Methods for the Determination of Arsenic, Cadmium, Copper, Lead, and Tin in Sucrose, Corn Syrups, and High-Fructose Corn Syrups by Inductively Coupled Plasma Atomic Emission Spectrometry

This paper demonstrates the determination of arsenic, cadmium, copper, lead, and tin in sucrose, corn syrups, and high-fructose corn syrups by inductively coupled plasma atomic emission spectrometry (ICP-AES). Sample digestion by both open vessel/hot plate and closed vessel/microwave techniques is reported. Open vessel digestion was suitable for the simultaneous determination of cadmium, copper, and lead. Average recoveries (five different sample types) for the open vessel procedure were 98%, 88%, and 93% for cadmium, copper, and lead, respectively, at 0.10 μg/g. In contrast, microwave digestion yielded average recoveries (five different sample types) of 92%, 83%, 89%, 85%, and 88%, respectively, for arsenic, cadmium, copper, lead, and tin at 1.0 μg/g. Method detection limits were lower with open vessel digestion versus microwave digestion because of sample volume reduction. Sample introduction included microporous membrane desolvation, which assisted digestion and matrix normalization. Keywords: Trace metal analysis; sweeteners; plasma atomic emission spectrometry