A dual-functional ferroferric oxide/quantum dots theranostic nanoplatform for fluorescent labeling and photothermal therapy

A biocompatible, nontoxic theranostic nanoplatform consisting of mesoporous silica-coated ferroferric oxide (Fe3O4) and Mn-doped ZnS-ZnS quantum dots has been synthesized via a layer-by-layer method. Transmission electron microscopy, X-ray diffractometer, magnetometry, and fluorophotometer were employed to characterize the nanoplatform. The nanoplatform exhibited excellent superparamagnetic, fluorescent and light adsorption properties. A template method was introduced to form a mesoporous silica structure on the nanoplatform, lowering the mass of the nanoplatform and effectively promoting the absorption of incident light, compared with traditional silica layer. In addition, after endocytosis of the nanoplatform, cancer cells were easily detected under fluorescence microscope because of the excellent fluorescent behavior of quantum dos. Moreover, vitro cell experiments confirmed that nanoplatform possessed perfect photothermal effect to destroy tumor cells under the laser irradition. Therefore, ferroferric oxide/quantum dots nanoplatforms, combined with fluorescent labeling and photothermal therapy for cancer cells, are expected to be a promising biopotential materials in the field of diagnosis and treatment.