Microwave-Assisted Synthesis of Cholic Acid-Capped Gold Nanoclusters as Fluorescence-Enhanced Probes for Creatinine Detection

In this study, the cholic acid-capped gold nanoclusters (CC-AuNCs) were prepared via a microwave-assisted approach and were used as a novel fluorescence probe for detection of creatinine. The CC-AuNCs in solution can emit strong green fluorescence under UV light and the fluorescence intensity can increase with creatinine concentration in the solution because of the aggregation of CC-AuNCs. On the basis of these facts, the fluorescence assay for creatinine was developed. The linear working range is 1.0×10−10–1.0×10−7M with a detection limit of 7.54×10−12M according to signal/noise ratio of 3:1. This fluorescence assay for creatinine has a low detection limit, wide linear range and good selectivity. Furthermore, it can be successfully applied to the detection of creatinine in human urine and serum samples. Thus, this CC-AuNC-based fluorescence assay for creatinine might be of great importance in early diagnosis and therapy of kidney disease.