The development of targeted delivery systems can improve the selectivity of cancer drugs. Additionally, a system that promotes the controlled delivery of the drug triggered by an external stimulus in the exact target tissue is highly desirable. Regarding the light stimulus, the NIR window (650–950 nm) is the most suitable due to its higher capacity of penetration in human tissues and less harmful effects on normal cells. In this work, new red-light-responsive nanoparticles for doxorubicin delivery were developed. The nanoparticles were based on cleavable di-block copolymers of poly(ethylene glycol) (PEG) and poly(lactic acid) (PLA) linked by a red-light sensitive segment (1,2-bis(2-hydroxyethylthio)ethylene, BHETE). The PEG-BHETE-PLA copolymers were synthesized under mild conditions and exhibited a narrow polydispersity. The nanoparticles presented a size between 53 and 133 nm, with a doxorubicin loading capacity between 1.2 and 4.4 wt%. Release study of the encapsulated doxorubicin confirms the light-triggered nanoparticle disassembly process. In vitro cytotoxicity tests in MCF7 cell line, for the light-triggered nanoparticles, showed a decrease in cancer cells’ viability higher than 25% compared to non-irradiated cells. Due to the promising results obtained with the light-sensitive PEG-BHETE-PLA nanoparticles, these materials have great potential to be used in drug delivery systems for cancer therapy.

靶向递送系统的开发可以提高抗癌药物的选择性。另外，非常需要一种系统，该系统促进外部刺激在精确的靶组织中触发药物的受控递送。关于光刺激，近红外窗口（650–950 nm）最适合，因为它在人体组织中的穿透能力更高，对正常细胞的危害也较小。在这项工作中，开发了用于阿霉素递送的新的红光响应纳米颗粒。纳米颗粒基于通过红光敏感链段连接的聚乙二醇（PEG）和聚乳酸（PLA）的可裂解二嵌段共聚物（1,2-双（2-羟乙硫基）乙烯，BHETE ）。PEG-BHETE-PLA共聚物是在温和的条件下合成的，表现出较窄的多分散性。纳米颗粒的尺寸在53至133nm之间，阿霉素的负载量在1.2至4.4wt％之间。封装的阿霉素的释放研究证实了光触发纳米颗粒的分解过程。在MCF7细胞系中对光触发的纳米粒子进行的体外细胞毒性测试显示，与未辐照的细胞相比，癌细胞的活力降低幅度超过25％。由于用光敏PEG-BHETE-PLA纳米颗粒获得了可喜的结果，这些材料在用于癌症治疗的药物输送系统中具有巨大的潜力。