Kim Jae Hyun, Choi Jeongyun, Kim Jiwoo, Kim Joohoon
Department of Chemistry, Research Institute for Basic Sciences, Kyung Hee University, Seoul 02447, Republic of Korea.
Department of Chemistry, Research Institute for Basic Sciences, Kyung Hee University, Seoul 02447, Republic of Korea; KHU-KIST Department of Converging Science and Technology, Kyung Hee University, Seoul 02447, Republic of Korea.
Bioelectrochemistry. 2022 Oct;147:108192. doi: 10.1016/j.bioelechem.2022.108192. Epub 2022 Jun 22.
Au nanoclusters (NCs) are considered a promising electrochemiluminescence (ECL) luminophore with biocompatibility and stability that make it suitable for use in bioelectrochemical investigations. The near-infrared (near-IR) ECL of Au NCs is of particular interest for biological applications. In this study, we report the significantly enhanced near-IR ECL of water-soluble Au NCs stabilized with glutathione, which was induced by treating the Au NCs with piperidine. The piperidine treatment of Au NCs enabled a 16-fold enhancement in the near-IR ECL of the NCs in the presence of triethylamine coreactants in water. Compared to the well-known near-IR ECL of Au NCs stabilized with bovine serum albumin (BSA) as a control, the near-IR ECL emission of the piperidine-treated Au NCs (p-Au NCs) was 8 times that of the BSA-stabilized Au NCs. Detailed control experiments suggested that the enhanced near-IR ECL of p-Au NCs could be attributed not to environmental effects (e.g., pH and chemical interference) and the surface ligand effect, but to the reduction of Au(I)-glutathione to Au(0)-glutathione in the NCs. Importantly, the piperidine treatment was also shown to be applicable to different types of Au NCs, such as well-established Au(SG), for improving the ECL emission of the NCs in the near-IR region.
金纳米团簇（NCs）被认为是一种很有前景的具有生物相容性和稳定性的电化学发光（ECL）发光体，使其适用于生物电化学研究。金纳米团簇的近红外（near-IR）ECL在生物应用中特别受关注。在本研究中，我们报道了用谷胱甘肽稳定的水溶性金纳米团簇的近红外ECL显著增强，这是通过用哌啶处理金纳米团簇诱导的。在水中存在三乙胺共反应剂的情况下，用哌啶处理金纳米团簇可使纳米团簇的近红外ECL增强16倍。与以牛血清白蛋白（BSA）稳定的金纳米团簇作为对照的著名近红外ECL相比，经哌啶处理的金纳米团簇（p-Au NCs）的近红外ECL发射是BSA稳定的金纳米团簇的8倍。详细的对照实验表明，p-Au NCs增强的近红外ECL不归因于环境影响（如pH值和化学干扰）和表面配体效应，而是归因于纳米团簇中Au（I）-谷胱甘肽还原为Au（0）-谷胱甘肽。重要的是，哌啶处理也被证明适用于不同类型的金纳米团簇，如成熟的Au（SG），以改善纳米团簇在近红外区域的ECL发射。
