Synthesis and characterization of NIR-responsive Aurod@pNIPAAm-PEGMA nanogels as vehicles for delivery of photodynamic therapy agents
1 Department of Biomaterials, Research Center of Biomedical Engineering, College of Materials, Xiamen University, Xiamen 361005, China
2 State Key Laboratory for Physical Chemistry of Solid Surfaces, Xiamen University, Xiamen 361005, China
3 Neurosurgical Department of Affiliated Zhongshan Hospital, Xiamen University, Xiamen 361004, China
4 College of Medicine, Xiamen University, Xiamen 361005, China
Nanoscale Research Letters 2013, 8:4 doi:10.1186/1556-276X-8-4Published: 2 January 2013
A near-infrared (NIR)-responsive Aurod@pNIPAAm-PEGMA nanogel was synthesized in two steps, growing a PEGMA monolayer on the surface of gold nanorods (AuNRs), followed by in situ polymerization and cross-linking of N-iso-propylacrylamide (NIPAAm) and poly-(ethylene glycol)-methacrylate (PEGMA). The AuNRs and Aurod@pNIPAAm-PEGMA nanogel were characterized by UV–vis spectroscopy, Raman spectroscopy, Fourier transform infrared spectroscopy, and transmission electron microscopy, respectively. The lower critical solution temperature of the Aurod@pNIPAAm-PEGMA nanogel could be tuned by changing the molar ratio of NIPAAm/PEGMA. The NIR-mediated drug release behavior of the Aurod@pNIPAAm-PEGMA nanogel was studied with zinc phthalocyanines (ZnPc4) as a drug model. It was also demonstrated that the loaded ZnPc4 could keep the capability of generating singlet oxygen, and the in vitro study showed a great photodynamic therapy (PDT) effect on Hela cells. It thus indicated the potential of this Aurod@pNIPAAm-PEGMA nanogel for application as a drug carrier in PDT, which might make contributions to oncotherapy.