Dendrimers have numerous applications in imaging and drug delivery. Designing a dendrimer diagnostic platform with a well-defined structure and controlled drug delivery is a formidable challenge. Here, we design dendritic polymer-platinum conjugates (G5-PEG-Pt) as pH-responsive nanovesicles for imaging-guided platinum drug delivery. The G5-PEG-Pt have a well-defined structure, intrinsically bright fluorescence, and acid-responsive drug release. The pH-responsive G5-PEG-Pt could rapidly release the platinum drug at acidic pH (5.0) than neutral pH (7.4). The G5-PEG-Pt could enter SKOV-3 human ovarian cancer cells by the endocytosis pathway and exhibited comparative cytotoxicity to free cisplatin. By virtue of the prolonged blood circulation time and the enhanced permeability and retention (EPR) effect, a 4.4-fold higher tumor platinum uptake than that of free cisplatin was achieved, potentially enhancing the therapeutic indexes of the platinum drug. Therefore, these pH-responsive platinum and fluorescent dendrimer conjugates are expected to be potent in vivo cancer optical imaging and therapy platforms.

树枝状聚合物在成像和药物输送方面有许多应用。设计具有明确结构和受控药物递送的树状聚合物诊断平台是一项艰巨的挑战。在这里，我们将树枝状聚合物-铂偶联物 (G5-PEG-Pt) 设计为 pH 响应纳米囊泡，用于成像引导的铂药物递送。G5-PEG-Pt 具有明确的结构、本质上明亮的荧光和酸响应药物释放。pH 响应性 G5-PEG-Pt 可以在酸性 pH (5.0) 比中性 pH (7.4) 下快速​​释放铂药物。G5-PEG-Pt 可通过内吞途径进入 SKOV-3 人卵巢癌细胞，并表现出与游离顺铂相当的细胞毒性。凭借延长的血液循环时间和增强的渗透性和滞留性（EPR）效应，4. 实现了比游离顺铂高 4 倍的肿瘤铂摄取，可能提高铂药物的治疗指标。因此，这些 pH 响应性铂和荧光树枝状聚合物偶联物有望成为有效的体内癌症光学成像和治疗平台。