Methods for the analysis of vitamin b12 include microbiological assay, polarographic. Microbiological assay of vitamin b12 with a mutant strain of escherichia coli. Peterson department of biochemistry, college of agriculture, university of wisconsin, madison, wisconsin. A quantitative method for the determination of vitamin b12 in meat products by rphplc and uv detection was developed and compared to the reference method microbiological assay, mba. A simplified microbiological assay for vitamin b12 estimation, completed on microtitre plates using a colistin sulphate resistant strain of lactobacillus leichmannii ncib 12519, and cryopreserved cultures is described. The microtiter plate provided in this kit has been precoated with an antibody specific to vitamin b12. B12 assay agar using li mutant culture harrison et al. Vitaminb12 and vitamind can be analyzed by immunoassays.
As a result, vitamin b12 deficiency affects between 1. Microbiological assay of vitamin b12 with a mutant strain. For few samples immunoassays are considered expensive but cost can be reduced if sufficient samples are batch analyzed on a 96well format. Microbiological assay has been the most commonly used assay technique for foods and has been used for the. Ford skip to main content accessibility help we use cookies to distinguish you from other users and to provide you with a better experience on our websites. The invention also provides labeled vitamin b12 compositions made in accordance with the invention. Determination of vitamin b12 in meat products by rphplc. Us8202507b2 assay for vitamin b12 absorption and method of. The first, working standard 1 ws1, was used for demonstrating chromatographic separation and retention time rt reproducibility.
Intended purpose the eagle biosciences vitamin b 6 hplc assay is intended for the quantitative determination of vitamin b 6 in serum and plasma. Many of the papers in the literature give values of vitamin b12 in food that are false because as much as 80% of the activity by this method is due to inactive analogues of vitamin b12. According to the applicants, vitamin b12cyanocobalamin is produced by. Microbiological assay of cyanocobalamin or vitamin b12. Principles of the procedure vitamin b 12 assay medium is a vitamin b 12free medium. It was in 1948 that vitamin b12 was first isolated from liver juice, and it was used in treating pernicious anemia 2. Methodologic problems may compromise the sensitivity and specificity of current vitamin b12 assays.
Vitb12 deficiency causes macrolyticanemia, pernicious anemia. Oct 09, 2012 replication repeat the entire determination at least once, using separately prepared assay preparations. Targetspecific elisa kits are available from a variety of manufacturers and can help streamline your immunodetection experiments. There is no gold standard test for b12 deficiency because as a b12. It was first described by capp et al 1 and is recommended by usp 2 and aoac 3, using lactobacillus leichmannii atcc 7830 as the test organism. The vitamin b 6 hplc assay kit is for research use only and not to be used in diagnostic procedures. Your doctor can test your vitamin b12 level to see if you have a. Pdf comparison of four automated serum vitamin b12 assays. Although cobalamin vitamin b12 deficiency was described over a century. It is crucial for the construction of dna, production of red blood cells and aids in the maintenance of a healthy nervous system. Medium m110 b12 assay agar using li mutant culture is recommended for the microbiological assay of vitamin b12 by plate method using li mutant 13 davis atcc 11105 as a test organism. Get a printable copy pdf file of the complete article 337k, or click on a page image.
Microbiological assay of vitamin b 12 with a mutant strain of escherichia coli. These assays are commercially available in kit form. Affected patients may experience weakness, irritability, jaundice, cognitive impairment. Structure is similar to that of heme where the iron is replaced with cobalt as a centre of molecule. Box 146, 11152 belgrade, serbia and montenegro received 12 march 2004, revised 8 december. Vitamin b12 consists of corrin ring synthesized by bacteria and cobalt ion. Vitamin b12 was extracted with 50 mm sodium acetate buffer in the presence of sodium cyanide. So, auxotrophic strain of li is unable to grow on media.
Replication repeat the entire determination at least once, using separately prepared assay preparations. In 1987 the introduction of a colistin sulfate resistant strain of l leichmannii. Comparison of automated assays for the determination of vitamin b12 in serum article in clinical biochemistry 401617. Certain other clinical states may also lead to vitamin deficiencies malabsorption syndromes, etc. Vitamin b12 assay medium is a vitamin b12 free medium containing all other nutrients and vitamins essential for the cultivation of test organism. Comparison of four automated serum vitamin b12 methods on the xaxis with mma results measured by lcms method on the yaxis. In humans, it is obtained only from animal proteins and requires.
This medium is specially utilized for the microbiological assay of vitamins. Principle of the assay the elisa is based on the competitive binding enzyme immunoassay technique. The abbott architect activeb12 assay is a test for detecting levels of serum holotranscobalamin, which is the metabolically available component of vitaminb12, and can be used as a marker of vitaminb12 deficiency. The assay is performed by combining serum or a whole blood hemolysate sample with 125ifolate and 57covitamin b12 in a solution. Measurement of vitamin b12 is for the assessment of vitamin b12 sufficiency. Cms policy for arkansas, colorado, louisiana, mississippi, new mexico, oklahoma, and texas local policies are determined by the performing test location. Since a deficiency of either vitamin may be the cause of megaloblastic anemia, it is essential to determine the levels of both vitamin b12 and folic acid to establish the etiology of the anemia. Microbiological assay of vitamin b 12 with a mutant strain of escherichia coli 1 j. Composition formula adjusted, standardized to suit performance parameters directions.
