Determination of Concentration of Anthrax Vaccine by Spectrophotometry

Objective To determine the concentration of anthrax vaccine by spectrophotometry. Methods The wavelength and linear range for spectrophotometry of anthrax vaccine were determined, based on which the stability of test samples and repro - ducibility of the method were analyzed. Results The wavelength for spectrophotometry of anthrax vaccine was determined as 600 nm. The A600 value showed a good relationship(r = 0. 999 1, df = 3, P 0. 01)to anthrax vaccine concentration at a range of(0. 25 ～ 1. 25)× 108 bacteria / ml. The stability of test samples increased after treatment with formaldehyde. The method showed high reproducibility. Conclusion Spectrophotometry may be used for determination of anthrax vaccine concentration instead of turbidimetry or as a method for confirmation.