Au-based protein nanoclusters (PNCs) represent an emerging class of fluorescence probes that are inherently biocompatible and combine the functionality of proteins and optical properties of Au nanoclusters. Here we report on a methodology to create conjugated Au PNCs using amino acid coupling strategies from a series of common laboratory proteins. We discover that the host protein and the specific conjugation chemistry has a profound influence on the resulting fluorescence properties. Synchrotron analyses showcase local Au NC aggeration upon PNC conjugation, which causes local environment changes to invoke differences in fluorscence properties. The observed aggeration does not give rise to plasmonic properties nor signifigant fluorescence quenching, strongly indicating the PNCs are still in a near-native cluster state. Our methodology and findings here could open new pathways for tuning PNC fluorescence properties in a rational fashion, having a potential impact in host of biomedical and sensing applications.

基于金的蛋白质纳米团簇（PNC）代表了新兴的一类荧光探针，这些探针本质上具有生物相容性，并且结合了蛋白质的功能和金纳米团簇的光学特性。在这里，我们报告了一种使用一系列常见实验室蛋白的氨基酸偶联策略创建共轭金PNC的方法。我们发现宿主蛋白和特定的共轭化学对产生的荧光性质有深远的影响。同步加速器分析显示，在PNC共轭时，局部Au NC夸张，这导致局部环境变化引起荧光性质的差异。观察到的夸张不会引起等离激元性质或显着的荧光猝灭，强烈表明PNC仍处于近天然簇状态。