the family, also can be used for the fast detecting in industrial and commercial law enforcement, food security, market.
Description of drawings
Fig. 1 is the indicator paper block structural representation
Embodiment
Embodiment 1
First kind of indicator paper block of the present invention made flow process: by the prescription order of first kind of reagent weighing reagent one by one, and dissolving one by one, place the immersion liquid dish stand-by; With the filter paper (model: 3MM) in the middle of solution, soaked evenly, and be suspended in the baking oven, dry 25min under 60 ℃ that cuts.The filter paper of handling well is sticked on the substrate, and the strip of cutting growth 8cm, wide 1cm is sealed in the 2-30 ℃ of dry environment and stores, and must not be put in the refrigerator, must not be subjected to the sunlight direct projection.
Embodiment 2
Buying does not contain urea from the liquid milk sample in supermarket through instrument detecting.Getting an amount of sample in the clean dried container, is standard can not have the test paper test block; The test paper test block is all immersed in the testing sample, and taken out immediately; With test paper reagent piece horizontal positioned and relatively up, in 30 seconds, read the sxemiquantitative assay with colorimetric card.The result judges that urea content is 0.
Add the urea of 0.5g/kg concentration in not urea-containing liquid milk sample, detect by above-mentioned steps, the numerical value that the result judges conforms to actual addition.
Embodiment 3
10 parts of liquid milk samples that market is sold detect with the urea quick detection test paper, and the result judges that wherein 9 parts is normal liquid milk, and 1 part has been added urea.Above-mentioned 10 duplicate samples are all verified through the mensuration of instrument.
Embodiment 4
Present embodiment discloses the compound test paper of double end, and the compound detection computing method.
First kind of used reagent of present embodiment comprises: the hydrochloric acid of 5% parts by volume, and the paradime thylaminobenzaldehyde of 10% parts by volume, and the spreading agent of 1% parts by volume, all the other are distilled water.This reagent is used to make first kind of indicator paper block.
The making step of this first kind of indicator paper block is: by the prescription of first kind of reagent order weighing reagent component one by one, and add in the entry one by one and dissolve, place the immersion liquid dish stand-by; The chromatography filter paper that cuts was soaked in the middle of solution evenly, be suspended in the baking oven; In baking oven,, make it dry with 60 ℃ of dry filter papers 15 minutes; The filter paper of handling well is sticked on the substrate stick form test paper piece of cutting growth 4cm, wide 1cm; Be sealed in and store indicator paper block in 10 ℃ of dry environments.
The preparation method of first kind of colorimetric card is: the milk that disposes known urea content, formation contains the standard milk sample series of urea, urea concentration in this series is distributed in predetermined known range, this numerical value series is 0.1,0.5,1,1.5,2,2.5,3,3.5,4,4.5,5,5.5,6,6.5,7,7.5,8,8.5,9,9.5,10.0g/kg, and promptly per kilogram milk contains the urea of above-mentioned numerical value g; Above-mentioned indicator paper block is inserted respectively in the different samples in the above-mentioned series, obtain the variable color indicator paper block, with the color lump of high precision camera color change interval; With image processing software the color lump in each photo is handled, numerical value according to known urea content is arranged from small to large, and the pairing color lump of this numerical value series is arranged, and obtains colour band, at each color lump next door, the known urea content numerical value that mark is corresponding; Colour print output gained colour band obtains described colorimetric card; Described colorimetric card is carried out plastic packaging, load the coating or the protective film that prevent that described colorimetric card is contaminated or damage.
Present embodiment has disposed second kind of reagent: add concentrated sulphuric acid 48ml, 85% phosphoric acid 68ml in 100ml distilled water, shake up, 15 degrees centigrade add thiosemicarbazides 52mg and cadmium sulfate 3g down, and the dissolving back to 1L, obtains first solution with distilled water diluting.Get the 180mmol/L Diacetylmonoxime solution of 19g and put into distilled water and be diluted to 1L, obtain second solution.Mix above-mentioned first, second solution, about 4 degrees centigrade, placed 3～15 minutes, add the spreading agent of 0.1-0.3% parts by volume then.After finishing, the mentioned reagent configuration, is used to make second kind of indicator paper block 4 degrees centigrade of preservations.
