SE512818C2 - Method and test device for determining urea - Google Patents
Method and test device for determining ureaInfo
- Publication number
- SE512818C2 SE512818C2 SE9103370A SE9103370A SE512818C2 SE 512818 C2 SE512818 C2 SE 512818C2 SE 9103370 A SE9103370 A SE 9103370A SE 9103370 A SE9103370 A SE 9103370A SE 512818 C2 SE512818 C2 SE 512818C2
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- Sweden
- Prior art keywords
- indicator
- buffer
- urea
- base
- test device
- Prior art date
Links
- XSQUKJJJFZCRTK-UHFFFAOYSA-N Urea Chemical compound NC(N)=O XSQUKJJJFZCRTK-UHFFFAOYSA-N 0.000 title claims abstract description 30
- 239000004202 carbamide Substances 0.000 title claims abstract description 30
- 238000000034 method Methods 0.000 title claims description 24
- 239000008267 milk Substances 0.000 claims abstract description 19
- 210000004080 milk Anatomy 0.000 claims abstract description 19
- 235000013336 milk Nutrition 0.000 claims abstract description 19
- 108010046334 Urease Proteins 0.000 claims abstract description 11
- 239000003153 chemical reaction reagent Substances 0.000 claims abstract description 10
- 239000000872 buffer Substances 0.000 claims description 19
- 239000000203 mixture Substances 0.000 claims description 19
- 238000006243 chemical reaction Methods 0.000 claims description 11
- 239000008363 phosphate buffer Substances 0.000 claims description 6
- 159000000000 sodium salts Chemical class 0.000 claims description 4
- ZPLCXHWYPWVJDL-UHFFFAOYSA-N 4-[(4-hydroxyphenyl)methyl]-1,3-oxazolidin-2-one Chemical compound C1=CC(O)=CC=C1CC1NC(=O)OC1 ZPLCXHWYPWVJDL-UHFFFAOYSA-N 0.000 claims description 3
- BELBBZDIHDAJOR-UHFFFAOYSA-N Phenolsulfonephthalein Chemical compound C1=CC(O)=CC=C1C1(C=2C=CC(O)=CC=2)C2=CC=CC=C2S(=O)(=O)O1 BELBBZDIHDAJOR-UHFFFAOYSA-N 0.000 claims description 3
- 229960003531 phenolsulfonphthalein Drugs 0.000 claims description 3
- 239000007787 solid Substances 0.000 claims description 3
- NESLWCLHZZISNB-UHFFFAOYSA-M sodium phenolate Chemical compound [Na+].[O-]C1=CC=CC=C1 NESLWCLHZZISNB-UHFFFAOYSA-M 0.000 claims description 2
- 239000003513 alkali Substances 0.000 abstract 2
- 235000013877 carbamide Nutrition 0.000 description 25
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 6
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 6
- 239000011888 foil Substances 0.000 description 5
- 239000007788 liquid Substances 0.000 description 5
- FHVDTGUDJYJELY-UHFFFAOYSA-N 6-{[2-carboxy-4,5-dihydroxy-6-(phosphanyloxy)oxan-3-yl]oxy}-4,5-dihydroxy-3-phosphanyloxane-2-carboxylic acid Chemical compound O1C(C(O)=O)C(P)C(O)C(O)C1OC1C(C(O)=O)OC(OP)C(O)C1O FHVDTGUDJYJELY-UHFFFAOYSA-N 0.000 description 3
- 239000004809 Teflon Substances 0.000 description 3
- 229920006362 Teflon® Polymers 0.000 description 3
- 229940072056 alginate Drugs 0.000 description 3
- 235000010443 alginic acid Nutrition 0.000 description 3
- 229920000615 alginic acid Polymers 0.000 description 3
- 229910021529 ammonia Inorganic materials 0.000 description 3
- 229910000403 monosodium phosphate Inorganic materials 0.000 description 3
- 235000019799 monosodium phosphate Nutrition 0.000 description 3
- 238000007430 reference method Methods 0.000 description 3
- AJPJDKMHJJGVTQ-UHFFFAOYSA-M sodium dihydrogen phosphate Chemical compound [Na+].OP(O)([O-])=O AJPJDKMHJJGVTQ-UHFFFAOYSA-M 0.000 description 3
- 241000283690 Bos taurus Species 0.000 description 2
- 239000003086 colorant Substances 0.000 description 2
- 239000007793 ph indicator Substances 0.000 description 2
- 239000011148 porous material Substances 0.000 description 2
- 229940096055 prax Drugs 0.000 description 2
- 210000002700 urine Anatomy 0.000 description 2
- WQZGKKKJIJFFOK-GASJEMHNSA-N Glucose Natural products OC[C@H]1OC(O)[C@H](O)[C@@H](O)[C@@H]1O WQZGKKKJIJFFOK-GASJEMHNSA-N 0.000 description 1
