Assay of Borneol by the Color Reaction with Vanillin

Borneol sample or the reference standard of pure borneol was dissolved in absolute alcohol.Through the reaction with vanillin in conc.H2SO4,a rose colored compound was formed by borneol and its isomer,having its absorption maximum at the wavelength of 470 nm.Under optimum conditions,linear relationship between values of absorbance and concentration of borneol was obtained in the range of 0.06-0.30 g·L-1,in respective to the linear regression equation A=2.850 1 C+0.015 6 (r=0.999 3),c in the equation representing the concentration of borneol in g·L-1.Samples from 3 batches of borneol were analyzed by this methods,giving results of total mass concentration of borneol content 0.093,0.097,0.096 g·L-1 respectively.Recovery tests were made by adding different amounts of standard borneol solution to a borneol sample,and values of recovery obtained were from 93.3% to 98.5%.