A reference electrode-free electrochemical biosensor for detecting MMP-9 using a concentric electrode device

Matrix Metalloproteinase-9 (MMP-9) as a Cancer Biomarker and MMP-9 Biosensors: Recent Advances

“…In a recent study, researchers produced an electrode-free electrochemical biosensor to detect MMP-9 ( Figure 4 ) [ 119 ]. In this study, a redox reporter labeled peptide with MMP-9 cleavage site was used.…”

“…Methylene blue (MB) was conjugated at the N-terminal of this peptide. This peptide was immobilized on Au electrodes through a thiolate bond at its C-terminal ( Figure 4 ) [ 119 ]. In the presence of MMP-9, the specific substrate peptide of MMP-9 was cleaved by it.…”

Recent Advances in Electrochemical Sensors for the Detection of Biomolecules and Whole Cells

“…Consequently, it is essential to precisely detect its activities and quantities at the cellular level [ 74 ]. Lee et al (2016) reported that the redox reporter MB labeled with the peptide was used to integrate a gold-based biosensor [ 76 ]. Classical lithography and etching processes are defined as production techniques where the working electrode can maintain a continuous potential without the reference electrode [ 105 ].…”

Miniaturisation of a peptide-based electrochemical protease activity sensor using platinum microelectrodes

“…There is extensive literature reported on protease detection using this approach. [13][14][15][16][17][18][19][20][21][22] For example, Liu et al described a method that allowed detection of matrix metalloproteinases (MMPs), whose proteolytic activities have close association with cancer progression, at very low concentrations (with a limit of detection of 3.4 pM). 15 An alternative approach was developed by Lee et al who reported on the reference electrode-free sensing of MMP-9 using the self-gating effect on a concentric electrode system which consisted of an island and enclosing electrode.…”

“…15 An alternative approach was developed by Lee et al who reported on the reference electrode-free sensing of MMP-9 using the self-gating effect on a concentric electrode system which consisted of an island and enclosing electrode. 22 We have previously proposed, produced, characterised and optimised a macroelectrode-based sensor system for the detection of protease activity using a self-assembled monolayer (SAM) on an electrode surface, which was successfully translated to the detection of other proteases such as human neutrophil elastase, allowing clinically relevant measurements of its activity in human blood. 20,23 However, the electrodes used in most of these systems are still macroscopic which leads to limitations with respect to sensor performance as well as their applicability to implantation.…”