Magnetic particles with a particle size of 400 nm were synthesized in one step by hydrothermal method for the detection of Pb2+ in human serum.They were characterized by Zeta potentiometry and single particle inductively coupled plasma mass spectrometry(SP-ICP-MS).The serum samples were pretreated by microwave digestion method,then separated and enriched with Fe3O4 magnetic particles,and finally detected by ICP-MS.Experimental conditions for the separation and enrichment of Pb2+ using Fe3O4 magnetic particles were optimized.The quantitative detection of Pb2+ in serum was successfully achieved at pH 50,using a 400 μL of adsorbent adsorbing for 30 min,and the enrichment factor was 10.The limit of detection(LOD) and the limit of quantitation(LOQ) were 7 ng/L and 23.1 ng/L,respectively.