This communication describes a novel method for detecting of matrix metalloproteinase-7 activity using a peptide substrate labeled with a ferrocene reporter. The substrate serves as a selective ‘electrochemical proteolytic beacon’ (EPB) for this metalloproteinase. The EPB is immobilized on a gold electrode surface to enable ‘on-off’ electrochemical signaling capability for uncleaved and cleaved events. The EPB is efficiently and selectively cleaved by MMP-7 as measured by the rate of decrease in redox current of ferrocene. Direct transduction of a signal corresponding to peptide cleavage events into an electronic signal thus provides a simple, sensitive route for detecting the MMP activity. The new method allows for identification of the activity of MMP-7 in concentrations as low as 3.4 pM. The concept can be extended to design multiple peptide substrate labeled with different electroactive reporters for assaying multiple MMPs activities.
Revised: June 29, 2009 |
Published: September 27, 2006
Citation
Liu G., J. Wang, D.S. Wunschel, and Y. Lin. 2006.Electrochemical Proteolytic Beacon for Detection of Matrix Metalloproteinase Activities.Journal of the American Chemical Society 128, no. 38:12382-12383.PNNL-SA-50156.doi:10.1021/ja0626638