A label-free, sensitive and simple method to detect protein kinase based on the selective aggregation of phosphorylated peptide-gold nanoclusters (peptide-AuNCs) triggered by Zr(4+) ion coordination is developed. The AuNCs were synthesized by peptide without any strong reducing agents, which prevent peptides from being disrupted. Under optimal conditions, a linear relationship between the decreased PL intensity of peptide-AuNCs and the concentration of casein kinase II (CK2) in the range of 0.08-2.0 unit mL(-1) with a detection limit of 0.027 unit mL(-1) (3σ) was obtained. The feasibility of this AuNCs-based sensor was further demonstrated by the assessment of kinase inhibition by ellagic acid, 5,6-dichlorobenzimidazole-1-β-D-ribofuranoside, emodin, and quercetin in human serum. As expected, the PL intensity increased with increasing inhibitor efficiency in the presence of inhibitors. The IC50 value (inhibitor concentration producing 50

作者：Wei, Song；Ying, Wang；Ru-Ping, Liang；Li, Zhang；Jian-Ding, Qiu

来源：Biosensors & bioelectronics 2015 年 64卷