[Lactobacillus casei microbiological assay of plasma and RBC concentrations of folic acid with 96-well microtiiter plates].

To investigate the plasma and RBC concentrations of folic acid in normal persons. Microbiological assay was used to determine the plasma and RBC folic acid in 59 normal persons by using of 96-well microtiter plasma. The results showed that the plasma and RBC folio acid concentration were (8.2 +/- 2.9) microgram/L and (337.5 +/- 91.0) microgram/L in male and female normal persons (aged 18 to 32) respectively. The coefficient Variations determined within assay and between assay were 2.2% and 4.7% respectively. This method may reduce reagent costs, shortened the assay time, increase the sensitivity and improve the reproducibility. It can be used for large scale survey.