TY - JOUR T1 - Microbiological assay for vitamin B12 performed in 96-well microtitre plates. JF - Journal of Clinical Pathology JO - J Clin Pathol SP - 592 LP - 595 DO - 10.1136/jcp.44.7.592 VL - 44 IS - 7 AU - B P Kelleher AU - S D Broin Y1 - 1991/07/01 UR - http://jcp.bmj.com/content/44/7/592.abstract N2 - 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 new assay correlated well with a more conventional "tube" assay and was not influenced by the presence of antibiotics in serum. Evaluation of assay performance showed excellent interassay and intra-assay precision with quantitative recovery of added cyanocobalamin over a wide range of additions (94.9%-102.1%). The advantages of short incubation time, easy reading, and minimal reagent costs make this assay an attractive option in the routine clinical laboratory and in research. ER -