- 150000003863 ammonium salts Chemical class 0.000 description 1
- 239000002585 base Substances 0.000 description 1
- 239000008280 blood Substances 0.000 description 1
- 210000004369 blood Anatomy 0.000 description 1
- 238000007598 dipping method Methods 0.000 description 1
- 239000008103 glucose Substances 0.000 description 1
- 230000007062 hydrolysis Effects 0.000 description 1
- 238000006460 hydrolysis reaction Methods 0.000 description 1
- 238000005192 partition Methods 0.000 description 1
- 210000002381 plasma Anatomy 0.000 description 1
- 230000035484 reaction time Effects 0.000 description 1
- 150000003839 salts Chemical class 0.000 description 1
- 239000004094 surface-active agent Substances 0.000 description 1
- 150000003672 ureas Chemical class 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
- G01N33/02—Food
- G01N33/04—Dairy products
-
- C—CHEMISTRY; METALLURGY
- C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
- C12Q—MEASURING OR TESTING PROCESSES INVOLVING ENZYMES, NUCLEIC ACIDS OR MICROORGANISMS; COMPOSITIONS OR TEST PAPERS THEREFOR; PROCESSES OF PREPARING SUCH COMPOSITIONS; CONDITION-RESPONSIVE CONTROL IN MICROBIOLOGICAL OR ENZYMOLOGICAL PROCESSES
- C12Q1/00—Measuring or testing processes involving enzymes, nucleic acids or microorganisms; Compositions therefor; Processes of preparing such compositions
- C12Q1/58—Measuring or testing processes involving enzymes, nucleic acids or microorganisms; Compositions therefor; Processes of preparing such compositions involving urea or urease
Landscapes
- Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Health & Medical Sciences (AREA)
- Engineering & Computer Science (AREA)
- Organic Chemistry (AREA)
- Food Science & Technology (AREA)
- Biochemistry (AREA)
- Analytical Chemistry (AREA)
- Proteomics, Peptides & Aminoacids (AREA)
- Immunology (AREA)
- General Health & Medical Sciences (AREA)
- Zoology (AREA)
- Physics & Mathematics (AREA)
- Wood Science & Technology (AREA)
- Bioinformatics & Cheminformatics (AREA)
- Biophysics (AREA)
- General Engineering & Computer Science (AREA)
- Molecular Biology (AREA)
- Microbiology (AREA)
- Genetics & Genomics (AREA)
- Biotechnology (AREA)
- Medicinal Chemistry (AREA)
- General Physics & Mathematics (AREA)
- Pathology (AREA)
- Investigating Or Analysing Biological Materials (AREA)
- Measuring Or Testing Involving Enzymes Or Micro-Organisms (AREA)
- Investigating Or Analysing Materials By The Use Of Chemical Reactions (AREA)
Abstract
Description
15 20 25 30 35 512 818 2 bestämningen, bör den utföras hos korna i ladugården som en sk. "cow side"-snabbtest. Ovannämnda förfarande lämpar sig inte för sådant, eftersom det bör utföras i ett laboratorium. 15 20 25 30 35 512 818 2 determination, it should be performed on the cows in the barn as a so-called. "cow side" quick test. The above procedure is not suitable for such, as it should be performed in a laboratory.
Urea kan även bestämmas så att ett prov som innehåller urea reageras med ureas, och en ändring i pH som hydrolysprodukten åstadkommer observeras med hjälp av en lämplig indikator. Förfarandet används för bestäm- ning av ureahalten i t.ex. blod, plasma och urin (GB- patentskriften 922 665). Härpå baserade teststickor för mjölk anförs :L publikationen Tierärtzl. Prax. 1985, l3:559.Urea can also be determined so that a sample containing urea is reacted with urease, and a change in pH caused by the hydrolysis product is observed by means of a suitable indicator. The method is used to determine the urea content in e.g. blood, plasma and urine (GB patent specification 922 665). Test strips for milk based on this are given: L publication Tierärtzl. Prax. 1985, l3: 559.
