Study of the Determination Method of Protein Content in Chitosan

Objective Using the Coomassie brilliant blue method to solve the problem of the precipitation when detecting the protein content in chitosan. Methods Improving the Coomassie brilliant blue method. Results Use the Coomassie brilliant blue solution with hydrochloric acid concentration of 5% as stain, stain 15 min, the maximum absorption wavelength is 598 nm. the standard curve of absorbance-protein concentration is y=0.003x+0.017 9. r²=0.991, the linear correlation is good within the protein concentration scope of 5 μg/mL~40 μg/mL, the lowest detection limit is 1 μg/mL, and its recovery is 97.8%~103.7%. Conclusions In this paper, the method of determining the content of protein in chitosan is high accurate, stable, reliable and reproducible, and can be widely used in product testing.