A thermo/pH dual-stimuli-responsive drug delivery system (DDS) based on polymer coated mesoporous silica nanostructures (MSNs) is developed for facilitating chemotherapy and photothermal therapy. Thermo/pH-responsive polymer, poly((N-isopropylacrylamide, NIPAM)-co-methacrylic acid, MA), is grafted onto MSNs by in situ polymerization, followed by loading a chemotherapeutic drug (doxorubicin hydrochloride, DOX) and a near-infrared-absorbing phototherapeutic agent (indocyanine green, ICG) to construct the intelligent drug delivery system, shortly as [email protected](NIPAM-co-MA). At NIR irradiation, the photothermal conversion capability of ICG raises the temperature of the DDS and opens the gatekeeper by shrinkage of the copolymer p(NIPAM-co-MA), which triggers controlled release of DOX at an elevated temperature. On the other hand, drug release is also realized at pH 5.3, a characteristic pH value in cancer cell microenvironment, at which it not only causes the shrinkage of the pH-sensitive polymeric moiety of methacrylic acid in [email protected](NIPAM-co-MA) but also deteriorates electrostatic interaction of DOX molecules in the mesoporous channel by protonation of silanols. In addition, ICG further ensures photothermal therapy (PTT) and photodynamic therapy (PDT). The cytotoxicity assay of HeLa cells shows obvious synergistic effect by demonstrating that the combined use of DOX and ICG is more effective in killing HeLa cells than free DOX and ICG. The endocytosis of the drug is monitored by cell imaging.

基于聚合物包被的介孔二氧化硅纳米结构（MSN）的热/ pH双刺激响应药物递送系统（DDS）被开发用于促进化学疗法和光热疗法。热/ pH响应聚合物，聚（（N-异丙基，NIPAM） -共-甲基丙烯酸，MA），通过原位聚合接枝到的MSN，随后加载化疗药物（多柔比星盐酸盐，DOX）和一个近红外吸收光疗剂（吲哚菁绿，ICG）构建智能药物输送系统，简称为[电子邮件保护]（NIPAM- co -MA）。在NIR照射下，ICG的光热转化能力会提高DDS的温度，并通过收缩共聚物p（NIPAM- co-MA），这会触发高温下DOX的受控释放。另一方面，在癌细胞微环境中的特征pH值pH 5.3处也实现了药物释放，在此条件下，它不仅导致[电子邮件保护]（NIPAM- co -MA），但也会由于硅烷醇的质子化而破坏中孔通道中DOX分子的静电相互作用。此外，ICG还确保了光热疗法（PTT）和光动力疗法（PDT）。通过证明DOX和ICG的组合使用比游离DOX和ICG的杀伤HeLa细胞更有效，HeLa细胞的细胞毒性试验显示出明显的协同作用。通过细胞成像监测药物的内吞作用。