It is of great significance to construct multifunctional nanosystems for simultaneous imaging and therapy of cancer cells. Herein, PEGylated chitosan nanoparticles with embedded bismuth sulfide were facilely fabricated via reverse-microemulsion method for fluorescent imaging and photothermal therapy of HepG2 cells. The obtained BSA-Bi₂S₃-CG-PEG nanospheres revealed dual-wavelength fluorescence, which were spectrally isolated from the bioautofluorescence. Moreover, they demonstrated remarkable photothermal conversion efficiency and stability. Importantly, these small BSA-Bi₂S₃-CG-PEG nanoparticles shown a zeta potential of + 42.3 mV, which could rapidly get into HepG2 cells and locate in the cytoplasm and nuclei of cells. Based on their excellent photothermal effect and high cellular uptake, BSA-Bi₂S₃-CG-PEG nanoparticles could efficiently kill HepG2 cells under an 808 nm laser irradiation. This construction strategy can be used for preparation of fluorescent chitosan nanoparticles with other therapeutic agents embedded, which would provide a versatile platform for dual-wavelength fluorescent imaging guided therapy of cancer.

构建多功能纳米系统用于癌细胞的同时成像和治疗具有重要意义。在此，通过反向微乳化方法，可以方便地制备具有嵌入的硫化铋的聚乙二醇化壳聚糖纳米颗粒，用于HepG2细胞的荧光成像和光热疗法。所获得的BSA-Bi ₂ S ₃ -CG-PEG纳米球显示出双波长荧光，其从生物自发荧光光谱分离。而且，它们表现出了显着的光热转化效率和稳定性。重要的是，这些小BSA-Bi ₂ S ₃-CG-PEG纳米颗粒的Zeta电位为+ 42.3 mV，可以迅速进入HepG2细胞并位于细胞质和细胞核中。BSA-Bi ₂ S ₃ -CG-PEG纳米粒子具有出色的光热效应和较高的细胞摄取能力，因此可以在808 nm激光照射下有效杀死HepG2细胞。该构建策略可用于制备嵌入了其他治疗剂的荧光壳聚糖纳米颗粒，这将为癌症的双波长荧光成像引导疗法提供多功能平台。