Investigation of the most effective cotton digestion procedure

Three digestion procedures have been tested for cotton digestion in order to determine major, minor and trace elements by inductively coupled plasma atomic emission spectrometry. Homogenized samples were subjected to dry ashing, open-vessel digestion and microwave digestion and analyzed for presence of 28 elements. The best recoveries of all elements were detected after microwave digestion procedure. Dry ashing was the best method for determination of As, K, Mg, Mn and Na, while open-vessel digestion for Al, Be, Ca and Sb. For the determination of Cd and Co microwave digestion procedure achieved the highest recoveries. The accuracy of digestion methods was estimated by analysis of a certified reference material. Very good agreement within the certified and experimental values was found for the majority of the elements investigated.