title: Portable system for the detection of micromolar concentrations of glucose.
abstract: Glucose in non-invasively collected biofluids is generally in the micromolar range and thus, requires sensing methodologies capable of measuring glucose at these levels. Here, we present a small fluorometer system that can quantify glucose in the range of 0-5 μM with resolution of ~0.07 μM. It relies on the glucose binding protein (GBP) fluorescently labeled with two fluorophores. Fluorescence signals from the dual-labeled GBP are utilized in a ratiometric mode, making the measurements insensitive to variations in protein concentration and other systematic errors. Fluorescence is quantified by a miniature, dedicated ratiometric fluorometer that is powered via USB. Concentration is calculated using an ultra-mobile personal computer (UMPC). The whole system is designed to be pocket sized suitable for point-of-care or bedside applications. Test results suggest that the system is a promising tool for accurate measurements of low glucose concentrations (0.1-10 μM) in biological samples.
authors.affiliation: Center for Advanced Sensor Technology, Department of Chemical, Biochemical and Environmental Engineering, University of Maryland Baltimore County, 1000 Hilltop Circle, Baltimore MD, 21250.
authors.forename: Yordan
authors.initials: Y
authors.lastname: Kostov
authors.affiliation: Center for Advanced Sensor Technology, Department of Chemical, Biochemical and Environmental Engineering, University of Maryland Baltimore County, 1000 Hilltop Circle, Baltimore MD, 21250.
authors.forename: Xudong
authors.initials: X
authors.lastname: Ge
authors.affiliation: Center for Advanced Sensor Technology, Department of Chemical, Biochemical and Environmental Engineering, University of Maryland Baltimore County, 1000 Hilltop Circle, Baltimore MD, 21250.
authors.forename: Govind
authors.initials: G
authors.lastname: Rao
authors.affiliation: Center for Advanced Sensor Technology, Department of Chemical, Biochemical and Environmental Engineering, University of Maryland Baltimore County, 1000 Hilltop Circle, Baltimore MD, 21250.
authors.forename: Leah
authors.initials: L
authors.lastname: Tolosa
keywords: Glucose sensor; florescence; portable system