The making step of this second kind of indicator paper block is: by the prescription order weighing reagent component one by one of second kind of reagent, and dispose stand-by; The chromatography filter paper that cuts was soaked from solution evenly, about 4 degrees centigrade, dried; The filter paper of handling well is sticked on the substrate stick form test paper piece of cutting growth 4cm, wide 1cm; Be sealed in and store indicator paper block in 4 ℃ of dry environments.
The preparation method of second kind of colorimetric card is: prepare above-mentioned second kind of reagent in advance, and then preparation and store above-mentioned indicator paper block; Dispose the milk of known urea content, formation contains the standard milk sample series of urea, urea concentration in this series is distributed in predetermined known range, this numerical value series is 0.1,0.5,1,1.5,2,2.5,3,3.5,4,4.5,5,5.5,6,6.5,7,7.5,8,8.5,9,9.5,10.0g/kg, and promptly per kilogram milk contains the urea of above-mentioned numerical value g; Above-mentioned indicator paper block is inserted respectively in the different samples in the above-mentioned series, obtain the variable color indicator paper block, with the color lump of high precision camera color change interval; With image processing software the color lump in each photo is handled, numerical value according to known urea content is arranged from small to large, and the pairing color lump of this numerical value series is arranged, and obtains colour band, at each color lump next door, the known urea content numerical value that mark is corresponding; Colour print output gained colour band obtains described colorimetric card; Described colorimetric card is carried out plastic packaging, load the coating or the protective film that prevent that described colorimetric card is contaminated or damage.
Present embodiment is fixed on first indicator paper block, second indicator paper block on the operational zone 101.Forming an end is first indicator paper block 102, and the other end is the double end test strips of second indicator paper block 103.On the operational zone 101, near the zone of first indicator paper block 102, second indicator paper block 103, mark has the title of first colorimetric card, second colorimetric card respectively.
To milk to be measured, record urea content numerical value A with 102 ends of described compound test paper, record another numerical value B with 103 ends then.Account for 97% weight according to A, B accounts for 94% weight, tries to achieve the higher weighted average increment C of precision.C is exactly the urea content of detected object.
The measured value step of obtaining numerical value A, B with first indicator paper block 102, second indicator paper block 103 is: getting an amount of sample in the clean dried container, is standard can not have the test paper test block; The test paper test block is all immersed in the testing sample, and taken out immediately; Horizontal positioned is up distinguished in test paper check, compared, in 30 seconds, read the sxemiquantitative assay with the color of colorimetric card.
The result judges: colorimetric card on test paper color and the Packaging Bottle is compared, and the color range value corresponding identical with the colorimetric card color is the detected value of this sample; Between two color ranges, then get both intermediate values as the color of test paper.
Claims (5)
1. the method for urea content in the tracer liquid, it is characterized in that, described method comprises: indicator paper block is inserted the liquid that detects, cause in the liquid urea with before this dipping and the dried medicament generation chromogenic reaction that is attached on the test paper, the color change reactions of test paper goes out contained content of urea in the liquid, color reaction district color with the colorimetric card control stripes of the known urea content numerical value of appendix, find on the colorimetric card and the identical colour band of this color reaction district color, reading its value corresponding from this color lump, is exactly the urea content numerical value in the described liquid.
