RESUMO
Metallothionein ( MT) is a low-molecular-weight protein with high inducibility and binding ability with metal ions. Therefore, MT is often regarded as an important biomarker for assessment of heavy metal pollution in water environment. But the traditional process of its enrichment and identification is time-consuming and complicated. Herein, we prepared a core-shell nanoparticle, gold-coated iron oxide nanoparticles ( Fe3O4@Au NPs) . The nanoparticle possessed the advantages such as fast response to magnetic fields and optical properties attributing to Fe3O4and Au nanoparticles separately. Fe3O4@Au nanoparticles were used to enrich MT simply through Au-S interaction, and the purified proteins were determined by matrix assisted laser desorption ionization time-of-flight mass spectrometry ( MALDI-TOF/MS) . The results in this work showed that the Fe3O4@Au nanoparticles could directly enrich MT from complex solutions and the detection limit could be down to 10 fg/mL.