机械研磨法制备荧光可调碳量子点

Preparation of fluorescence tunable carbon quantum dots by mechanical trituration method

以有机小分子丙酮为前驱体,在碱性条件下,采用机械研磨法制备了蓝绿色荧光碳量子点(carbon quantumdots,CQDs-1),其荧光发射波长为500nm.加入氟化钾(或氯化钾)共同研磨后得到黄色荧光CQDs(CQDs-2,荧光发射波长为560nm),而加入溴化钾(或碘化钾)共同研磨得到红色荧光CQDs(CQDs-3,荧光发射波长为600 nm).通过紫外可见吸收光谱(UV-Vis)和荧光光谱(PL)测定了3种CQDs的光学性质;通过透射电子显微镜(TEM)、原子力显微镜(AFM)、X射线粉末衍射(XRD)和拉曼光谱(Raman)对制得的CQDs进行了形貌及结构表征,并推断了CQDs的形成机理.采用简单的机械研磨法制备的荧光可调CQDs具有低细胞毒性、良好的水溶性和生物兼容性,可进入肿瘤细胞用于细胞成像研究.

Carbon quantum dots （CQDs） which emitted blue-green fluorescence （abbreviated as CQDs- 1） were prepared by grinding organic small molecule acetone under alkaline conditions. Upon adding KF （or KC1） and grinding with acetone, the fluorescence emission peak of CQDs shifts from 500 nm （CQDs- 1） to 560 nm （CQDs-2）. And red fluorescent CQDs-3 with a fluorescence emission peak of 600 nm （CQDs-3） were obtained when KF （or KC1） was changed to KBr （or KI） under the same conditions. UV-Vis absorption spectrum and fluorescence spectrum were used to study their optical properties. And their morphologies and microstructures were characterized by transmission electron microscope （TEM）, atomic force microscope （AFM）, X-ray diffraction （XRD） and Raman spectra. The formation mechanism of CQDs was explored. The results show that CQDs prepared by such simple mechanical trituration method exhibit low cytotoxicity, high water solubility and good biocompatibility, thus they can be used for tumor cell imaging.