2. the method for urea content is characterized in that in the tracer liquid according to claim 1, and described method uses following reagent to make first kind of indicator paper block:
The hydrochloric acid of 0.5-5% parts by volume, the paradime thylaminobenzaldehyde of 1-10% parts by volume, and the spreading agent of 0.1-1% parts by volume, all the other are distilled water;
The making of described first kind of indicator paper block, use step are:
By the prescription of first kind of reagent order weighing reagent component one by one, and add in the entry one by one and dissolve, place the immersion liquid dish stand-by;
The chromatography filter paper that cuts was soaked in the middle of solution evenly, be suspended in the baking oven;
In baking oven with 60 ℃ of left and right sides dry filter papers 5 to 25 minutes, till drying;
The filter paper of handling well is sticked on the substrate, be cut into fritter;
Be sealed in and store indicator paper block in the 2-30 ℃ of dry environment, must not be put in storage in the refrigerator, must not make it to be subjected to the sunlight direct projection;
Get indicator paper block, immerse product to be measured or sample,, perhaps in the milk, and take out immediately as emulsion;
Horizontal positioned is up distinguished in test paper check, compared, in 30 seconds, read the sxemiquantitative assay with the color of colorimetric card;
Test paper color and first kind of colorimetric card are compared, and the color range value corresponding identical with the colorimetric card color is the detected value of this sample; Between two color ranges, then get both intermediate values as the color of test paper;
The preparation method of described first kind of colorimetric card is:
Prepare above-mentioned first kind of reagent in advance, and then preparation and store above-mentioned indicator paper block;
Dispose the milk of known urea content, form the standard milk sample series that contains urea, the urea concentration in this series is distributed in predetermined known range;
Above-mentioned indicator paper block is inserted respectively in the different samples in the above-mentioned series, obtain the variable color indicator paper block, with the color lump of high precision camera color change interval;
With image processing software the color lump in each photo is handled, numerical value according to known urea content is arranged from small to large, and the pairing color lump of this numerical value series is arranged, and obtains colour band, at each color lump next door, the known urea content numerical value that mark is corresponding;
Colour print output gained colour band obtains described colorimetric card;
Described colorimetric card is carried out plastic packaging, load the coating or the protective film that prevent that described colorimetric card is contaminated or damage.
3. the method for urea content is characterized in that in the tracer liquid according to claim 1, and described method prepares indicator paper block according to following steps:
Add concentrated sulphuric acid 48ml, 85% phosphoric acid 68ml in 100ml distilled water, shake up, 15～30 degrees centigrade add thiosemicarbazides 52mg and cadmium sulfate 3g down, and the dissolving back to 1L, obtains first solution with distilled water diluting.Get the 180mmol/L Diacetylmonoxime solution of 19g and put into distilled water and be diluted to 1L, obtain second solution.Mix above-mentioned first, second solution, about 4 degrees centigrade, placed 3～15 minutes, add the spreading agent of 0.1-0.3% parts by volume then.After mentioned reagent configuration is finished 4 degrees centigrade of preservations;
The chromatography filter paper that cuts was soaked from solution evenly, about 4 degrees centigrade, dried; The filter paper of handling well is sticked on the substrate, be cut into fritter, form second kind of indicator paper block;
Be sealed in and store indicator paper block in 4 ℃ of dry environments;
The using method of described second kind of indicator paper block is:
Get second kind of indicator paper block, immerse in the testing liquid, and take out immediately;
Horizontal positioned is up distinguished in test paper check, compared, in 30 seconds, read the sxemiquantitative assay with the color of colorimetric card;
Test paper color and second kind of colorimetric card are compared, and the color range value corresponding identical with the colorimetric card color is the detected value of this sample; Between two color ranges, then get both intermediate values as the color of test paper;
The preparation method of described second kind of colorimetric card is:
Prepare above-mentioned second kind of reagent in advance, and then preparation and store above-mentioned indicator paper block;
Dispose the milk of known urea content, form the standard milk sample series that contains urea, the urea concentration in this series is distributed in predetermined known range;
Above-mentioned indicator paper block is inserted respectively in the different samples in the above-mentioned series, obtain the variable color indicator paper block, with the color lump of high precision camera color change interval;
With image processing software the color lump in each photo is handled, numerical value according to known urea content is arranged from small to large, and the pairing color lump of this numerical value series is arranged, and obtains colour band, at each color lump next door, the known urea content numerical value that mark is corresponding;
Colour print output gained colour band obtains described colorimetric card;
Described colorimetric card is carried out plastic packaging, load the coating or the protective film that prevent that described colorimetric card is contaminated or damage.
