title: Disposable luminol copolymer-based biosensor for uric acid in urine.
abstract: A new electrochemiluminescent (ECL) disposable biosensor for uric acid was manufactured by immobilization in a double-layer design of luminol as a copolymer with 3,3',5,5'-tetramethylbenzidine (TMB) and the enzyme uricase in chitosan on gold screen-printed cells. The good mechanical and improved electroluminescent characteristics of the new copolymer poly(luminol-TMB) make it possible to determine uric acid by measuring the growing ECL emission with the analyte concentration. The combination of enzymatic selectivity with ECL sensitivity results in a disposable analytical device with a linear range for uric acid from 1.5×10(-6) to 1.0×10(-4) M, a limit of detection of 4.4×10(-7) M and a precision of 13.1% (1.0×10(-5) M, n=10) as relative standard deviation. Satisfactory results were obtained for uric acid determination in 24h-urine samples compared to a reference procedure. This uric acid biosensor can be used as a low-cost alternative to conventional methods.
authors.affiliation: ECsens, Department of Analytical Chemistry, Campus Fuentenueva, Faculty of Sciences, University of Granada, E-18071 Granada, Spain.
authors.forename: J
authors.initials: J
authors.lastname: Ballesta-Claver
authors.forename: I F
authors.initials: IF
authors.lastname: Díaz Ortega
authors.forename: M C
authors.initials: MC
authors.lastname: Valencia-Mirón
authors.forename: L F
authors.initials: LF
authors.lastname: Capitán-Vallvey
mesh_terms: D001560:Benzidines / Q000737:chemistry*; D015374:Biosensing Techniques / Q000191:economics / Q000295:instrumentation / Q000379:methods*; D048271:Chitosan / Q000737:chemistry; D004209:Disposable Equipment; D004566:Electrodes; D006046:Gold / Q000737:chemistry; D006801:Humans; D008163:Luminescent Measurements / Q000379:methods*; D008165:Luminol / Q000737:chemistry*; D012680:Sensitivity and Specificity; D013997:Time Factors; D014503:Urate Oxidase / Q000737:chemistry / Q000378:metabolism; D014527:Uric Acid / Q000652:urine*
chemical_list: D001560:Benzidines; D014527:Uric Acid; C021758:3,3',5,5'-tetramethylbenzidine; D008165:Luminol; D006046:Gold; D048271:Chitosan; D014503:Urate Oxidase