Abstract
With the aim of developing compact and sensitive immunoassay devices for point-of-care testing, we studied an electrochemical method by using continuous flow in a microchannel gold-linked electrochemical immunoassay (GLEIA) on a screen-printed carbon electrode. Conventional GLEIA is a useful method to detect low-level antigen in real samples, but it requires a long incubation time (∼1h) and milliliter-order reagent volumes for measurement. In this study, a screen-printed electrode was put into a microfluidic channel to study the microchannel effect on GLEIA. By limiting the diffusion volume during the pre-oxidation to oxidation step of GLEIA, we found that the sensitivity increased. Owing to the continuous flow in a microchannel, the antigen-antibody reaction was accelerated, resulting in a 10 min detection time. It was also effective in reducing the minimum volume of washing buffer required.
