Switchable fluorescence of gold nanoclusters for probing the activity of alkaline phosphatase and its application in immunoassay.
In this work, a novel strategy for modulating the fluorescence of gold nanoclusters (Au NCs) is developed. The fluorescence of bovine serum albumin (BSA) protected Au NCs is firstly quenched by KMnO4 and then restored by ascorbic acid (AA) due to the deterioration/restoration of the surface structure. Based on which, a novel "switch-on" fluorescent assay for probing the activity of alkaline phosphatase (ALP) is developed with a detection limit as low as 0.002 U/L. In addition, this testing protocol is also expanded to the detection of the inhibitor of ALP and mouse IgG (as a model), the detection limits are 15 ng/mL for the inhibitor of 2,4-Dichlorophenoxyacetic acid (2,4-DA) and 1.5 pg/mL for mouse IgG. The present method paves a new way to develop convenient, sensitive, and selective metal NCs-based fluorescent "turn-on" probes with promising applications in versatile biosensing.
The Key Laboratory of Food Colloids and Biotechnology, Ministry of Education, School of Chemical and Material Engineering, Jiangnan University, Wuxi 214122, Jiangsu, PR China.
Xue-Lian
XL
Hu
The Key Laboratory of Food Colloids and Biotechnology, Ministry of Education, School of Chemical and Material Engineering, Jiangnan University, Wuxi 214122, Jiangsu, PR China.
Xiu-Ming
XM
Wu
The Key Laboratory of Food Colloids and Biotechnology, Ministry of Education, School of Chemical and Material Engineering, Jiangnan University, Wuxi 214122, Jiangsu, PR China.
Xin
X
Fang
The Key Laboratory of Food Colloids and Biotechnology, Ministry of Education, School of Chemical and Material Engineering, Jiangnan University, Wuxi 214122, Jiangsu, PR China.
Zai-Jun
ZJ
Li
The Key Laboratory of Food Colloids and Biotechnology, Ministry of Education, School of Chemical and Material Engineering, Jiangnan University, Wuxi 214122, Jiangsu, PR China. Electronic address: glwang@jiangnan.edu.cn.
Guang-Li
GL
Wang
D000469:Alkaline Phosphatase / Q000032:analysis* / Q000737:chemistry; D004789:Enzyme Activation; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006046:Gold / Q000737:chemistry*; D007118:Immunoassay / Q000295:instrumentation*; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D015336:Molecular Probe Techniques / Q000295:instrumentation*; D015335:Molecular Probes / Q000737:chemistry; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013050:Spectrometry, Fluorescence / Q000295:instrumentation*
D015335:Molecular Probes; D006046:Gold; D000469:Alkaline Phosphatase
Alkaline phosphatase; Fluorescent biosensing; Gold nanoclusters; Immunoassay