Thermoresponsive polymers incorporated with photo-absorbing agents have been widely utilized for controlled drug delivery using light as an external stimulus. However, previously developed thermoresponsive drug carriers have disadvantages such as low biocompatibility and implantation failure. In the present study, gold nanorods (GNRs)-encapsulated poly(N-vinyl caprolactam) (PVCL) (GNR-PVCL) microparticles were synthesized by the stop-flow lithography (SFL) method. The SFL method enabled the fabrication of near-infrared (NIR) light-responsive GNR-PVCL microparticles of uniform size, which can allow localized injection. Doxorubicin (DOX) was encapsulated into GNR-PVCL microparticles to achieve NIR light-responsive anticancer therapy. DOX-loaded GNR-PVCL (DOX-GNR-PVCL) microparticles exhibited NIR light-triggered drug release due to the photothermal effect of GNRs, which increases the local temperature above the volume phase transition temperature of GNR-PVCL microparticles. In addition, DOX-GNR-PVCL exhibited controlled DOX release in response to the periodic irradiation of NIR light. Moreover, we demonstrated the efficient intracellular release of DOX upon NIR light exposure, and thus, NIR light-responsive anticancer activity. This study demonstrates that DOX-GNR-PVCL microparticles have significant potential as implantable drug carriers enabling NIR light-triggered drug release.

结合有光吸收剂的热响应性聚合物已被广泛用于利用光作为外部刺激的受控药物递送。然而，先前开发的热响应性药物载体具有诸如低生物相容性和植入失败的缺点。在本研究中，金纳米棒（GNRs）封装的聚N通过停止流式光刻（SFL）方法合成了-乙烯基己内酰胺（PVCL）（GNR-PVCL）微粒。SFL方法使得能够制造出均一尺寸的近红外（NIR）光响应性GNR-PVCL微粒，从而可以进行局部注射。将阿霉素（DOX）封装到GNR-PVCL微粒中，以实现NIR光响应性抗癌治疗。载有DOX的GNR-PVCL（DOX-GNR-PVCL）微粒由于GNRs的光热效应而显示出NIR光触发的药物释放，从而使局部温度升高到GNR-PVCL微粒的体积相变温度以上。另外，DOX-GNR-PVCL响应于NIR光的周期性照射而表现出受控的DOX释放。此外，我们证明了近红外曝光后DOX的有效细胞内释放，因此，NIR光响应性抗癌活性。这项研究表明，DOX-GNR-PVCL微粒作为可植入药物载体具有显着潜力，可实现NIR光触发的药物释放。