Lcd l30551 vitamin b12 assays print carroll hospital. Labs can perform one extraction step on the sample and run either analyte using the same calibrators and kit. Vitamin b12, assay for folic acid, assay of homocystine assays for vitamins and metabolic function coverage indications, limitations, andor medical necessity notice. B12 deficiency damages the brain, spinal cord, peripheral nerves, and nerves of the eye. Microbiological assay of vitamins is a type of biological assay performed with the aid of microorganisms. Vitamin b12 cobalamin is necessary for hematopoiesis and normal neuronal function. Monobind offers a convenient anemia panel vast product that combines folate and vitamin b12. The invention provides methods for labeling vitamin b12 with 14 c, c, tritium, and deuterium. The microbiological assay of vitamin b12 volume 6 issue 1 j. Many other conditions are known to cause an increase or decrease in the serum vitamin b 12 concentration including.
These assays however depend upon availability of monoclonal antibodies that determine their specificity and sensitivity. Add 1 ml of inoculum of li m 200 of required thickness. The serum cyanocobalamin is a quantitative analysis of serum vitamin b12 levels. The lancet occasional survey problems with the serum vitamin b12 assay j. It is not appropriate to bill medicare for services that are not covered as described by this entire lcd as if they are covered. It was prepared by weighing out 80 320 g ml of each of the eight vitamins, depending on the vitamins relative absorptivity. Active b12 assay for diagnosing vitamin b12 deficiency nice. Rphplc determination of vitamins b, folic acid 12 in. These antibodies may interfere with the assay reagents to produce unreliable results. Vitamin b12 assay medium is a vitamin b12free medium containing all other nutrients and vitamins essential f or the cultivation of l. Microbiological assay of vitamin b12 in the presence of tetracycline. Microbiological assay of vitamin b12 with a mutant strain of. Supported in part by a grant from the red star yeast and products company, milwaukee, wisconsin.
Diazymes vitamin b12 assay is a cost effective four vial liquid stable reagent system intended for the in vitro quantitative determination of vitamin b12 in human serum on automated chemistry analyzers roches modular p and similar. Vitamin b12, also known as cobalamin, is a watersoluble vitamin involved in the metabolism of. Principles of assay procedures assay colorimetric spectrophotometric hplc advantages simple rapid inexpensive sensitive rapid inexpensive. Diagnostic evaluation should be targeted at the specific vitamin deficiency or deficiencies suspected. Diagnosing vitamin b12 deficiency on the basis of serum b12. Microbiological assay of vitamin b12 with a mutant strain of escherichia.
A differential microbiological assay for vitamin b12 and. The most practical and least expensive measurements at the population level are serum or plasma folate and vitamin b12. Vitamin b12 is of singular interest in any discussion of vegetarian diets because this vitamin is not found in plant foods as are other vitamins. The diagnosis of vitamin b12 deficiency has always been problematic owing to the unavailability of a robust assay. Vitamin b12 activity for chicks and for different microorganisms of gut contents and faeces. The microbiological assay of vitamin b12 british journal. Medicare local coverage determination policy vitamin b12.
Vitamin b12 cobalamin is one of the vitamins essential to human health and life. The spectrophotometric method can be used to monitor vitamin a levels in fortified products at the production level. Vitamin b12 deficiency can occur if the body does not absorb enough vitamin b12 from the gastrointestinal tract or when there is not enough dietary intake of the vitamin, which is more common in people who have vegan diets and to a lesser extent, vegetarian diets devalia et al. Problems with the serum vitamin b12 assay sciencedirect.
Some patients who have been exposed to animal antigens either in the environment or as part of treatment or imaging procedure, may have circulating antianimal antibodies present. Vitamin b12 is the initial test to perform in case of megaloblastic anaemia. This article has been cited by other articles in pmc. This is determined by the state in which your performing laboratory resides and where your testing is commonly performed.
Pdf micronutrients added to foods are analyzed using various procedures depending on their nature and properties. Vitamin b12 is an essential cofactor in intermediary metabolism and is required for the biosynthesis of rna and dna. When radioisotopes are used, the invention provides for methods of labeling b12 with high specific activity. Introduction vitamin a and e are fat soluble vitamins. Microbiological assay for vitamin b12 performed in 96well microtitre. Conclusions of a who technical consultation on folate and vitamin. Vitamin b12 assay medium is a vitamin b12 free medium containing all other vitamins and nutrients essential for the growth of lactobacillus leichmannii atcc 7830. Vitamin b12 fact sheet for consumers office of dietary supplements.
Vitamin b12 production by citrobacter freundii or klebsiella pneumoniae during tempeh fermentation and proof of enterotoxin absence by pcr pdf. Red dashed lines on the xaxis showing the upper and lower limits of. Vitamin b12, assay for folic acid, assay of homocystine. Distribute 25 to 30 ml of the inoculated medium in sterile petri plates. During the reaction, vitamin b12 in the sample or standard competes with a fixed amount of biotinlabeled vitamin b12 for sites on a precoated. The elecsys vitamin b12 ii assay employs a competitive test principle using intrinsic factor specific for vitamin b12. Microbiological assay for vitamin b12 with use of a colistinsulfateresistant organism. Comparison of automated assays for the determination of. If the difference between the two log potencies m is not greater than 0. Vitamin b 12 assay medium is prepared according to the formula described by capp, hobbs and fox. Vitamin b12 in the sample competes with the added vitamin b12 labeled with biotin for the binding sites on the rutheniumlabeled intrinsic factor complex. For the microbiological assay of vitamins b 12 in drugs, foodstuffs, animal feed preparations and other materials. Active b12 assay for diagnosing vitamin b12 deficiency.
B12 elisa kits the elisa enzymelinked immunosorbent assay is a widely used application for detecting and quantifying proteins and antigens from various samples. The absorbance is proportional to the vitamin a content in the sample. The vitamin b12 assay principle is for the roche modular p chemistry analyzer. The many faces of cobalamin vitamin b12 deficiency ncbi. Pdf microbiological assay for vitamin b12 performed in.