Direct determination of chromium in gelatine by graphite furnace atomic absorption spectrophotometry

A fast and direct method for the determination of Cr in gelatine using graphite furnace atomic absorption spectrophotometry with Zeeman-effect background correction is described. No sample pre-treatment was necessary, minimizing the risk of contamination. The concentration of chromium in gelatine was directly evaluated applying the standard additions method from a metal spiked gelatine (0.5% m/v) dispersed in 1% v/v nitric acid solution. The heating program was implemented in 68 s. The estimated mean characteristic mass is 3.4 pg Cr for a 15 μl sample. The Cr values determined in gelatine with the proposed procedure are in close agreement with those obtained by employing an acid digestion procedure (r = 0.9987).