title: On-line hyphenation of solid-phase extraction to chromatographic separation of sulfonamides with fused-core columns in sequential injection chromatography.
abstract: On-line sample pretreatment (clean-up and analyte preconcentration) is for the first time coupled to sequential injection chromatography. The approach combines anion-exchange solid-phase extraction and the highly effective pentafluorophenylpropyl (F5) fused-core particle column for separation of eight sulfonamide antibiotics with similar structures (sulfathiazole, sulfanilamide, sulfacetamide, sulfadiazine, sulfamerazine, sulfadimidine, sulfamethoxazole and sulfadimethoxine). The stationary phase was selected after a critical comparison of the performance achieved by three fused-core reversed phase columns (Ascentis(®) Express RP-Amide, Phenyl-Hexyl, and F5) and two monolithic columns (Chromolith(®) High Resolution RP-18 and CN). Acetonitrile and acetate buffer pH 5.0 at 0.60 mL min(-1) were used as mobile phase to perform the separations before spectrophotometric detection. The first mobile phase was successfully used as eluent from SPE column ensuring transfer of a narrow zone to the chromatographic column. Enrichment factors up to 39.2 were achieved with a 500 µL sample volume. The developed procedure showed analysis time <10.5 min, resolutions >1.83 with peak symmetry ≤1.52, LODs between 4.9 and 27 µg L(-1), linear response ranges from 30.0 to 1000.0 µg L(-1) (r(2)>0.996) and RSDs of peak heights <2.9% (n=6) at a 100 µg L(-1) level and enabled the screening control of freshwater samples contaminated at the 100 µg L(-1) level. The proposed approach expanded the analytical potentiality of SIC and avoided the time-consuming batch sample pretreatment step, thus minimizing risks of sample contamination and analyte losses.
authors.affiliation: Centro de Energia Nuclear na Agricultura, Universidade de São Paulo, P.O. Box 96, 13400-970 Piracicaba SP, Brazil.
authors.forename: Alex D
authors.initials: AD
authors.lastname: Batista
authors.affiliation: Department of Analytical Chemistry, Faculty of Pharmacy, Charles University in Prague, Heyrovského 1203, Hradec Králové, Czech Republic. Electronic address: petr.chocholous@faf.cuni.cz.
authors.forename: Petr
authors.initials: P
authors.lastname: Chocholouš
authors.affiliation: Department of Analytical Chemistry, Faculty of Pharmacy, Charles University in Prague, Heyrovského 1203, Hradec Králové, Czech Republic.
authors.forename: Dalibor
authors.initials: D
authors.lastname: Satínský
authors.affiliation: Department of Analytical Chemistry, Faculty of Pharmacy, Charles University in Prague, Heyrovského 1203, Hradec Králové, Czech Republic.
authors.forename: Petr
authors.initials: P
authors.lastname: Solich
authors.affiliation: Centro de Energia Nuclear na Agricultura, Universidade de São Paulo, P.O. Box 96, 13400-970 Piracicaba SP, Brazil.
authors.forename: Fábio R P
authors.initials: FR
authors.lastname: Rocha
mesh_terms: D000900:Anti-Bacterial Agents / Q000032:analysis / Q000302:isolation & purification*; D002851:Chromatography, High Pressure Liquid / Q000295:instrumentation; D004867:Equipment Design; D017022:Flow Injection Analysis / Q000295:instrumentation; D057230:Limit of Detection; D045483:Rivers / Q000737:chemistry; D052616:Solid Phase Extraction / Q000295:instrumentation*; D013449:Sulfonamides / Q000032:analysis / Q000302:isolation & purification*; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000302:isolation & purification*
chemical_list: D000900:Anti-Bacterial Agents; D013449:Sulfonamides; D014874:Water Pollutants, Chemical
keywords: Anion-exchange; F5; Fused core; On-line SPE; Pentafluorophenylpropyl; SPE-SIC; Sequential Injection Chromatography; Sulfonamides