Dose response curve linearization and computer potency calculation of turbidimetric microbiological vitamin assays.

The dose response curves of various turbidimetric microbiological assays, including vitamin B(12), Ca pantothenate, and pyridoxine (vitamin B(6)), were linear with logarithmic transformation of the responses by use of the equation derived, ln[T(x) - T(infinity)] = ln A - Bx. A Fortran computer program which used the slope ratio potency calculation was written. The assay potencies calculated by the computer program showed excellent agreement with those obtained by the manual calculation.