4. the method for urea content in the tracer liquid according to claim 1, it is characterized in that, described indicator paper block comprises an operational zone (101), one end is fixed with first indicator paper block (102), the other end is fixed with second indicator paper block (103), on operational zone (101), near the zone of first indicator paper block (102), second indicator paper block (103), mark has the title or the numbering of first colorimetric card, second colorimetric card respectively;
During urea content, (102) end with described test paper records urea content numerical value A earlier, uses (103) to hold then and records another numerical value B in the tracer liquid.Account for 97% weight according to A, B accounts for 94% weight, tries to achieve the higher weighted average increment C of precision.C is the urea content value of detected object;
The measured value step of obtaining numerical value A, B with first indicator paper block (102), second indicator paper block (103) is: getting an amount of sample in the clean dried container, is standard can not have the test paper test block; The test paper test block is all immersed in the testing sample, and taken out immediately; Horizontal positioned is up distinguished in test paper check, compared, in 30 seconds, read the sxemiquantitative assay with the color of colorimetric card; Colorimetric card on test paper color and the Packaging Bottle is compared, and the color range value corresponding identical with the colorimetric card color is the detected value of this sample; Between two color ranges, then get both intermediate values as the color of test paper.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2009102360250A CN101900684A (en) | 2009-10-16 | 2009-10-16 | Test paper for quickly detecting urea in liquid milk and preparation method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2009102360250A CN101900684A (en) | 2009-10-16 | 2009-10-16 | Test paper for quickly detecting urea in liquid milk and preparation method thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN101900684A true CN101900684A (en) | 2010-12-01 |
Family
ID=43226403
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2009102360250A Pending CN101900684A (en) | 2009-10-16 | 2009-10-16 | Test paper for quickly detecting urea in liquid milk and preparation method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN101900684A (en) |
Cited By (18)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102590201A (en) * | 2012-02-17 | 2012-07-18 | 中国原子能科学研究院 | Method for analyzing amino hydroxyurea in uranium-plutonium separated plutonium solution |
| CN102788863A (en) * | 2012-05-18 | 2012-11-21 | 贵州神奇药业股份有限公司 | Detection method of compound preparation containing compound Zingiber corallinum Hance solution and urea miconazole ointment |
| CN104251860A (en) * | 2013-06-28 | 2014-12-31 | 成都谱视科技有限公司 | Food safety testing analyzer based on intelligent terminal and testing method |
| CN104497467A (en) * | 2014-09-30 | 2015-04-08 | 衢州市柯城富星制胶厂 | Styryl composite material |
| CN105105761A (en) * | 2015-09-16 | 2015-12-02 | 福建师范大学 | Chemical appearing method for potential finger prints |
| CN106443020A (en) * | 2016-09-09 | 2017-02-22 | 江苏迈特博生物科技有限公司 | Test paper for detecting phenyl ethylamine as well as preparing method and method of application thereof |
| CN106546583A (en) * | 2016-11-09 | 2017-03-29 | 无锡艾科瑞思产品设计与研究有限公司 | A kind of tripolycyanamide Test paper |
| CN106706620A (en) * | 2016-12-15 | 2017-05-24 | 厦门海荭兴仪器股份有限公司 | Rapid benzoyl peroxide detection method and kit |
| CN107219328A (en) * | 2017-06-21 | 2017-09-29 | 合肥荣事达电子电器集团有限公司 | A kind of urine automatic Titration detection means |
| CN107703124A (en) * | 2016-08-08 | 2018-02-16 | 安恒环境科技（北京）股份有限公司 | Urea concentration detection method and urea concentration on-line monitoring equipment |
| CN107764811A (en) * | 2016-08-16 | 2018-03-06 | 中国石油化工股份有限公司 | A kind of method and its application of the processing method of urea liquid and measure urea concentration |
