Facile deposition of continuous gold shells on Tween-20 modified Fe₃O₄ superparticles

A facile method to deposit continuous Au shells on Fe₃O₄ colloidal superparticles was developed by introducing Tween-20 as a surface modification agent to maintain the colloidal stability of the Fe₃O₄ superparticles and provide nucleation and growth sites for the Au shells. The Fe₃O₄-Au core-shell particles showed excellent chemical stability, superparamagnetic properties and efficient photothermal conversion performance under laser irradiation at 808 nm, and were expected to be a useful material for biodetection and cancer therapy.