Voltammetric Detection Of Microcystis Genus Specific-sequence With Disposable Screenprinted Electrode Modified With Gold Nanoparticles

A disposable electrochemical biosensor for detection of DNA sequence related to Microcystis was described. After depositing gold nanoparticles (AuNPs) onto a screen-printed carbon electrode (SPCE) surface by electrodeposition, the DNA probe which is complementary to a specific gene sequence related to Microcystis was immobilized onto the AuNPs modified SPCE via a thiol linker at the 5’ end. On the electrode surface the immobilized single-stranded DNA could undergo hybridization in the solution containing DNA specific-sequence of Microcystis. Using methylene blue as the indicator, DNA immobilization and hybridization were characterized by cyclic voltammetry and differential pulse voltammetry. Parameters, such as the deposition conditions of gold nanopariticle and the preconcentration time of MB, were optimized. In addition, the control experiments with non-complementary and single base mismatch sequences were investigated and results demonstrated the high selectivity of the biosensor.