Theobromine (3,7-dimethylpurine-2,6-dione), is used as vasodilator, a blood vessel widener), bronchodilator, as an aid in urination and as a heart stimulant, asthma and cough. Therefore, it is important to evaluate the biocompatibility of theobromine to ensure the safety of people consuming it. Furthermore, a quick and easy method has been optimized and validated to determine the quantity of heavy metals like V, Co, Ni, Cd, Hg, Pb and As, present in commercial theobromine by using quadrupole inductively coupled plasma mass spectrometry (Q-ICP-MS). The detection limits were between 0.16 and 7.23μg/L and quantification limits were between 1.5 and 60μg/L. The mean recoveries±standard deviations were varied between 83.1±0.5% and 106.7±2.1% and the coefficients of variation were between 0.2% and 3.1%. The method precision, in terms of relative standard deviation, was below 2.23%. The method uncertainty expressed as expanded uncertainty was found to be≤3.6%..

Keywords:Theobromine; Elemental impurities; Class 1 and 2A; Q-ICP-MS; Analytical method validation; Concurrent analysisz