Iranian researchers from Mazandaran University introduced a new DNA genosensor by synthesizing gold nanoparticles through chemical reduction method and producing carbon paste electrodes modified with the synthesized gold nanoparticles. The results of the research can be used in pharmaceutical and medical industries, diagnosis of genetic malfunctions, and clinical diagnosis in hospitals and clinics. Seyedeh Zeinab Moussavi Sani, one of the researchers of the plan, elaborated on the research, and said, “The use of gold nanoparticles in the structure of carbon paste increases the conductivity and the amount of the stabilized target DNA on the surface of the modified electrode. It also increases the electrochemical signal of guanine oxidation on the surface of the carbon paste electrode modified with gold nanoparticles in comparison with the bare carbon paste electrode. It finally results in an increase in the selectivity of the biosensor towards the target DNA and the sensitivity of the method.” Results
showed that the produced biosensors had more desirable selectivity in DNA crossing than complementary DNA in comparison with non-complementary DNA series. “The comparison between the values obtained for the linear range of concentration and detection limit on the surface of biosensors made of bare carbon paste electrodes and carbon paste electrodes modified with gold nanoparticles showed that carbon paste electrodes modified with gold nanoparticles had a wider concentration linear range while they had smaller detection limit. Therefore, we increased the sensitivity of the biosensor by using gold nanoparticles in the structure of carbon paste electrode. Taking into account that DNA concentration is very low at biological media, the production of biosensors that are able to measure low concentrations of DNA is very important,” Moussavi said. Results of the research have been published on 10 June 2013 in Journal of Chinese Chemical Society, vol. 60, issue 6. For more information about the details of the
research, study the full article on pages 650-656 on the same journal.