A Study on the Determination Methods of Sodium Metabisulfite Content in Some Injections

Sodium metabisulfite as an antioxidant in medicines,its content is very important to the effectiveness and safety of medicines and thus needs to be supervised.Current determination methods of sodium metabisulfite are mainly:colorimetric method,titration,rate constant method,rosaniline method,distillation,ion chromatography method,and calcium carbide chromatography.The most common and accurate method is UV?spectrophotometry,upon which the author made determination analysis of sodium metabisulfite content in some injections.Results:the sample appears in a linear relationship ranging 0.10-3.09?g/ml,with regression equation as A=0.3905c-0.0007(r=0.9998).Recovery rates:the Average recovery rates of sodium metabisulfite in injections of three different concentrations are 99.24% in 70%,100.19% in 100%,and 99.78% in 130%,RSD 0.6%.Conclusion:This determination method is reliable,simply-manipulated and accurate to test the content of sodium metabisulfite.