A portable and ecological paper-based device for glucose monitoring in peripheral blood mononuclear cell lysates

The increasing need for point-of-care (POC) testing has prompted a rise in the popularity of affordable biosensors that are eco-friendly, especially paper-based electrochemical sensors. This research introduces a biodegradable paper-based enzymatic biosensor for detecting glucose levels in intricate biological samples, such as cell lysates. This biosensor uses Prussian Blue (PB) as a mediator and glucose oxidase to detect glucose with excellent accuracy using direct electrochemical signals. Screen printing using Whatman filter paper produced a better biosensor than other substrates. The PB concentration of 12.5 mmol L^-1 was found to be optimal and resulted in an operating potential of -0.1 V, which helped decrease interference from other active substances and improved its selectivity. Calibration was found to be linear up to a concentration of 2 mmol L^-1 with a detection limit of 40 μmol L^-1 and a limit of quantification of 120 μmol L^-1. Moreover, experiments performed on cell lysates obtained from peripheral blood mononuclear cells (PBMCs) suggest the possible application of biosensors to measure glucose levels in vitro in both stimulated and unstimulated cells. This feature underscores its promise for use in monitoring metabolism and conducting diagnostic applications. The paper-based biosensor is an alternative to the current platform for the development of an eco-friendly, portable glucose-sensitive biosensor for point-of-care monitoring of glucose. Its flexibility and efficiency make it a strong candidate for use in the field of POC diagnostics, especially in areas of limited resources and in conditions where there is a problem with glucose dysregulation including diabetes and other related metabolic disorders.