Teststickorna har allmänt den nackdelen att man med dem kan analysera enbart en mycket liten provmängd, varvid det erhållna resultatet ofta blir otillförlit- ligt. Resultatet varierar på grund av den ringa prov- mängden och testutövarens sätt att pipettera provet på stickan eller doppa stickan i lösningen som skall under- sökas. Detta problem blir värre av att då teststickan doppas i mjölk, stör mjölken i sig den exakta tolknin- gen av färgändringen på stickan. För att eliminera mjöl- kens störande verkan har man utvecklat stickor i vilka engreaktionszon som kommer i kontakt med'mjölken är placerad intill en indikatorzon (FI-ansökningsskrift 891920). Reaktionszonen innehåller ureas, bas, glukos och tensid. Stickan hålls i ett rör, som är slutet en- bart i ena änden, tills ammoniaken som frigörs från reaktionszonen diffunderat i indikatorzonen, vilket tar lång tid. Stickorna avläses företrädesvis först efter två timmar.The test strips generally have the disadvantage that only a very small amount of sample can be analyzed with them, whereby the result obtained often becomes unreliable. The result varies due to the small amount of sample and the test practitioner's way of pipetting the sample on the dipstick or dipping the dipstick in the solution to be examined. This problem is exacerbated by the fact that when the test strip is dipped in milk, the milk itself interferes with the exact interpretation of the color change on the strip. In order to eliminate the disturbing effect of the milk, sticks have been developed in which meadow reaction zones that come into contact with the milk are located next to an indicator zone (FI application document 891920). The reaction zone contains urease, base, glucose and surfactant. The stick is held in a tube, which is closed only at one end, until the ammonia released from the reaction zone diffuses into the indicator zone, which takes a long time. The sticks are preferably read only after two hours.
Man har nu uppfunnit ett förfarande för be- stämning av urea, vilket förfarande är tillförlitligare än i mjölk nedsänkbara stickor och snabbare än stickor med indikatorzonen placerad intill den nedsänkbara reak- tionszonen och som under reaktionstiden hålls i ett rör 10 15 20 25 30 35 512 818 3 vars ena ända är tillsluten.A method has now been invented for the determination of urea, which method is more reliable than milk-submersible sticks and faster than sticks with the indicator zone placed next to the submersible reaction zone and which is kept in a tube during the reaction time. 10 15 20 25 30 35 512 818 3 one end of which is closed.
Förfarandet och testanordningen enligt uppfin- ningen kännetecknas av det som anges i patentkraven. I förfarandet reageras provet med ureas och bas, och åt- minstone reaktionen med basen utförs i ett slutet utrym- me, vari indikatorsystemet är placerat så att det inte berör övriga reagenser. Provet kan först bringas att reagera med ureas och först därefter med bas, varvid åtminstone den sistnämnda reaktionen utförs i nämnda slutna utrymme. Om provet däremot reageras samtidigt med ureas och bas, utförs hela reaktionen i slutet utrymme.The method and test device according to the invention are characterized by what is stated in the claims. In the process, the sample is reacted with urease and base, and at least the reaction with the base is carried out in an enclosed space, in which the indicator system is positioned so that it does not touch the other reagents. The sample can first be reacted with urease and only then with base, at least the latter reaction being carried out in said closed space. If, on the other hand, the sample is reacted simultaneously with urease and base, the whole reaction is carried out in a closed space.
Testanordningen omfattar ett slutet utrymme, vari åt- minstone reaktionen med basen utförs och vari indikator- systemet är beläget så att det inte kommer i kontakt med övriga reagenser.The test device comprises an enclosed space, in which at least the reaction with the base is carried out and in which the indicator system is located so that it does not come into contact with other reagents.
Reaktionsreagenserna omfattar ureas och bas.The reaction reagents include urease and base.
Ureasen sönderdelar provet som skall undersökas till ammoniumsalter, och basen frigör ammoniaken från salter- na. Ammoniaken absorberas i indikator-systemet och åstad- kommer en färgändring i pH-indikatorn inom en given tid.The urea decomposes the sample to be tested for ammonium salts, and the base releases the ammonia from the salts. The ammonia is absorbed in the indicator system and causes a color change in the pH indicator within a given time.
