Hardware design of portable potentiostat for on-site covid-19 detection

Abstract

Global pandemic COVID-19 was a massive issue in the early part of the decade and made worse with the emergence of various mutations. There are various testing methods to detect the COVID-19. Antigen test kits have low sensitivity in detecting asymptomatic patients. Although PCR test kits are very accurate, it needs to be performed in the laboratory by trained laboratory workers. Alternative detection techniques are electrochemical detection which have high accuracy comparable to PCR. Portable potentiostat was proposed as a point-of-care device for on-site screening of COVID-19, which would improve accessibility, accuracy, and reduce the overall cost of virus detection. The developed portable potentiostat, NACOTS, had been designed with cyclic voltammetry, differential pulse voltammetry, and electrochemical impedance spectroscopy capabilities. NACOTS had been benchmarked against commercialized potentiostat. The on-site diagnosis of COVID-19 had been done using the designed NACOTS hardware. NACOTS printed circuit board development from early Alpha development until the final revision had been shown. Comparison of NACOTS Beta revision was done against PGSTAT302N Autolab and µStat-i 400 DropSens to evaluate the reliability and stability. The result showed similar results across three potentiostats. The final version of NACOTS was benchmarked against Sensit and Pico Development Kit and showed similar results across all potentiostats. On-site testing has been conducted on two occasions. The first on-site test managed to differentiate between the positive and negative samples. The UITM team has performed clinical testing on 148 COVID-19 samples on RT-PCR and NACOTS. Developed potentiostats with COVID-19 detection capabilities have been benchmarked against NACOTS. NACOTS have the edge in terms of having an incubation chamber for the LAMP process, fast detection time, which is less than a minute, as well as the number of samples that were being tested through the clinical test. NACOTS have been tested on 148 samples, when compared to the benchmarked papers which were tested on less than 14 samples.