Askes Sven H C, Leeuwenburgh Vincent C, Pomp Wim, Arjmandi-Tash Hadi, Tanase Stefania, Schmidt Thomas, Bonnet Sylvestre
Leiden Institute of Chemistry and Leiden Institute of Physics, Leiden University , 2300 RA Leiden, The Netherlands.
Van 't Hoff Institute for Molecular Sciences, University of Amsterdam , 1090 GS Amsterdam, The Netherlands.
ACS Biomater Sci Eng. 2017 Mar 13;3(3):322-334. doi: 10.1021/acsbiomaterials.6b00678. Epub 2017 Jan 17.
Light upconversion by triplet-triplet annihilation (TTA-UC) in nanoparticles has received considerable attention for bioimaging and light activation of prodrugs. However, the mechanism of TTA-UC is inherently sensitive for quenching by molecular oxygen. A potential oxygen protection strategy is the coating of TTA-UC nanoparticles with a layer of oxygen-impermeable material. In this work, we explore if (organo)silica can fulfill this protecting role. Three synthesis routes are described for preparing water-dispersible (organo)silica-coated red-to-blue upconverting liposomes. Their upconversion properties are investigated in solution and in A549 lung carcinoma cells. Although it was found that the silica offered no protection from oxygen in solution and after uptake in A549 cancer cells, upon drying of the silica-coated liposome dispersion in an excess of (organo)silica precursor, interesting liposome-silica nanocomposite materials were obtained that were capable of generating blue light upon red light excitation in air.
纳米颗粒中通过三重态-三重态湮灭实现的光上转换（TTA-UC）在生物成像和前药的光激活方面受到了广泛关注。然而，TTA-UC的机制对分子氧猝灭具有内在敏感性。一种潜在的氧保护策略是用一层不透氧材料包覆TTA-UC纳米颗粒。在这项工作中，我们探究了（有机）二氧化硅是否能起到这种保护作用。描述了三种制备水分散性（有机）二氧化硅包覆的红到蓝上转换脂质体的合成路线。在溶液和A549肺癌细胞中研究了它们的上转换特性。尽管发现二氧化硅在溶液中以及被A549癌细胞摄取后都不能提供氧保护，但在过量（有机）二氧化硅前体中干燥二氧化硅包覆的脂质体分散体后，获得了有趣的脂质体-二氧化硅纳米复合材料，它们在空气中用红光激发时能够产生蓝光。
