Direct Determination of Chromium in Biological Materials by Solid-Sampling Atomic Absorption Spectrometry: Application of Three-Point Estimation-Standard Addition Method

Abstract

A new method of preparing calibration graphs (three-point estimation-standard addition method) is Proposed for the direct determination of chromium at parts per million or sub-parts per million in powdered biological samples by graphite furnace-atomic absorption spectrometry with a solid-sampling technique using a graphite miniature cup. Accurate analytical results for the direct determination of chromium have been obtained by the proposed method, and it was found that the calibration graph prepared by one sample has since been successfully applied to other kinds of biological samples. The analytical results by the proposed method are compared with the analytical results obtained by a conventional calibration curve prepared by using a chromium standard solution and the standard addition method for solid samples proposed by Eames and Matousek (Anal. Chem., 1980, 52, 1248-1251).