Electrochemical impedance spectroscopy for quantization of matrix Metalloproteinase-14 based on peptides inhibiting its homodimerization and heterodimerization

Abstract

We reported here two novel electrochemical impedance spectroscopy biosensors were developed for the first time for highly sensitive quantification of matrix metalloproteinase-14 (MMP-14) based on binding interaction between hemopexin-like domain (PEX) of MMP-14 (PEX-14) and its inhibitory peptides. Specific inhibitory peptides (IVSC or ISC) inhibiting homodimerization or heterodimerization of MMP-14 was first self assembled on the surface of gold electrode and blocked with 6-mercapto-1-hexanol on a gold electrode surface used as IVSC or ISC modified biosensor, respectively. IVSC modified biosensor can be used for detection of MMP-14 by using the direct IVSC-MMP-14 interaction inhibiting MMP-14 homodimerization as well as ISC modified biosensor for indirect detection of MMP-14 via PEX-14 mediated peptide-MMP-14 binding. The electron transfer resistance (Ret) of biosensor was monitored to measure MMP-14 using Fe(CN)63−/4- as probe. The increase of the Ret of the biosensors are linear with the concentration of MMP-14 in the range from 1 μg L−1 to 10 μg L−1 with detection limit of 0.19 μg L−1 for IVSC modified biosensor and 0.1 ng L−1 to 50 ng L−1 with detection limit of 7 ng L−1 for ISC modified biosensor. This work demonstrates that probing the interaction between peptide inhibitor and PEX of MMPs represents a novel approach to assess MMPs-mediated cancer dissemination.