Simultaneous Quantitation of Flavonol Aglycones in <i>Ginkgo Biloba</i> Leaf Extracts Applying Moving Window Partial Least Squares Regression Models

Abstract

A quantitative near infrared diffuse reflectance spectroscopy method was established for the simultaneous determination of three flavonol aglycones (quercetin, kaempferol and isorhamnetin) in Ginkgo biloba leaf extracts. Partial leat squares was applied to build the correlation models with the pre-processing methods of first derivative and multiplicative scatter correction. A moving window partial least squares method was used for variable selection. Satisfactory calibration statistics were obtained for quercetin, kaempferol and isorhamnetin with coefficients of determination 0.94, 0.90, 0.88; and root mean square error of cross-validation / prediction of 0.61 / 0.48, 0.80 / 0.94, 0.28 / 0.30, respectively. This method demonstrates the great potential of NIR spectroscopy as a non-destructive and efficient tool for quality control of Ginkgo biloba leaf extracts manufacture.