Table of Contents
Electrochemical biosensors are devices that detect biological molecules by converting chemical information into an electrical signal. A key aspect of their function is understanding and calculating electrochemical potentials, which influence sensor accuracy and sensitivity.
Basics of Electrochemical Potential
The electrochemical potential is the energy required to move an ion or electron within an electrochemical cell. It combines the chemical potential and the electrical potential, reflecting the driving force for electrochemical reactions.
Measuring Electrochemical Potential in Biosensors
In biosensors, the potential is typically measured using electrodes that detect changes caused by target molecules. The reference electrode provides a stable potential, while the working electrode responds to analyte interactions.
Calculating Electrochemical Potential
The Nernst equation is commonly used to calculate the electrochemical potential:
E = E0 – (RT / nF) * ln([Red]/[Ox])
Where:
- E is the electrode potential
- E0 is the standard electrode potential
- R is the gas constant
- T is temperature in Kelvin
- n is the number of electrons transferred
- F is the Faraday constant
- [Red] and [Ox] are the concentrations of reduced and oxidized forms
By inputting known values, the potential difference can be calculated, aiding in sensor calibration and analysis.