Development, validation and application of first derivative spectroscopy ratio method for estimation of Bradford assay

The sample recoveries for 1D550/1D420 ratio method have proven that its accuracy (95.05%) is within the acceptable interval of recoveries. The obtained 1.55% RSD for precision fell well within the criteria accepted in bioanalytical method validation. This method was applied for determination of total proteins in hair samples. Also, the influence of different chemical treatments on total protein amount in hair sample was investigated.