To explore the application of photoremovable protecting groups (PPGs) in the field of combination chemotherapy, we designed and synthesized a photoresponsive hybrid prodrug 4 that bearing both doxorubicin (DOX) and combretastatin A4 (CA4). Light triggered drug release investigation found that DOX release was mainly accomplished by 405 nm light while CA4 release was mainly triggered by 365 nm light, i.e., prodrug 4 exhibited a quasi-sequential release behavior when a sequential light irradiation strategy was applied. Cell viability evaluation confirmed the increased cytotoxicity of prodrug 4 compared with individual drugs towards MDA-MB-231cells, indicating that a synergistic effect was achieved.

中文翻译：

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光响应性阿霉素/ combretastatin A4杂合前药的合成和表征。

为了探索光可去除保护基（PPGs）在联合化疗领域的应用，我们设计并合成了同时具有阿霉素（DOX）和康维他汀A4（CA4）的光敏杂交前药4。光触发药物释放研究发现，DOX释放主要由405 nm光完成，而CA4释放主要由365 nm光触发，即，当应用顺序光照射策略时，前药4表现出准顺序释放行为。细胞活力评估证实，与个别药物相比，前药4对MDA-MB-231细胞的细胞毒性增加，表明达到了协同作用。