Abstract
This review describes the characteristics of main assays for biotin and problems for standardization. The typical assays for biotin are microbiological assay, binding assay, and HPLC method. Microbiological assay is the initial method of the discovery of biotin. Since then, it has been popularly performed. Lactobacillus plantarum ATCC 8014 is generally used for microbiological assay. It has high sensitivity to biotin, but this strain is affected by biotin catabolites. Binding assay using avidin or streptavidin has been specific against biotin. This method is as simple as immunoassays. Recently, binding assay has obtained high sensitivity by using biochemical luminescence detection. However, this assay cannot separate biotin and biotin analogues. HPLC method is suitable for a standard method, because it is possible to determine biotin and its metabolites. Though various detection methods are combined to HPLC, they have not yet obtained sufficient sensitivity. Therefore, this paper describes the problems of the sample preparation before assay, sensitivity and reference materials for the establishment of a standard method.
