Plasmon-Mediated Generation of Reactive Oxygen Species from Near-Infrared Light Excited Gold Nanocages for Photodynamic Therapy in Vitro
Plasmon-Mediated Generation of Reactive Oxygen Species from Near-Infrared Light Excited Gold Nanocages for Photodynamic Therapy in Vitro
复制标题
等离激元介导的近红外光激发金纳米笼产生活性氧，用于体外光动力治疗
DOI：
10.1021/nn502325j
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发表时间：
2014-07-01
期刊：
影响因子：
17.1
通讯作者：
Gao, Xueyun
中科院分区：
文献类型：
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作者：
Gao, Liang;Liu, Ru;Gao, Xueyun
我们对金纳米笼（AuNCs）作为内在无机光敏剂在近红外（NIR）单/双光子照射下通过等离子体光化学介导活性氧（ROS）的产生进行了基本分析。我们发现，近红外光激发的热电子转化为ROS或热疗。应用电子自旋共振谱法证实了三种主要自由基的产生，即单线态氧（O-1(2)）、超氧自由基阴离子（O-2（-中心点））和羟基自由基（(OH)- o -中心点）。通过精心设计的三电极体系光电化学实验，证实了辐照AuNCs中存在热电子。可以推测，在AuNCs中激发的表面等离子体首先衰变为热电子，然后产生的热电子通过能量和电子转移模式敏化氧形成ROS。我们还比较了单/双光子辐照下不同表面化学环境下AuNCs的ROS生成效率，验证了与单光子辐照相比，双光子辐照能产生更多的ROS。此外，在体外双光子照射下，ROS可触发线粒体去极化和caspase蛋白上调，从而引发肿瘤细胞凋亡。同时，热疗主要诱导肿瘤细胞坏死。我们的研究结果表明，等离子体介导的ROS和热疗可以很容易地调节，以优化抗癌光疗。
We have performed fundamental assays of gold nanocages (AuNCs) as intrinsic inorganic photosensitizers mediating generation of reactive oxygen species (ROS) by plasmon-enabled photochemistry under near-infrared (NIR) one/two-photon irradiation. We disclosed that NIR light excited hot electrons transform into either ROS or hyperthermia. Electron spin resonance spectroscopy was applied to demonstrate the production of three main radical species, namely, singlet oxygen (O-1(2)), superoxide radical anion (O-2(-center dot)), and hydroxyl radical ((OH)-O-center dot). The existence of hot electrons from irradiated AuNCs was confirmed by a well-designed photoelectrochemical experiment based on a three-electrode system. It could be speculated that surface plasmons excited in AuNCs first decay into hot electrons, and then the generated hot electrons sensitize oxygen to form ROS through energy and electron transfer modes. We also compared AuNCs' ROS generation efficiency in different surface chemical environments under one/two-photon irradiation and verified that, compared with one-photon irradiation, two-photon irradiation could bring about much more ROS. furthermore, in vitro, under two-photon irradiation, ROS can trigger mitochondrial depolarization and caspase protein up-regulation to initiate tumor cell apoptosis. Meanwhile, hyperthermia mainly induces tumor cell necrosis. Our findings suggest that plasmon-mediated ROS and hyperthermia can be facilely regulated for optimized anticancer phototherapy.