Alternative method for chromium determination in pharmaceutical drugs by HR-CS GF AAS and direct analysis of solid samples

High-resolution continuum source graphite furnace atomic absorption spectrometry (HR-CS GF AAS) was used to develop an analytical method for chromium determination in pharmaceutical drugs through direct analysis of solid samples. The limit of detection and quantification were, respectively, 2.9 μg kg− 1 and 9.7 μg kg− 1 and the characteristic mass was 2.0 pg. Eighteen pharmaceutical drugs and three excipients were analyzed. The encapsulated samples were opened and only its powder content was analyzed; the tablet samples were grinded before the analysis. The results obtained from the direct analysis of the solid samples were in agreement with those found after total digestion of samples using a closed-vessel microwave oven device, with a confidence level of 95%. The Cr concentration obtained for the different capsules and tablets investigated varied between 0.05 and 1.92 mg kg− 1. The proposed method is fast, reliable and simple for routine pharmaceutical analysis.