Key Laboratory for Ultrafine Materials of Ministry of Education, East China University of Science and Technology, Shanghai, 200237, China.
Commonwealth Scientific and Industrial Research Organisation Manufacturing, Research Way Clayton VIC 3168, Private Bag 10, Clayton South, VIC, 3169, Australia.
Small. 2018 Dec;14(51):e1803156. doi: 10.1002/smll.201803156. Epub 2018 Nov 16.
Despite their impressive optical properties, lead halide perovskite quantum dots (PQDs) have not realized their potential, especially in bioimaging applications, as they suffer from poor moisture and thermal stability, solvent incompatibility, and significant toxicity. Here, a spray-assisted coil-globule transition method for encapsulating CsPbBr (CPB) PQDs into poly(methyl methacrylate) (PMMA) polymer nanospheres is reported. Polyvinylpyrrolidone-capped CPB PQDs are synthesized via the ligand assisted reprecipitation method in dichloromethane. After dissolving PMMA, the above precursor solution is sprayed into petroleum ether under high pressure N . High-pressure nebulization restricts the interactions between PMMA polymer chains, resulting in the formation of ≈112 nm nanoscale composite spheres after a coil-globule transition. The CPB@PMMA nanospheres not only possess 73% quantum yields but retain 81% of fluorescence intensity after the exposure to water for over 80 days. Due to their confined size and biocompatible encapsulation, they are readily available for cellular uptake and exhibit no toxicity on live HeLa cells. Furthermore, the PMMA surface allows for functional surface modification, carrying the possibility of targeting specific biological species and processes.
尽管卤化铅钙钛矿量子点（PQDs）具有令人印象深刻的光学性能，但它们尚未发挥其潜力，特别是在生物成像应用中，因为它们存在耐湿性和热稳定性差、溶剂不兼容性以及显著毒性等问题。在这里，我们报告了一种喷雾辅助的螺旋-球转变方法，用于将 CsPbBr（CPB）量子点封装到聚甲基丙烯酸甲酯（PMMA）聚合物纳米球中。通过在二氯甲烷中使用配体辅助再沉淀法合成了聚乙烯基吡咯烷酮封端的 CPB PQDs。将 PMMA 溶解后，将上述前驱体溶液在高压 N 下喷入石油醚中。高压雾化限制了 PMMA 聚合物链之间的相互作用，从而在螺旋-球转变后形成约 112nm 的纳米级复合球体。CPB@PMMA 纳米球不仅具有 73%的量子产率，而且在暴露于水中超过 80 天后仍保留 81%的荧光强度。由于其受限的尺寸和生物相容性的封装，它们易于被细胞摄取，并且在活 HeLa 细胞上没有毒性。此外，PMMA 表面允许进行功能表面改性，具有针对特定生物物种和过程的靶向可能性。
