Detection of Trace Levels of Lead in Aqueous Liquids Using Extractive Electrospray Ionization Tandem Mass Spectrometry

摘要

In EESI-MS, our data confirmed the existence of primary EDTA ions generated by the ESI channel which then intersected the neutral sample plume to generate anions of EDTA-Pb complexes. In addition, we used EESI-MS~n for the fast detection of trace levels of lead in aqueous liquids including mineral water, lake water, tap water, energy drink, soft drink, beer, orange juice, and tea. The LOD was estimated to be at the femtogram-level for lead in these beverages, which is much lower than the corresponding safety limits. The linear dynamic range was higher than 2 orders of magnitude (ppt~ppb). A single sample analysis was completed within 2 min, with relatively small RSDs. Our experimental data demonstrated that EESI-MS is a useful tool for the fast detection of lead in complex solutions, and EESI-MS showed promise for fast screening of lead-contaminated aqueous samples.