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Updated: Oct 3, 2026

Fabrication of Electrochemical-DNA Biosensors for the Reagentless Detection of Nucleic Acids, Proteins and Small Molecules
Published on: June 1, 2011
Non-chromogenic peptide substrates for detection of enzymes by means of capacitance changes at metal electrodes
H Arwin1, E Agner, I Lundström
1Department of Physics and Measurement Technology, Linköping Institute of Technology, Sweden.
Abstract:
A new type of substrate for enzyme detection has been developed. The substrate is non-chromogenic and is used in an assay method based on electrode adsorption. The rate of change in the electric capacitance of the electrode is monitored and taken as a measure of the substrate adsorption. Substrate adsorption is in turn proportional to substrate bulk concentration and thus subject to changes by enzymes. The new substrate introduces a new concept in enzyme detection: as it is non-chromogenic it may contain appropriate amino acids on both sides of the bond subject to enzymatic cleavage.
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