Experimental design of a microwave-assisted extraction–derivatization method for the analysis of methylmercury

A simultaneous microwave-assisted extraction–derivatization procedure was developed and optimized for methylmercury analysis from biological samples. The analyte was derivatized with sodium tetraphenylborate forming a more hydrophobic compound, methylphenylmercury, which was extractable in toluene. The microwave extraction–derivatization procedure was optimized using experimental design, 25-1 fractional factorial. This chemometrical approach considers main effects as well as interactions of the influential parameters, indicating that temperature and its interaction with NaBPh4 and acetic acid volumes were the variables that significantly affected methylmercury recoveries.