Determination of Amylose and Amylopectin in Ginkgo Biloba by Dual-Wavelength Spectrophotometry

Dual wavelength spectrophotometry was applied to the determination of amylose and amylopectin in ginkgo biloba using iodine as coloring agent.According to the absorption spectra of the two complexes,the wavelength of I 2 amylose,568nm and 420nm,and of I 2 amylopectin,512nm and 648nm,were selected as the measuring wavelength.The content of amylose and amylopectin were figured out from the two regressive equations.Beer's law is obeyed in 0—36μg/mL for amylose and 0—110μg/mL for amylopectin.The recovery rate of both amylose and amylopectin ranged is from 98.3% to 104%.The relative standard deviation is less than 1.30%.