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. 1973 Jul;26(7):494–498. doi: 10.1136/jcp.26.7.494

An automated microbiological method for the measurement of vitamin B12

R E Davis 1, J Moulton 1, A Kelly 1
PMCID: PMC477802  PMID: 4199360

Abstract

An automated method for the microbiological assay of vitamin B12 is described. A chloramphenicol-resistant strain of Lactobacillus leichmannii is used as the test organism and this eliminates the need for sterilization or aseptic addition. Precipitation of the serum protein is avoided by dilution of the serum with a glutamic/malic acid solution before heating the preparation to free the vitamin B12. Tests can be set up at a rate of 80 an hour and after incubation they can be read at 160 an hour. By interfacing a programmed electronic calculator directly with the Mecolab M which is used for the assays, results are printed directly in ng/l.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. ANNEAR D. I. Recoveries of bacteria after drying on cellulose fibres. A method for the routine preservation of bacteria. Aust J Exp Biol Med Sci. 1962 Feb;40:1–8. doi: 10.1038/icb.1962.1. [DOI] [PubMed] [Google Scholar]
  2. Davis R. E., Nicol D. J., Kelly A. An automated method for the measurement of folate activity. J Clin Pathol. 1970 Feb;23(1):47–53. doi: 10.1136/jcp.23.1.47. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. GIRDWOOD R. H. Microbiological methods of assay in clinical medicine with particular reference to the investigation of deficiency of vitamin B12 and folic acid. Scott Med J. 1960 Jan;5:10–22. doi: 10.1177/003693306000500103. [DOI] [PubMed] [Google Scholar]
  4. LAU K. S., GOTTLIEB C., WASSERMAN L. R., HERBERT V. MEASUREMENT OF SERUM VITAMIN B12 LEVEL USING RADIOISOTOPE DILUTION AND COATED CHARCOAL. Blood. 1965 Aug;26:202–214. [PubMed] [Google Scholar]
  5. MATTHEWS D. M. Observations on the estimation of serum vitamin B12 using Lactobacillus leichmannii. Clin Sci. 1962 Feb;22:101–111. [PubMed] [Google Scholar]
  6. NICHOLAS D. R., PITNEY W. R. Microbiological assay of vitamin B12 content of serum using Euglena gracilis. Aust J Exp Biol Med Sci. 1958 Dec;36(6):603–608. doi: 10.1038/icb.1958.65. [DOI] [PubMed] [Google Scholar]
  7. ROSS G. I. M. Vitamin B12 assay in body fluids. Nature. 1950 Aug 12;166(4215):270–271. doi: 10.1038/166270a0. [DOI] [PubMed] [Google Scholar]
  8. Raven J. L., Robson M. B., Morgan J. O., Hoffbrand A. V. Comparison of three methods for measuring vitamin B 12 in serum: radioisotopic, euglena gracilis and Lactobacillus leichmannii. Br J Haematol. 1972 Jan;22(1):21–31. doi: 10.1111/j.1365-2141.1972.tb08783.x. [DOI] [PubMed] [Google Scholar]
  9. SPRAY G. H. An improved method for the rapid estimation of vitamin B12 in serum. Clin Sci. 1955 Nov;14(4):661–667. [PubMed] [Google Scholar]
  10. SPRAY G. H. The estimation and significance of the level of vitamin B12 in serum. Postgrad Med J. 1962 Jan;38:35–40. doi: 10.1136/pgmj.38.435.35. [DOI] [PMC free article] [PubMed] [Google Scholar]

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