Bujňáková Zdenka, Baláž Matej, Dutková Erika, Baláž Peter, Kello Martin, Mojžišová Gabriela, Mojžiš Ján, Vilková Mária, Imrich Ján, Psotka Miroslav
Institute of Geotechnics, Slovak Academy of Sciences, Watsonova 45, 04001 Košice, Slovakia.
Faculty of Medicine, P. J. Šafárik University, Trieda SNP 1, 04011 Košice, Slovakia.
J Colloid Interface Sci. 2017 Jan 15;486:97-111. doi: 10.1016/j.jcis.2016.09.033. Epub 2016 Sep 15.
The wet mechanochemical procedure for the capping of the CdS and CdS/ZnS quantum dot nanocrystals is reported. l-cysteine and polyvinylpyrrolidone (PVP) were used as capping agents. When using l-cysteine, the dissolution of cadmium(II) was almost none for CdS/ZnS nanocrystals. Moreover, prepared CdS- and CdS/ZnS-cysteine nanosuspensions exhibited unimodal particle size distributions with very good stability, which was further supported by the zeta potential measurements. The Fourier-transform infrared (FTIR) and nuclear magnetic resonance (NMR) spectroscopy showed the successful embedment of cysteine into the structure of the nanocrystals. Additionally, the optical properties were examined, and the results showed that the cysteine nanosuspension has promising fluorescence properties. On the other hand, PVP was not determined to be a very suitable capping agent for the present system. In this case, the release of cadmium(II) was higher in comparison to the l-cysteine capped samples. The nanosuspensions were successfully used for in vitro studies on selected cancer cell lines. Using fluorescence microscopy, it was evidenced that the nanocrystals enter the cell and that they can serve as imaging agents in biomedical applications.
报道了用于CdS和CdS/ZnS量子点纳米晶体封端的湿机械化学方法。使用L-半胱氨酸和聚乙烯吡咯烷酮（PVP）作为封端剂。使用L-半胱氨酸时，对于CdS/ZnS纳米晶体，镉（II）的溶解几乎为零。此外，制备的CdS-半胱氨酸和CdS/ZnS-半胱氨酸纳米悬浮液呈现单峰粒度分布，具有非常好的稳定性，zeta电位测量进一步证实了这一点。傅里叶变换红外（FTIR）光谱和核磁共振（NMR）光谱表明半胱氨酸成功嵌入纳米晶体结构中。此外，对光学性质进行了检测，结果表明半胱氨酸纳米悬浮液具有良好的荧光性质。另一方面，PVP被确定不是本系统非常合适的封端剂。在这种情况下，与L-半胱氨酸封端的样品相比，镉（II）的释放更高。纳米悬浮液成功用于对选定癌细胞系的体外研究。使用荧光显微镜证明，纳米晶体进入细胞，并且它们可以在生物医学应用中用作成像剂。
