title: Determination of L- and D-fucose using amperometric electrodes based on diamond paste.
abstract: Monocrystalline diamond (natural diamond, synthetic-1 and synthetic-2) based electrochemical electrodes were designed for the analysis of L- and D-fucose. Response characteristics of the electrochemical electrodes were determined using cyclic voltammetry and differential pulse voltammetry (DPV). L-fucose was determined using DPV with electrodes based on natural diamond, synthetic-1 and synthetic-2, respectively, at 240 mV using NaCl as the electrolyte (pH 3.0); at 160 mV using KNO(3) (pH 10.0) and at 80 mV using KCl as the electrolyte (pH 10.0) while D-fucose was analyzed at 120 mV using KCl as the electrolyte (pH 1.0); at 140 mV using KNO(3) as the electrolyte (pH 1.0) and at 160 mV using NaNO(3) as the electrolyte (pH 3.0). The linear concentration ranges for L-fucose were between 10(-13) and 10(-9) mol L(-1) (natural diamond), 10(-11) and 10(-8) mol L(-1) (synthetic-1) and 10(-6) and 10(-3) mol L(-1) (synthetic-2) with detection limits of 10(-14), 10(-12) and 10(-8) mol L(-1) magnitude order, respectively. For D-fucose, the linear concentration ranges were 10(-6) to 10(-3) mol L(-1) (natural diamond), 10(-5) to 10(-3) mol L(-1) (synthetic-1) and 10(-9) to 10(-3) mol L(-1) (synthetic-2) with detection limits of 10(-7), 10(-7) and 10(-10) mol L(-1) magnitude order, respectively. The sensors were used for the assay of L-fucose in serum and urine samples.
authors.affiliation: Laboratory of Electrochemistry and PATLAB Bucharest, National Institute of Research for Electrochemistry and Condensed Matter, 202 Splaiul Independentei Str., 060021, Bucharest, Romania. iustinavanstaden@yahoo.com
authors.forename: Raluca-Ioana
authors.initials: RI
authors.lastname: Stefan-van Staden
authors.forename: R'afat Mahmoud
authors.initials: RM
authors.lastname: Nejem
authors.forename: Jacobus Frederick
authors.initials: JF
authors.lastname: van Staden
authors.forename: Hassan Y
authors.initials: HY
authors.lastname: Aboul-Enein
mesh_terms: D018130:Diamond / Q000737:chemistry; D055664:Electrochemical Techniques / Q000295:instrumentation* / Q000379:methods*; D004566:Electrodes; D005643:Fucose / Q000032:analysis*; D057230:Limit of Detection; D013237:Stereoisomerism
chemical_list: D005643:Fucose; D018130:Diamond