Indikatorsystemet omfattar en eller flera pH- indfkatorer. I allmänhet löses indikatorn i'en lämplig buffert. dylika buf- fert/indikatorblandningar som ändrar färg vid olika pH- Man kan även använda flera värden. Bestämningen av mjölkens ureahalt utförs före- trädesvis i form av en sk. dubbeltest. Företrädesvis är den ifrågavarande dubbeltestens buffert/indikator- blandningar sådana att ureahalten < 20 mg/100 ml ännu inte åstadkommer någon färgändring i nágondera buf- fert/indikatorblandningen, men vid en halt av 20 - 30 mg/IOO ml reagerar den ena buffert/indikatorblandningen, och då urea finns i en mängd över 30 mg/100 ml reage- rar båda buffert/indikatorblandningarna.The indicator system comprises one or more pH indicators. In general, the indicator is dissolved in a suitable buffer. such buffer / indicator mixtures that change color at different pH- Several values can also be used. The determination of the urea content of the milk is preferably performed in the form of a so-called. double test. Preferably, the buffer / indicator mixtures of the double test in question are such that the urea content <20 mg / 100 ml does not yet cause any color change in any buffer / indicator mixture, but at a level of 20-30 mg / 100 ml one buffer / indicator mixture reacts , and when urea is present in an amount above 30 mg / 100 ml, both buffer / indicator mixtures react.
Företrädesvis innehåller vardera buffert/indi- 10 15 20 25 30 35 512 818 4 katorblandningen fosfatbuffert, men av olika koncentra- tion. Företrädesvis innehåller fosfatbuffertarna nat- riumsalt av fenolrött och natriumsalt av bromtymolblått t.ex. i viktförhållandet 1:1. Den ena fosfatbufferten är företrädesvis en 0,00025M och den andra en 0,00230M natriumdivätefosfatbuffert.Preferably, each buffer / indicator mixture contains phosphate buffer, but of different concentration. Preferably the phosphate buffers contain sodium salt of phenol red and sodium salt of bromothymol blue e.g. in the weight ratio 1: 1. One phosphate buffer is preferably a 0.00025M and the other a 0.00230M sodium dihydrogen phosphate buffer.
Indikatorsystemet kan vara i fast eller flytan- de form. Ett indikatorsystem i flytande form kan avskil- jas från övriga reagenser med en gasgenomsläpplig folie.The indicator system can be in solid or liquid form. An indicator system in liquid form can be separated from other reagents with a gas-permeable foil.
Folien kan vara t.ex. teflonrörtejp eller teflonfilter- folie med en porstorlek av 0,5 pm. Indikatorsystemet kan företrädesvis bringas i fast form med hjälp av alginat och/eller genom att låta det absorberas i ett filtrer- papper och torka.The foil can be e.g. Teflon tube tape or Teflon filter foil with a pore size of 0.5 μm. The indicator system can preferably be solidified by means of alginate and / or by allowing it to be absorbed into a filter paper and dried.
Indikatorsystemet placeras företrädesvis i locket av ett tillslutbart kärl. Locket kan vara två- delat, varvid två olika buffert/indikatorblandningar placeras i det. Ureasen, provet och basen appliceras på kärlets botten och locket tillsluts tätt. Efter en given tid avläses indikatorsystemets färger. Förfarandet en- ligt uppfinningen lämpar sig speciellt för bestämning av ureahalten i mjölk, men även andra prov, såsom urin- gprov, kan komma i fråga.The indicator system is preferably placed in the lid of a closable vessel. The lid can be divided into two parts, with two different buffer / indicator mixtures being placed in it. The urea, sample and base are applied to the bottom of the vessel and the lid is tightly closed. After a given time, the colors of the indicator system are read. The process according to the invention is particularly suitable for determining the urea content in milk, but other samples, such as urine samples, may also be considered.
Uppfinningen belyses med hjälp av följande icke-restriktiva exempel.The invention is illustrated by the following non-restrictive examples.
Exempel 1.Example 1.
