Related Experiment Video
Updated: Feb 16, 2026

A Polyaniline-based Sensor of Nucleic Acids
Published on: November 1, 2016
Ultrasensitive electrochemical immunoassay for melanoma cells using mesoporous polyaniline
M U Anu Prathap1, Carlos Iván Rodríguez, Omer Sadak
1Department of Biological Systems Engineering, University of Wisconsin-Madison, 460 H Mall, Madison, WI 53706, USA. guna@wisc.edu.
Abstract:
We report the development of an antibody (anti-MC1R antibody)-functionalized polyaniline nanofibers modified screen-printed electrode capable of efficient electrochemical detection of melanoma cells at levels (1 cell per mL) not readily achieved by other methods. This immunosensor is highly selective in its detection of melanoma cells over normal human cells.
Related Concept Videos
What is an Electrochemical Gradient?
The chemical gradient relies on differences in the abundance of a substance on the outside versus the inside of a cell and flows from areas of high to low ion concentration. In contrast, the electrical gradient revolves around an...
Interfacial Electrochemical Methods: Overview
Electrochemical Gradient and Channel Proteins: An Overview
The electrical gradient: The electrical gradient across cell membranes refers to the difference in electric charge between the inside and outside of a cell. This difference drives the movement of ions towards or away from the cells. For instance, if the inside of the cell is more negatively charged relative to...
Concentration Cells
Consider the following voltaic cell:
Voltaic/Galvanic Cells
Spontaneous redox reactions occur abundantly in nature. The chemical reaction occurring in a disposable AA battery powering our remote controls is one such example of a spontaneous redox reaction. Another example is the immersion of coiled copper wire into an aqueous silver nitrate solution. The reaction shows a gradual, visually impressive color change from colorless to bright blue and the formation of a grey precipitate on the copper wire. In this experiment,...
Cell Potential and Free Energy
Thermodynamics is the branch of physics dealing with the relationship between heat and other forms of energy. In an electrochemical cell, chemical energy is converted into electrical energy.
Thus, a link can be predicted between cell potential, free energy change, and the equilibrium constant for the reaction. Cell potential can also be measured as the oxidant or the reducing strength, and similar acid-base strength measures are reflected in equilibrium...

