Development of an analytical method for eight fluoroquinolones using solid-phase extraction and liquid chromatography with fluorescence detection

In this study, a practicable and effective analytical method based on solid-phase-extraction and reversed-phase liquid chromatography with fluorescence detection (SPE-LC-FLD) was developed and partially validated for routine analysis of eight FQs in wastewater at the trace level. Different SPE materials, pH conditions and eluents were modified to find an economic and effective SPE conditions. In our work, it is the first time that well-known commercially available SPE sorbent are compared to ‘generic’ cheap SPE sorbent. Aqueous samples (pH 2–3) were extracted using Anpel™ MEP cartridges where they were subsequently eluted by 6 mL of 2% formic acid in MeOH. The aqueous extracts were analysed by gradient elution LC-FLD, whose initial mobile phase was composed of ACN and 10 mmol L−1 tetrabutyl ammonium bromide (4/96, v/v, pH 3). The LODs and LOQs of the wastewater were as low as 0.32–2.12 ng L−1 and 1.07–7.07 ng L−1, respectively. The precisions of the overall method (RSD, n = 3) using wastewater were below ...