title: Fully integrated whole blood testing by real-time absorption measurement on a centrifugal platform.
abstract: We present a novel microfluidic concept to enable a fast colorimetric alcohol assay from a single droplet of whole blood. The reduced turn-around time of 150 seconds is, on the one hand, achieved by a full process integration including metering, mixing with reagents, and sedimentation of cellular constituents. On the other hand, our novel total internal reflection (TIR) scheme allows to monitor the increase of the absorbance values in real-time. Thus, the saturation values can be predicted accurately based on an extrapolation of real-time measurements acquired during a 100 second initial period of rotation. Additionally, we present a metering structure to define nanolitre sample volumes at a coefficient of variation (CV) below 5%.
authors.affiliation: University of Freiburg-IMTEK, Department of Microsystems Engineering, Laboratory for MEMS Applications, Georges-Koehler-Allee 106, D-79110 Freiburg, Germany. steigert@imtek.de
authors.forename: J
authors.initials: J
authors.lastname: Steigert
authors.forename: M
authors.initials: M
authors.lastname: Grumann
authors.forename: T
authors.initials: T
authors.lastname: Brenner
authors.forename: L
authors.initials: L
authors.lastname: Riegger
authors.forename: J
authors.initials: J
authors.lastname: Harter
authors.forename: R
authors.initials: R
authors.lastname: Zengerle
authors.forename: J
authors.initials: J
authors.lastname: Ducrée
mesh_terms: D001774:Blood Chemical Analysis; D002151:Calorimetry; D000431:Ethanol / Q000097:blood*; D006801:Humans; D046210:Microfluidic Analytical Techniques; D044085:Microfluidics; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D000431:Ethanol