Development of a Rapid Method for Raw Silk Sericin Content Determination

Gravimetric method is widely used in industry for raw silk sericin content evaluation, even so, some weakness are still existed obviously like heavier working load, lower accuracy, and time concerning. In this paper, a new fast sericin content measurement method is reported. The new developed method includes a thermogravimetric analysis (TGA) as the apparatus, and a new prediction model. Based on the analysis of standardized TGA measuring curves for pure fibroin, pure sericin and raw silk curve, developed silk sericin content calculation model can predicate silk sericin content (K-TG) from the difference of areas which surrounded by measured curve of raw silk material and pure fibroin as well as pure sericin and raw silk respectively. The whole evaluation process can be completed within 50 minutes without sample washing, equilibrium and weighting requirements which significantly improve the efficiency of measurement and accuracy. For purpose of verify the reliability of the method, traditional degumming method was applied on the same raw silk material to evaluated the silk sericin content. A closed relationship was observed between the new developed method and gravimetric method of raw silk gum (K-W) with a very high correlation coefficient R-2 = 0.9996.