Article

Protein-Protected Au Clusters as a New Class of Nanoscale Biosensor for Label-Free Fluorescence Detection of Proteases

The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA 30332, USA.
Small (Impact Factor: 7.51). 12/2012; 8(24):3769-3773. DOI: 10.1002/smll.201201983
Source: PubMed

ABSTRACT Destruction for detection: Protein-protected Au clusters are exploited as nanoscale sensors for label-free fluorescence detection of proteases with high sensitivity. The detection mechanism is based on degradation of the protein shell by a protease, allowing the O(2) from ambient air to penetrate through and quench the fluorescence from the Au cluster.

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