| CN109358051A (en) * | 2018-12-18 | 2019-02-19 | 沈阳理工大学 | Survey the chain alkyl trimethyl ammonium enhanced sensitivity mix reagent test paper and preparation method of ammonia in air |
| CN110470660A (en) * | 2019-07-30 | 2019-11-19 | 北京倍肯恒业科技发展股份有限公司 | The detection card component and method of thiocarbamide are remained in a kind of quick detection flour product |
| CN110470661A (en) * | 2019-07-30 | 2019-11-19 | 北京倍肯恒业科技发展股份有限公司 | The method and kit of thiocarbamide are remained in a kind of quick detection flour product |
| CN110687106A (en) * | 2019-10-14 | 2020-01-14 | 武汉大学 | Paper-based color-comparison type sensing array label and preparation method and application thereof |
| CN110793949A (en) * | 2019-11-12 | 2020-02-14 | 杭州百合科莱恩颜料有限公司 | Method for rapidly and semi-quantitatively determining concentration of residual aromatic amine in aromatic amine diazonium salt |
| CN112816462A (en) * | 2020-12-29 | 2021-05-18 | 居天联影科技(深圳)有限公司 | Animal milk quality analyzer |
| CN113106142A (en) * | 2021-04-15 | 2021-07-13 | 北京华益精点生物技术有限公司 | Reagent kit for semi-quantitative detection of urea in food and preparation method of test paper |
-
2009
- 2009-10-16 CN CN2009102360250A patent/CN101900684A/en active Pending
Cited By (24)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102590201B (en) * | 2012-02-17 | 2014-04-02 | 中国原子能科学研究院 | Method for analyzing amino hydroxyurea in uranium-plutonium separated plutonium solution |
| CN102590201A (en) * | 2012-02-17 | 2012-07-18 | 中国原子能科学研究院 | Method for analyzing amino hydroxyurea in uranium-plutonium separated plutonium solution |
| CN102788863A (en) * | 2012-05-18 | 2012-11-21 | 贵州神奇药业股份有限公司 | Detection method of compound preparation containing compound Zingiber corallinum Hance solution and urea miconazole ointment |
| CN102788863B (en) * | 2012-05-18 | 2014-04-23 | 贵州神奇药业股份有限公司 | Detection method of compound preparation containing compound Zingiber corallinum Hance solution and urea miconazole ointment |
| CN104251860A (en) * | 2013-06-28 | 2014-12-31 | 成都谱视科技有限公司 | Food safety testing analyzer based on intelligent terminal and testing method |
| CN104497467A (en) * | 2014-09-30 | 2015-04-08 | 衢州市柯城富星制胶厂 | Styryl composite material |
| CN105105761A (en) * | 2015-09-16 | 2015-12-02 | 福建师范大学 | Chemical appearing method for potential finger prints |
| CN107703124A (en) * | 2016-08-08 | 2018-02-16 | 安恒环境科技（北京）股份有限公司 | Urea concentration detection method and urea concentration on-line monitoring equipment |
| CN107764811A (en) * | 2016-08-16 | 2018-03-06 | 中国石油化工股份有限公司 | A kind of method and its application of the processing method of urea liquid and measure urea concentration |
| CN106443020A (en) * | 2016-09-09 | 2017-02-22 | 江苏迈特博生物科技有限公司 | Test paper for detecting phenyl ethylamine as well as preparing method and method of application thereof |
| CN106546583A (en) * | 2016-11-09 | 2017-03-29 | 无锡艾科瑞思产品设计与研究有限公司 | A kind of tripolycyanamide Test paper |
| CN106706620B (en) * | 2016-12-15 | 2019-05-03 | 厦门海荭兴仪器股份有限公司 | A kind of benzoyl peroxide rapid detection method |
| CN106706620A (en) * | 2016-12-15 | 2017-05-24 | 厦门海荭兴仪器股份有限公司 | Rapid benzoyl peroxide detection method and kit |
| CN107219328B (en) * | 2017-06-21 | 2023-04-07 | 合肥荣事达电子电器集团有限公司 | Automatic titration detection device for urine |
| CN107219328A (en) * | 2017-06-21 | 2017-09-29 | 合肥荣事达电子电器集团有限公司 | A kind of urine automatic Titration detection means |
| CN109358051A (en) * | 2018-12-18 | 2019-02-19 | 沈阳理工大学 | Survey the chain alkyl trimethyl ammonium enhanced sensitivity mix reagent test paper and preparation method of ammonia in air |
| CN110470660A (en) * | 2019-07-30 | 2019-11-19 | 北京倍肯恒业科技发展股份有限公司 | The detection card component and method of thiocarbamide are remained in a kind of quick detection flour product |
| CN110470660B (en) * | 2019-07-30 | 2021-02-05 | 北京倍肯恒业科技发展股份有限公司 | Detection card assembly and method for rapidly detecting residual thiourea in flour product |
| CN110470661A (en) * | 2019-07-30 | 2019-11-19 | 北京倍肯恒业科技发展股份有限公司 | The method and kit of thiocarbamide are remained in a kind of quick detection flour product |
