Production of polyaniline biosensors modified with conductive polymer composites

Polyaniline biosensors modified with gold nanoparticles which are proper for clinical diagnosis and in laboratories to diagnose cancer were produced by Iranian researchers in Sharif University of Technology. "At first, polyaniline film and gold nanoparticles were grown through electrochemical methods on the graphite surface of printing electrode. Electrodes modified with polyaniline and gold nanoparticles were coated by a monolayer of 17-mer thiol-tethered DNA probe and 6-mercapto-1-hexanol (MCH). Then, due to the strong interaction of streptavidin and biotin, the enzyme containing streptavidin is attached to the biotinylated monolayer of olioligonucleotide that has been attached to the DNA molecule on the surface," Dr. Reihaneh Sadat Saberi, PhD in analytical chemistry from Sharif University of Technology, stated about the research. She pointed to the precise measures undertaken in the research, and said, "Since the appropriate and homogenous distribution of gold nanoparticles on the biosensor surface is important in the performance of the biosensor, a bed of polyaniline was firstly polymerized on the carbon surface of the electrode. Then, gold nanoparticles were added to the prepared bed in order to obtain a homogenous distribution." The biosensor has desirable selectivity and repeatability. Therefore, the modified electrode can be used in the stabilization of phosphatase enzyme as well as in the stabilization of other biological materials. In addition, the biosensor can be used in clinical diagnosis and in the laboratories to diagnose cancer in order to detect cancer tissues. Results of the research have been published in Electroanalysis on 22 April 2013.