Rapid Analysis of Trace Nickel in Hydrogenated Cottonseed Oil by Microwave Digestion Prior to Its Inductively Coupled Plasma Mass Spectrometry Determination

A microwave-assisted digestion procedure for the analysis of trace nickel in hydrogenated cottonseed oil prior to its determination by inductively coupled plasma mass spectrometry was constructed for the first time. The proposed microwave-assisted digestion avoided tarnishing of sample in the process of sample pretreatment and reduced the cycle of analysis. The programs of microwave digestion and the parameters of inductively coupled plasma mass spectrometry were optimized. The accuracy of the proposed method was investigated by analyzing real samples. The results were compared with the ones by pressurized-PTFE-bomb acid digestion and ones by United States Pharmacopeia 28 (USP28) method. This method served as a relatively quick matrix destruction technique compared with other present methods for the quantization of metals in oil.