title: Sulfadiazine-potentiometric sensors for flow and batch determinations of sulfadiazine in drugs and biological fluids.
abstract: New PVC membrane electrodes for the determination of sulfadiazine (SDZ) are presented. The electrodes are fabricated with conventional and tubular configurations with a graphite-based electrical contact, and no internal reference solution. The selective membranes consist of bis(triphenylphosphoranilidene)ammonium.SDZ (electrode A), tetraoctylammonium bromide (electrode B), or iron(II)-phthalocyanine (FePC) (electrode C) electroactive materials dispersed in a PVC matrix of o-nitrophenyl octyl ether (o-NPOE) plasticizer. The sensors A, B, and C displayed linear responses over the concentration ranges 1.0 x 10(-2) - 1.0 x 10(-5), 1.0 x 10(-2) - 7.5 x 10(-6), and 3.2 x 10(-2) - 7.0 x 10(-6) mol l(-1) (detection limits of 1.09, 2.04 and 0.87 microg ml(-1)) with anionic slopes of -57.3 +/- 0.1, -46.7 +/- 0.5, and -65.1 +/- 0.2 mV decade(-1), respectively. No effect from pH was observed within 4.0 - 5.5, 4.8 - 10, and 4.5 - 8, respectively, and good selectivity was found. The sensors were applied to the analysis of pharmaceuticals and biological fluids in steady state and in flow conditions.
authors.affiliation: REQUIMTE, Instituto Superior de Engenharia do Porto, R. Dr. António Bernardino de Almeida 431,4200-072 Porto, Portugal.
authors.forename: Ayman H
authors.initials: AH
authors.lastname: Kamel
authors.forename: Sofia A A
authors.initials: SA
authors.lastname: Almeida
authors.forename: M Goreti F
authors.initials: MG
authors.lastname: Sales
authors.forename: Felismina T C
authors.initials: FT
authors.lastname: Moreira
mesh_terms: D001826:Body Fluids / Q000737:chemistry*; D002675:Child, Preschool; D004566:Electrodes; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007223:Infant; D008567:Membranes, Artificial; D015394:Molecular Structure; D004364:Pharmaceutical Preparations / Q000737:chemistry*; D011143:Polyvinyl Chloride / Q000737:chemistry; D011199:Potentiometry; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013411:Sulfadiazine / Q000032:analysis*; D013997:Time Factors
chemical_list: D008567:Membranes, Artificial; D004364:Pharmaceutical Preparations; D013411:Sulfadiazine; D011143:Polyvinyl Chloride