Institut Lumière Matière, UMR5306, Université Claude Bernard Lyon1-CNRS, Université de Lyon, 69622, Villeurbanne Cedex, France.
Nantes Université, CNRS, US2B, UMR 6286, 44000, Nantes, France.
Chemistry. 2022 Jul 11;28(39):e202200570. doi: 10.1002/chem.202200570. Epub 2022 Jun 15.
Atomically precise gold nanoclusters are a fascinating class of nanomaterials that exhibit molecule-like properties and have outstanding photoluminescence (PL). Their ultrasmall size, molecular chemistry, and biocompatibility make them extremely appealing for selective biomolecule labeling in investigations of biological mechanisms at the cellular and anatomical levels. In this work, we report a simple route to incorporate a preformed Au nanocluster into a model bovine serum albumin (BSA) protein. A new approach combining small-angle X-ray scattering and molecular modeling provides a clear localization of a single Au within the protein to a cysteine residue on the gold nanocluster surface. Attaching Au to BSA strikingly modifies the PL properties with enhancement and a redshift in the second near-infrared (NIR-II) window. This study paves the way to conrol the design of selective sensitive probes in biomolecules through a ligand-based strategy to enable the optical detection of biomolecules in a cellular environment by live imaging.
原子精确的金纳米团簇是一类引人入胜的纳米材料，具有类似分子的性质和出色的光致发光（PL）。它们的超小尺寸、分子化学和生物相容性使它们在细胞和解剖水平的生物机制研究中，对于选择性生物分子标记具有极大的吸引力。在这项工作中，我们报告了一种将预形成的 Au 纳米团簇掺入到模型牛血清白蛋白（BSA）蛋白中的简单方法。一种结合小角 X 射线散射和分子建模的新方法，清晰地将单个 Au 定位在蛋白质内，位于 Au 纳米团簇表面的半胱氨酸残基上。将 Au 附着到 BSA 上，显著地改变了 PL 性质，在第二个近红外（NIR-II）窗口中增强和红移。这项研究为通过基于配体的策略来控制生物分子中选择性敏感探针的设计铺平了道路，从而能够通过活细胞成像实现对生物分子的光学检测。
