Inorganic chemical approaches to pharmacognosy. I. Major and trace elements determination in crude drug samples by energy-dispersive X-ray fluorescence spectrometry.

Abstract

A convenient method requiring only one standard material was developed for the multielemental analysis (20 elements) of crude drug samples by energy-dispersive X-ray fluorescence spectrometry. The analytical method was based on the principle that when a sample powder is shaped into a very thin pellet, the excitation effect of the matrix is negligible, and a correction factor for the matrix absorption effect can be obtained by mathematical treatment. Percentage accuracies are better than ±10%, and detection limits are in the low ppm range for most elements. The present method is suitable for the examination of metal-containing profiles of many crude drug samples because of its ease of application. Several samples were analyzed and each crude drug was found to apparently have a characteristic metal profile.