| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1243437 | Talanta | 2015 | 8 Pages |
•Hyphenated solid phase extraction with on-line chromatography.•Comparison of five columns for separation of eight sulfonamide antibiotics.•Comparison of three anion exchange resins for fresh water sample pretreatment.•Extending of capabilities of the Sequential Injection Chromatography system.•High performance and cost-saving method for environmental analysis.
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 (r2>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.
