Department of Chemical and Biological Engineering, The University of Alabama, Tuscaloosa, AL35487, USA.
Nanoscale. 2014;6(3):1515-24. doi: 10.1039/c3nr06040c.
Protein-encapsulated gold nanoclusters have shown many advantages over other gold nanocluster systems, including green synthesis, biocompatibility, high water solubility, and the ease of further conjugation. In this article, we systematically investigated the effects of the protein size and amino acid content on the formation and fluorescent properties of gold nanoclusters using four model proteins (bovine serum albumin, lysozyme, trypsin, and pepsin). We discovered that the balance of amine and tyrosine/tryptophan containing residues was critical for the nanocluster formation. Protein templates with low cysteine contents caused blue shifts in the fluorescent emissions and difference in fluorescent lifetimes of the gold nanoclusters. Furthermore, the protein size was found to be a critical factor for the photostability and long-term stability of gold nanoclusters. The size of the protein also affected the Au nanocluster behaviour after immobilization.
蛋白包裹的金纳米团簇在许多方面都优于其他金纳米团簇体系，包括绿色合成、生物相容性、高水溶性以及易于进一步缀合。在本文中，我们使用四种模型蛋白（牛血清白蛋白、溶菌酶、胰蛋白酶和胃蛋白酶）系统地研究了蛋白大小和氨基酸含量对金纳米团簇形成和荧光性质的影响。我们发现，胺和含酪氨酸/色氨酸残基的平衡对于纳米团簇的形成至关重要。半胱氨酸含量低的蛋白模板会导致金纳米团簇荧光发射的蓝移和荧光寿命的差异。此外，还发现蛋白大小是金纳米团簇光稳定性和长期稳定性的关键因素。蛋白的大小也会影响金纳米团簇固定化后的行为。
