CuInS2 quantum dots@silica near-infrared fluorescent nanoprobe for cell imaging

Abstract

In this paper, near-infrared (NIR) fluorescent CuInS₂ QDs@SiO₂ nanobeads were prepared and used as fluorescent nanoprobes for prostate cancer cells imaging. The core–shell CuInS₂ QDs@SiO₂ nanobeads with controllable particle sizes were synthesized via a reverse microemulsion method. Further surface modifications were performed for grafting amino groups on the surface of the NIR CuInS₂ QDs@SiO₂ nanobeads. For prostate cancer cell imaging, anti-PSCA antibody was conjugated to the NIR CuInS₂ QDs@SiO₂ nanobeads to prepare the anti-PSCA–QDs@SiO₂ nanoprobe. The specific binding of the antibody conjugated CuInS₂ QDs@SiO₂ nanobeads to the surface of human prostate cancer cells (PC-3M) was confirmed by fluorescence microscopy. MTT assay and fluorescence microscopy images showed that the anti-PSCA-conjugated NIR CuInS₂ QDs@SiO₂ nanoprobe was a non-toxic nanoprobe and had high-specificity in cell imaging. The CuInS₂ QDs@SiO₂ nanoprobe as an efficient NIR imaging nanoprobe could be used for target imaging, biological assays and early diagnosis of cancer.