Zhang Zhen, Zhang Xiao-Lian, Li Bin
School of Chemistry and Chemical Engineering, Gannan Normal University, Ganzhou 341000, China.
Changchun Institute of Optics, Fine Mechanics and Physics, University of Chinese Academy of Sciences, Changchun 130033, China.
Materials (Basel). 2021 Jun 30;14(13):3660. doi: 10.3390/ma14133660.
Photodynamic therapy (PDT) has been reported as a possible pathway for the treatment of tumors. The exploration for promising PDT systems thus attracts continuous research efforts. This work focused on an ordered core-shell structure encapsulated by mesoporous SiO with the upconverting emission property following a surfactant-assisted sol-gel technique. The mesoporous silica shell possessed a high surface area-to-volume ratio and uniform distribution in pore size, favoring photosensitizer (rose bengal) loading. Simultaneously, upconverting nanocrystals were synthesized and used as the core. After modification via hydrophobic silica, the hydrophobic upconverting nanocrystals became hydrophilic ones. Under near-infrared (NIR) light irradiation, the nanomaterials exhibited strong green upconverting luminescence so that rose bengal could be excited to produce singlet oxygen. The photodynamic therapy (PDT) feature was evaluated using a O fluorescent indicator. It was found that this core-shell structure generates O efficiently. The novelty of this core-shell structure was the combination of upconverting nanocrystals with a mesoporous SiO shell so that photosensitizer rose bengal could be effectively adsorbed in the SiO shell and then excited by the upconverting core.
光动力疗法（PDT）已被报道为一种治疗肿瘤的可能途径。因此，对有前景的光动力疗法系统的探索吸引了持续的研究努力。这项工作聚焦于一种由介孔二氧化硅包覆的有序核壳结构，其具有上转换发光特性，采用了表面活性剂辅助的溶胶 - 凝胶技术。介孔二氧化硅壳具有高的表面积与体积比以及孔径的均匀分布，有利于光敏剂（孟加拉玫瑰红）负载。同时，合成了上转换纳米晶体并用作核心。通过疏水二氧化硅改性后，疏水上转换纳米晶体变成了亲水性的。在近红外（NIR）光照射下，纳米材料表现出强烈的绿色上转换发光，从而可以激发孟加拉玫瑰红产生单线态氧。使用一种O荧光指示剂评估了光动力疗法（PDT）特性。发现这种核壳结构能高效产生O。这种核壳结构的新颖之处在于将上转换纳米晶体与介孔二氧化硅壳相结合，使得光敏剂孟加拉玫瑰红能够有效地吸附在二氧化硅壳中，然后被上转换核心激发。
