Determination of Lead Species in Algae by Capillary Electrophoresis-Inductively Coupled Plasma-Mass Spectrometry

A method of capillary electrophoresis (CE) coupled with inductively coupled plasma-mass spectrometry (ICP-MS) was established to determine lead ion [Pb(II)], trimethyl lead (TML), and triethyl lead (TEL). An extraction technology for lead with different species in algae was proposed and optimized for qualitative and quantitative analyses. Experimental results showed that these three lead compounds could be effectively separated within 20 min by CE-ICP-MS in a buffer solution of 70 mM H3BO3 and 17.5 M Na2B4O7 (pH 8.9). This method had good reproducibility for migration time (relative standard deviation (RSD) < 4%) and peak area (RSD < 5%). On the basis of this, the three lead compounds were detected in the linearity range of 10-200 mu g L-1 with the correlation coefficient over 0.90. The detection limits for Pb(II), TML and TEL (S/N = 3, Pb) were 0.091, 0.023 and 0.030 mu g L-1, respectively. The fractional extraction rate of Pb exceeded 80%, and the recoveries of Pb(II), TML, and TEL in algae samples were 103.6%, 95.7% and 90.6%, respectively. The detection results of lead content in laver and kelp samples showed that Pb in algae mainly existed in the form of Pb(II). Given its simplicity, high efficiency, and low sample consumption, the method could provide technical support for the quality control of marine algae and other marine products.