Monitoring gestational diabetes at the point-of-care via dual glycated albumin lateral flow assays in conjunction with a handheld reader

Chronic conditions like diabetes require monitoring of vital biomarkers over extended periods of time. Monitoring gestational diabetes mellitus (GDM) is crucial to avoid short- and long-term adverse effects on both mother and infant. Providing monitoring systems to patients at the point-of-care (POC) has the potential to help mitigate these effects. In this manuscript, we propose the use of a sensing system combining lateral flow assays (LFAs) with a handheld colorimetric reader for use in tracking the glycemic status of a GDM patient at the POC. Current strategies of GDM monitoring include glucose and HbA1c measurements. These are often too frequent or not frequent enough for effective monitoring. Hence, we have developed a sensor for an intermediate interval biomarker - glycated albumin (GA). Based on the half-life of the protein, GA is measured once every 2-3 weeks. Here we first present two lateral flow assays, one for GA and another for total serum albumin used in conjunction with a handheld reader to read the colorimetric signals. Both assays have a sandwich aptamer format and measure the target proteins in their physiologically relevant ranges. The GA assay has a dynamic range of 3-20 mg ml and the serum albumin assay has a range of 20-50 mg ml without any sample dilution. Both LFAs were then incorporated into a single dual assay cartridge such that both assays could run simultaneously and provide the % glycated albumin value from a single test. Thus, the dual assay cartridge plus reader system has the potential to provide an effective platform for measuring GA for tracking GDM at the POC.