Buffert/indikatorblandning I, som innehåller 25 mg natriumsalt av fenolrött, 25 mg natriumsalt av bromtymolblått och 3 g alginat per 100 ml 0,00025M nat- riumdivätefosfat, absorberas i ett filtrerpapper. Buf- fert/indikatorblandning II, som är lik I förutom att natriumdivätefosfatetskoncentrationärCL00230M,absor- beras i ett annat filterpapper. Pappren torkas vid 90 °C 10 15 20 25 30 35 512 818 5 i 60 min. och placeras därefter i ett tvádelat lock av ett 10 mlzs kärl med tätt-slutande lock sålunda att pappren skiljs åt av en mellanvägg i locket. Ureas (ca 60 - 250 U) i fast eller flytande form appliceras på kärlets botten. I kärlet tillsätts l ml mjölk och efter 2,5 minuter 0,5 - 1 ml 0,lM NaOH, och locket läggs pà.Buffer / indicator mixture I, which contains 25 mg of sodium salt of phenol red, 25 mg of sodium salt of bromothymol blue and 3 g of alginate per 100 ml of 0.00025M sodium dihydrogen phosphate, is absorbed in a filter paper. Buffer / indicator mixture II, which is similar to I except that the sodium dihydrogen phosphate concentrator CL00230M is absorbed in another filter paper. The papers are dried at 90 ° C for 60 minutes. and then placed in a two-part lid of a 10 ml container with a tight-fitting lid so that the papers are separated by a partition in the lid. Ureas (approx. 60 - 250 U) in solid or liquid form are applied to the bottom of the vessel. In the vessel add 1 ml of milk and after 2.5 minutes 0.5 - 1 ml of 0.1 M NaOH, and put the lid on.
Efter 2,5 minuter avläses de i testkärlets lock bildade färgerna av buffert/indikatorblandningarna I och II.After 2.5 minutes, the colors of the buffer / indicator mixtures I and II formed in the lid of the test vessel are read.
Resultaten jämförs med en färgkarta och tolkas enligt följande: Färgkombinationen Provets ureahalt i testkärlets lock mg/100 ml gul/gul < 20 orange-röd/gul 20 - 30 orange-röd/orange-röd > 30 Exempel 2.The results are compared with a color chart and interpreted as follows: The color combination The urea content of the sample in the test vessel cap mg / 100 ml yellow / yellow <20 orange-red / yellow 20 - 30 orange-red / orange-red> 30 Example 2.
Ureahalterna i 118 mjölkprov bestämdes enligt förfarandet enligt exempel 1 och medelst ett spektro- fotometriskt referensförfarande (Fawcett & Scott 1960, SJ. Clin. Path. l3:l56). Resultaten visas i tabell 1.The urea levels in 118 milk samples were determined according to the procedure of Example 1 and by a spectrophotometric reference method (Fawcett & Scott 1960, SJ. Clin. Path. 13: 56). The results are shown in Table 1.
Tabell 1. (st.) olika ureahaltsklasser Fördelning av mjölkproven i Urea mg/100 ml < 20 20-30 > 30 < 20 17 3 - 20-30 2 34 3 > 30 - 8 51 Referensförfarande totalt/st. 19 45 54 118 10 15 20 25 512 818 6 Medelst förfarandet enligt uppfinningen klassi- ficerades 86,4 % av proven i rätt klass jämfört med referensförfarandet. I tabell 2 visas en motsvarande provfördelning med beaktande av den inre deviationen (: 5 %) i referenšförfarandet. Härvid är andelen rätt klas- sificerade prov 94,1 %.Table 1. (pcs.) Different urea content classes Distribution of the milk samples in Urea mg / 100 ml <20 20-30> 30 <20 17 3 - 20-30 2 34 3> 30 - 8 51 Reference procedure total / pcs. 19 45 54 118 10 15 20 25 512 818 6 By means of the method according to the invention, 86.4% of the samples were classified in the correct class compared with the reference method. Table 2 shows a corresponding sample distribution taking into account the internal deviation (: 5%) in the reference procedure. The proportion of correctly classified samples is 94.1%.
Tabell 2. Fördelning (st.) av mjölkproven i olika ureahaltsklasser Urea mg/100ml < 20 20-30 > 30 < 20 18 1 - 20-30 1 40 1 > 30 - 4 - ß 53 Referensförfarandet totalt/st. 19 45 54 118 Exempel 3.Table 2. Distribution (pcs.) Of the milk samples in different urea content classes Urea mg / 100ml <20 20-30> 30 <20 18 1 - 20-30 1 40 1> 30 - 4 - ß 53 The reference procedure total / pcs. 19 45 54 118 Example 3.