| CN110687106A (en) * | 2019-10-14 | 2020-01-14 | 武汉大学 | Paper-based color-comparison type sensing array label and preparation method and application thereof |
| CN110687106B (en) * | 2019-10-14 | 2021-02-02 | 武汉大学 | Paper-based color-comparison type sensing array label and preparation method and application thereof |
| CN110793949A (en) * | 2019-11-12 | 2020-02-14 | 杭州百合科莱恩颜料有限公司 | Method for rapidly and semi-quantitatively determining concentration of residual aromatic amine in aromatic amine diazonium salt |
| CN112816462A (en) * | 2020-12-29 | 2021-05-18 | 居天联影科技(深圳)有限公司 | Animal milk quality analyzer |
| CN113106142A (en) * | 2021-04-15 | 2021-07-13 | 北京华益精点生物技术有限公司 | Reagent kit for semi-quantitative detection of urea in food and preparation method of test paper |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101900684A (en) | Test paper for quickly detecting urea in liquid milk and preparation method thereof | |
| Sinfield et al. | Evaluation of sensing technologies for on-the-go detection of macro-nutrients in cultivated soils | |
| Ensafi et al. | A highly selective optical sensor for catalytic determination of ultra-trace amounts of nitrite in water and foods based on brilliant cresyl blue as a sensing reagent | |
| Engel et al. | Printed sensor labels for colorimetric detection of ammonia, formaldehyde and hydrogen sulfide from the ambient air | |
| Bunkoed et al. | Sol–gel based sensor for selective formaldehyde determination | |
| CN101294896B (en) | Method for measuring cadmium content in smoke tipping paper | |
| CN101294898B (en) | Method for measuring chromium content in smoke tipping paper | |
| Ensafi et al. | Highly selective optical nitrite sensor for food analysis based on Lauth’s violet–triacetyl cellulose membrane film | |
| Tavčar et al. | Simple modification of Karl-Fischer titration method for determination of water content in colored samples | |
| Bhardwaj et al. | Visual & reversible sensing of cyanide in real samples by an effective ratiometric colorimetric probe & logic gate application | |
| Staneva et al. | Optical sensor for aliphatic amines based on the simultaneous colorimetric and fluorescence responses of smart textile | |
| Li et al. | Evaluating nitrite content changes in some Chinese home cooking with a newely-developed CDs diazotization spectrophotometry | |
| Xu et al. | Smartphone-based on-site detection of hydrogen peroxide in milk by using a portable ratiometric fluorescent probe | |
| Tan et al. | A novel optical ammonia sensor based on reflectance measurements for highly polluted and coloured water | |
| Růžička et al. | Flow injection analyzer for students, teaching and research: Spectrophotometric methods | |
| Barrales et al. | Indirect determination of ascorbic acid by solid-phase spectrophotometry | |
| CN106596490B (en) | The supermolecule sensor array and method of synchronous detection paraquat and diquat dibromide | |
| CN103512855A (en) | Reduced glutathione detection method | |
| Gibson et al. | On-site determination of formaldehyde: A low cost measurement device for museum environments | |
| ATE480773T1 (en) | METHOD FOR DETERMINING HEPARIN CONCENTRATION IN LIQUID SAMPLES | |
| CN107192709A (en) | A kind of heavy metal nickel ion quick detection test paper and its detection method | |
| Safavi et al. | Catalytic determination of traces of oxalic acid in vegetables and water samples using a novel optode | |
| Temel et al. | Extraction, preconcentration, and quantification of low levels of free formaldehyde from some beverage matrices by combination of ultrasound-assisted-cloud point extraction with spectrophotometry | |
| CN107884402B (en) | Hydrogen peroxide integrated rapid detection tube and method for rapidly detecting hydrogen peroxide | |
| CN102269702A (en) | Detection kit for determining small berry ORAC (oxygen radical absorbance capacity) and detection method thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C02 | Deemed withdrawal of patent application after publication (patent law 2001) | ||
| WD01 | Invention patent application deemed withdrawn after publication |
Open date: 20101201 |