Preliminary Study of Electrochemical DNA Sensor for Cucumber Mosaic Virus

An electrochemical DNA (EC-DNA) sensor using screen printed gold electrode (SPGE) was developed to detect CMV. Cyclic Voltammetric (CV) analysis was performed to characterize the working gold electrode surface using potassium ferrocyanide. A direct self assemble monolayer (SAM) format was applied. The modification of SPGE surfaces was conducted using 5mM thiol solution. Immobilisation of CMV DNA probe was carried out by activating carboxylic acid groups of thiol monolayer with 20μL of EDC-NHS mixture. Various concentration of CMV DNA probe solution (1ng/μL, 10ng/μL, and 100ng/μL) was applied to the gold surface. The hybridization process was carried out by applying CMV complementary DNA solution on top of CMV DNA probe layer. The DNA hybridization reaction occurred on the electrode surface was then electrochemically measured using CV analysis. The measurements were performed using Autolab potentiostat with NOVA 1.11 software. The significant potential of 0.1V was selected. The oxidation activity was occurred at+ 0.1± 0.02mV and reduction activity was observed at range -ve 0.075± 0.025mV.