Ureahalterna i 64 mjölkprov bestämdes med hjälp “av för gàrdsbruk avsedda teststickor Azostix“(Tierärzl.The urea levels in 64 milk samples were determined using "Azostix test strips" (Tierärzl).
Prax. 1985, 13:559), ovannämnda referensförfarande samt förfarandet enligt uppfinningen. Resultaten 'visas i tabellerna 3 och 4. 10 15 20 25 30 35 512 818 7 Tabell 3. Fördelning (st.) av mjölkproven i olika ureahaltsklasser medelst test- stickan Urea mg/100ml < 20 20-30 > 30 < 20 7 - - 20-30 6 21 5 > 30 - l 24 Referensförfarandet totalt/st. 13 22 28 64 Med hjälp av teststickan klassificerades 82,8 % av proven (53/64) i rätt klass.Prax. 1985, 13: 559), the above-mentioned reference method and the method according to the invention. The results are shown in Tables 3 and 4. 10 15 20 25 30 35 512 818 7 Table 3. Distribution (pcs.) Of the milk samples in different urea content classes by means of the test strip Urea mg / 100ml <20 20-30> 30 <20 7 - - 20-30 6 21 5> 30 - l 24 Total reference procedure / pc. 13 22 28 64 Using the test strip, 82.8% of the samples (53/64) were classified in the correct class.
Tabell 4. Fördelning av mjölkproven i olika ureahaltsklasser medelst förfarandet enligt uppfinningen Urea mg/100ml < 20 20-30 > 30 “< 2077 13 2 - 20-30 - 17 2 > 30 - 3 27 Referensförfarandet totalt/st. 13 QZ 29 64 Medelst förfarandet enligt uppfinningen klassi- fiserades 89,1 % av proven (57/64) i rätt klass.Table 4. Distribution of the milk samples in different urea content classes by means of the process according to the invention Urea mg / 100ml <20 20-30> 30 “<2077 13 2 - 20-30 - 17 2> 30 - 3 27 The reference procedure total / pc. 13 QZ 29 64 By means of the process according to the invention, 89.1% of the samples (57/64) were classified in the correct class.
Exempel 4.Example 4.
I ett 4 mlzs kärl tillsattes 0,5 ml av den i 10 15 20 25 30 512 818 8 exempel 1 nämnda buffert/indikatorblandningen I i fly- tande form, dvs. utan alginat. Kärlets mynning täcktes med en teflonfolie med en porstorlek av 0,5 pm. I ett annat likadant kärl tillsattes 0,2 ml mjölk och ca 15 U ureas. Efter 2,5 minuter tillades 200 ul O,lM NaOH.In a 4 ml vessel, 0.5 ml of the buffer / indicator mixture I mentioned in Example 1 mentioned in liquid form, i.e. without alginate. The mouth of the vessel was covered with a Teflon foil with a pore size of 0.5 μm. In another similar vessel, 0.2 ml of milk and about 15 U of urease were added. After 2.5 minutes, 200 μl of 0.1 M NaOH was added.
Kärlet med buffert/indikatorblandningen och kärlet med provet och de övriga reagenserna förenades med tejp så att mynningarna ställdes mot varandra och ett helt till- slutet utrymme erhölls, i vilket utrymme en gasgenom- släpplig folie skilde buffert/indikatorblandningen fràn de övriga reagenserna. De sålunda förenade kärlen blan- dades i. l minut, varefter indikatorblandningens färg avlästes. En parallell bestämning utfördes med den i exempel 1 nämnda buffert/indikatorblandningen II i fly- tande form. Resultaten tolkades på samma sätt som i exempel 1. Ureahalter för 24 mjölkprov bestämdes. 87,5 % av proven klassificerades i rätt klass. Resultaten visas i tabell 5.The vessel with the buffer / indicator mixture and the vessel with the sample and the other reagents were taped so that the orifices were set against each other and a completely closed space was obtained, in which space a gas-permeable foil separated the buffer / indicator mixture from the other reagents. The vessels thus combined were mixed for 1 minute, after which the color of the indicator mixture was read. A parallel determination was performed with the buffer / indicator mixture II mentioned in Example 1 in liquid form. The results were interpreted in the same manner as in Example 1. Urea levels for 24 milk samples were determined. 87.5% of the samples were classified in the correct class. The results are shown in Table 5.
