Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1245799 | Talanta | 2006 | 8 Pages |
Abstract
In this study, a sorbent flow preconcentration system coupled to amperometric detector for the chloroguaiacol (4-chloro-2-methoxyphenol) determination at submicromolar levels is described. The satisfactory selectivity of the proposed method was attained by means of the use of a chloroguaiacol-imprinted polymer, whose the synthesis was carried out by bulk polymerization. Flow and chemical parameters associated to the preconcentration system, such as sample pH, preconcentration and elution flow rates, concentration of the carrier solution (KCl) and eluent volume were investigated through multivariate analysis. The flow preconcentration of chloroguaiacol was not affect by equimolar presence of structurally similar phenolic compounds including catechol, 4-chloro-3-methylphenol, 4-aminophenol and 2-cresol, thus showing the good performance of the imprinted polymer. Under the best experimental conditions, it was obtained a preconcentration factor of 110-fold and low detection and quantification limits of 27 and 78 nmol Lâ1, respectively. The analytical curve covered a wide linear range from 0.05 up to 5.0 μmol Lâ1 (r > 0.999) and satisfactory precision (n = 8) evaluated by relative standard deviation (R.S.D.) were respectively, 5.5 and 4.2%, for solutions of 1.0 and 5.0 μmol Lâ1 chloroguaiacol. Other parameters related to the performance of the flow system were also evaluated including concentration efficiency of 27.5 minâ1 and consumptive index of 0.09 mL. Recoveries varying from 93 up to 112% for water samples (tap water and river water) spiked with chloroguaiacol concentration were achieved, thus assuring the accuracy of the proposed flow preconcentration system.
Related Topics
Physical Sciences and Engineering
Chemistry
Analytical Chemistry
Authors
César Ricardo Teixeira Tarley, Mariana Gava Segatelli, Lauro Tatsuo Kubota,