title: Electrochemical detection of glucose from whole blood using paper-based microfluidic devices.
abstract: Electrochemical paper-based analytical devices (ePADs) with integrated plasma isolation for determination of glucose from whole blood samples have been developed. A dumbbell shaped ePAD containing two blood separation zones (VF2 membranes) with a middle detection zone was fabricated using the wax dipping method. The dumbbell shaped device was designed to separate plasma while generating homogeneous flow to the middle detection zone of the ePAD. The proposed ePADs work with whole blood samples with 24-60% hematocrit without dilution, and the plasma was completely separated within 4 min. Glucose in isolated plasma separated was detected using glucose oxidase immobilized on the middle of the paper device. The hydrogen peroxide generated from the reaction between glucose and the enzyme pass through to a Prussian blue modified screen printed electrode (PB-SPEs). The currents measured using chronoamperometry at the optimal detection potential for H2O2 (-0.1 V versus Ag/AgCl reference electrode) were proportional to glucose concentrations in the whole blood. The linear range for glucose assay was in the range 0-33.1 mM (r(2)=0.987). The coefficients of variation (CVs) of currents were 6.5%, 9.0% and 8.0% when assay whole blood sample containing glucose concentration at 3.4, 6.3, and 15.6mM, respectively. Because each sample displayed intra-individual variation of electrochemical signal, glucose assay in whole blood samples were measured using the standard addition method. Results demonstrate that the ePAD glucose assay was not significantly different from the spectrophotometric method (p=0.376, paired sample t-test, n=10).
authors.affiliation: Graduate Program in Clinical Biochemistry and Molecular Medicine, Faculty of Allied Health Sciences, Chulalongkorn University, Patumwan, Bangkok, Thailand.
authors.forename: Julaluk
authors.initials: J
authors.lastname: Noiphung
authors.forename: Temsiri
authors.initials: T
authors.lastname: Songjaroen
authors.forename: Wijitar
authors.initials: W
authors.lastname: Dungchai
authors.forename: Charles S
authors.initials: CS
authors.lastname: Henry
authors.forename: Orawon
authors.initials: O
authors.lastname: Chailapakul
authors.forename: Wanida
authors.initials: W
authors.lastname: Laiwattanapaisal
mesh_terms: D001786:Blood Glucose / Q000032:analysis* / Q000302:isolation & purification; D002138:Calibration; D055664:Electrochemical Techniques / Q000295:instrumentation* / Q000379:methods*; D004566:Electrodes; D004800:Enzymes, Immobilized / Q000737:chemistry; D004867:Equipment Design; D005949:Glucose Oxidase / Q000737:chemistry; D006400:Hematocrit; D006801:Humans; D006861:Hydrogen Peroxide / Q000737:chemistry; D008567:Membranes, Artificial; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation*; D010209:Paper; D015203:Reproducibility of Results
chemical_list: D001786:Blood Glucose; D004800:Enzymes, Immobilized; D008567:Membranes, Artificial; D006861:Hydrogen Peroxide; D005949:Glucose Oxidase
keywords: Electrochemical detection; Glucose; Lab-on-paper; Paper-based microfluidic devices; Wax dipping; Whole blood