This article reviews optical biosensors and their integration with microfluidic channels. The integrated biosensors have the advantages of higher accuracy and sensitivity because they can simultaneously monitor two or more parameters. They can further incorporate many functionalities such as electrical control and signal readout monolithically in a single semiconductor chip, making them ideal candidates for point-of-care testing. In this article, we discuss the applications by specifically looking into point-of-care testing (POCT) using integrated optical sensors. The requirement and future perspective of integrated optical biosensors for POC is addressed.
Traditional methods
of monitoring biochemical reactions measure
certain detectable reagents or products while assuming that the undetectable
species follow the stoichiometry of the reactions. Here, based upon
the metal-oxide thin-film transistor (TFT) biosensor, we develop a
real-time molecular diffusion model to benchmark the concentration
of the reagents and products. Using the nicotinamide adenine dinucleotide
(NADH)–oxaloacetic acid with the enzyme of malate dehydrogenase
as an example, mixtures of different reagent concentrations were characterized
to extract the ratio of remaining concentrations between NAD
+
and NADH. We can thus obtain the apparent equilibrium constant of
the reaction, (8.06 ± 0.61) × 10
4
. Because the
whole analysis was conducted using a TFT sensor fabricated using a
semiconductor process, our approach has the advantages of exploring
biochemical reaction kinetics in a massively parallel manner.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.