Tabell 5. (st.) olika ureahaltsklasser Fördelning av mjölkproven i 'Urea mg/l00ml < 20 20-30 > 30* < 20 6 - - 120-30 l 8 1 > 30 _ - 1 Referensförfarandet totalt/st. 7 9 8 24Table 5. (pcs.) Different urea content classes Distribution of the milk samples in 'Urea mg / l00ml <20 20-30> 30 * <20 6 - - 120-30 l 8 1> 30 _ - 1 The reference procedure total / pcs. 7 9 8 24
Claims (8)
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FI905949A FI88310C (en) | 1990-12-03 | 1990-12-03 | Method and means for determining urea |
Publications (3)
| Publication Number | Publication Date |
|---|---|
| SE9103370D0 SE9103370D0 (en) | 1991-11-14 |
| SE9103370L SE9103370L (en) | 1992-06-04 |
| SE512818C2 true SE512818C2 (en) | 2000-05-22 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| SE9103370A SE512818C2 (en) | 1990-12-03 | 1991-11-14 | Method and test device for determining urea |
Country Status (7)
| Country | Link |
|---|---|
| DK (1) | DK195091A (en) |
| EE (1) | EE02945B1 (en) |
| FI (1) | FI88310C (en) |
| GB (1) | GB2250590A (en) |
| IE (1) | IE913920A1 (en) |
| NO (1) | NO302387B1 (en) |
| SE (1) | SE512818C2 (en) |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2731276A1 (en) * | 1995-03-03 | 1996-09-06 | D Aquitaine Comp Chimique | Test strip for urea determn. in milk |
| EP1754973B1 (en) * | 2005-07-26 | 2010-11-03 | Raudszus Electronic GmbH | Method and device for sampling and directly analysing collected flowable material, in particular milk deliveries |
| CN102539421A (en) * | 2010-12-21 | 2012-07-04 | 内蒙古蒙牛乳业(集团)股份有限公司 | Method for qualitatively detecting urea in milk |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE2711634A1 (en) * | 1977-03-17 | 1978-09-21 | Riedel De Haen Ag | Test kit for urea determn. esp. in serum - comprising spaced reaction and indicator zones in a container and used e.g. to diagnose renal insufficiency |
| EP0339331A3 (en) * | 1988-04-29 | 1990-09-19 | ARZNEIMITTELWERK DRESDEN GmbH | Test strip for the determination of urea, and its use |
-
1990
- 1990-12-03 FI FI905949A patent/FI88310C/en not_active IP Right Cessation
-
1991
- 1991-11-11 IE IE392091A patent/IE913920A1/en not_active Application Discontinuation
- 1991-11-14 SE SE9103370A patent/SE512818C2/en not_active IP Right Cessation
- 1991-11-26 GB GB9125040A patent/GB2250590A/en not_active Withdrawn
- 1991-11-29 NO NO914711A patent/NO302387B1/en not_active IP Right Cessation
- 1991-12-02 DK DK195091A patent/DK195091A/en not_active Application Discontinuation
-
1994
- 1994-07-11 EE EE9400033A patent/EE02945B1/en not_active IP Right Cessation
Also Published As
| Publication number | Publication date |
|---|---|
| FI88310C (en) | 1993-04-26 |
| GB2250590A (en) | 1992-06-10 |
| FI905949A0 (en) | 1990-12-03 |
| NO302387B1 (en) | 1998-02-23 |
| FI88310B (en) | 1993-01-15 |
| SE9103370L (en) | 1992-06-04 |
| NO914711D0 (en) | 1991-11-29 |
| FI905949L (en) | 1992-06-04 |
| IE913920A1 (en) | 1992-06-03 |
| SE9103370D0 (en) | 1991-11-14 |
| DK195091A (en) | 1992-06-04 |
| EE02945B1 (en) | 1996-10-15 |
| DK195091D0 (en) | 1991-12-02 |
| NO914711L (en) | 1992-06-04 |
| GB9125040D0 (en) | 1992-01-22 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| NUG | Patent has lapsed |