Solvent-free microwave-assisted extraction of fluoroquinolones from soil and liquid chromatography-fluorescence determination.
Presented hereafter is a novel method entailing solvent free microwave-assisted extraction (MAE) and HPLC equipped with Fluorimetric Detector (HPLC-FD) for the simultaneous determination at μgkg(-1) concentration of eight fluoroquinolone antibiotics (FQs) (Ciprofloxacin, Danofloxacin, Enrofloxacin, Flerofloxacin, Levofloxacin, Marbofloxacin, Norfloxacin and Orbifloxacin) in agricultural soils. The extraction was quantitatively performed, in a single step, by using an aqueous solution containing Mg(II) as complexing agent, thus avoiding consumption of organic solvents. The optimal MAE conditions have been established through a chemometric approach by considering temperature, irradiation time and matrix moisture or solvent, as the most important recognized variables affecting the extraction yield. Satisfying recoveries (69-110%, spikes 0.03-0.5mgkg(-1)) were gained with a single MAE cycle of 20min, at 80°C in 20% (w/v) Mg(NO(3))(2) solution as leaching agent. MAE-SPE recoveries at 10μgkg(-1), concentration near method quantification limits (MQLs), were in the range 60-85%. Good repeatability and within-lab reproducibility were observed (both in the range 1-16%). The applicability of the method to real samples was assessed on natural contaminated soils. Compared to ultrasonic-assisted extraction (UAE), MAE was shown to be highly competitive in terms of extraction efficacy and analysis speed.
Sturini
Michela
M
Department of General Chemistry, University of Pavia, via Taramelli 12, 27100 Pavia, Italy.
Speltini
Andrea
A
Maraschi
Federica
F
Rivagli
Elisa
E
Profumo
Antonella
A
D000900:Anti-Bacterial Agents / Q000032:analysis / Q000302:isolation & purification*; D002851:Chromatography, High Pressure Liquid / Q000295:instrumentation / Q000379:methods*; D005453:Fluorescence; D024841:Fluoroquinolones / Q000032:analysis / Q000302:isolation & purification*; D008872:Microwaves; D012989:Soil Pollutants / Q000032:analysis / Q000302:isolation & purification*; D052616:Solid Phase Extraction / Q000295:instrumentation / Q000379:methods*
D000900:Anti-Bacterial Agents; D024841:Fluoroquinolones; D012989:Soil Pollutants