title: Kinetic methods for the determination of cadmium(II) based on a flow-through bulk optode.
abstract: Three kinetic methods based on flow injection, flow, and stopped-flow injection were applied for the determination of Cd(II) using a flow-through bulk optode membrane that incorporates 1-(2-pyridylazo)-2-naphtol (PAN) in a plasticized poly(vinyl) chloride membrane entrapped in a cellulose support. The calibration graphs plotting the reflectance at 560 nm versus [Cd(II)](1/2) for the first two methods and versus [Cd(II)] for the third were linear up to 56.2 mg l(-1). The detection limits of the methods were 0.01, 0.06 and 0.8 mg l(-1), respectively. The FI method was selected for application purposes. The variation coefficient of the sensor response for 11.2 mg l(-1) of Cd(II) was +/-0.31 and +/-0.65% between different membranes. The sensor can be readily regenerated with a carrier (acetic-acetate) buffer of pH 4. The FI method was applied to the determination of cadmium in an alloy and in water.
authors.affiliation: Department of Analytical Chemistry, Faculty of Chemistry, University of Murcia, 30071 Murcia, Spain.
authors.forename: C
authors.initials: C
authors.lastname: Sanchez-Pedreño
authors.forename: M S
authors.initials: MS
authors.lastname: García
authors.forename: J A
authors.initials: JA
authors.lastname: Ortuño
authors.forename: M I
authors.initials: MI
authors.lastname: Albero
authors.forename: R
authors.initials: R
authors.lastname: Expósito