Automatic solid-phase extraction by programmable flow injection coupled to chromatographic fluorimetric determination of fluoroquinolones

Abstract

Automatic sample preparation targeting preconcentration of fluoroquinolones present in environmental waters.

Screening of fluoroquinolones in environmental waters using disk-based solid-phase extraction combined to microplate fluorimetric determination and LC-MS/MS

“…The time taken in sample loading and post-elution operations are minimized by automated [25] or online SPE [14] schemes, but both strategies require dedicated equipment and trained technicians. Concerning the amount of solvent required for elution of FQs retained in the solid sorbent, the approach presented in this work is clearly more environmentally friendly when compared to previous work, requiring only 1 mL of eluent, while 2.5 to 10 mL of eluent are required (Table S4) in most of the conventional SPE strategies proposed before.…”

“…Recently, different methods have been applied for determination of FQs [12], such as capillary electrophoresis [13], high pressure liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) [14][15][16][17][18][19], coupled to diode array detection [20,21], or coupled to resonance light scattering [22]. Fluorimetric-based methods have also been developed based on FQs intrinsic fluorescent properties as in the proposed methodology for quantification of CIP in seawater at ng L −1 level [23], or in the screening method applied in groundwater samples from intensive livestock production systems [24], or even resorting to automation for preconcentration in molecularly imprinted polymers [25]. Fluorescent labelling of FQs followed by chromatographic-fluorimetric detection has also been recently applied for the determination of CIP and NOR in surface water [26].…”

“…In this context, solid-phase extraction (SPE) has been implemented for sample preparation as it copes with rather large sample volumes (50-100 mL). Sorbents such as polymer-based Strata-X [15], molecularly imprinted polymers [23,25] and also restricted-access material based on bovine serum albumin and C8 [14] have been used for preconcentration of FQs from water samples, mainly in cartridge format.…”

Flow-Injection Methods in Water Analysis—Recent Developments

“…It should be mentioned that the most common manual titrimetric methods with different detections are employed for millimolar rather than sub-mg L −1 concentrations of the analytes (except for some special techniques of microtitration). Very few reported determinations of organic analytes are carried out, mostly in FIA or SIA systems hyphenated to high-performance chromatographic separations [74,79,80,91]. Abbreviations used: CFA-continuous flow analysis system, COD-chemical oxygen demand, ET-AASelectrothermal atomic absorption spectrometry, FIA-flow injection analysis system, IC-ion-chromatography, LOV-lab-on-valve, SIA-sequential injection analysis system, SIC-sequential injection chromatography, SPEsolid-phase extraction, TDN-total dissolved nitrogen, TDP-total dissolved phosphorus, TLS-thermal lens spectrometry, UV/Vis abs.-UV/Vis absorption spectrophotometry.…”