Multielement analysis of human seminal plasma by octopole reaction cell ICP-MS

Abstract

This study describes optimisation and validation processes for the simultaneous determination of Ag, As, B, Ca, Cd, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Mo, Na, Ni, Pb, Se, Sn, and Zn in seminal plasma samples by inductively coupled plasma mass spectrometry (ICP-MS) using an octopole reaction system (ORS) collision/reaction cell. Two sample pre-treatment procedures, i.e. digestion and dilution, were explored and compared with regard to linearity, detection and quantification limits obtained on a real sample, and precision. To verify the accuracy of these methods, serum and urine QC materials were used, while spiked seminal plasma pooled samples were used to assess precision and recovery. Although both pre-treatment methods allowed sensitive and reproducible analyses, the method of simple dilution of seminal plasma 1 + 19 with aqueous solution containing 0.01 mmol L⁻¹ EDTA, 0.004% v/v NH₃, and 0.07% v/v TritonX-100 was chosen due to the reduced time of analysis and risks of sample contamination. The proposed method was applied for the simultaneous determination of 20 elements in seminal plasma of 76 adult men with suspected infertility, and the results were compared against recent data from the literature. We investigated the element distribution depending on smoking habits and the results of the comparison between 37 smokers and 39 non-smokers showed significantly higher concentrations of Cd in seminal plasma of smokers and this value depended on the increasing number of cigarettes smoked per day (P = 0.004). In addition, our results are the first to provide data for Ag and B concentrations in human seminal plasma.