Determination of quinolone antibiotics by biomass waste-monolithic spin columns-solid phase extraction coupled with liquid chromatography

A simple, green and rapid method for the simultaneous determination of three kinds of quinolone antibiotics (QNs) from environmental water samples and biological samples was established by monolithic spin columns-solid phase extraction coupled with high performance liquid chromatography (MSC-SPE-HPLC). The QNs was completely adsorbed by 300 mg spent coffee grounds as the sorbents of MSC-SPE at 1000 rpm, and eluted by 2500 μL acetonitrile and 4% acetic acid (60:40, V:V). The efficient and rapid elution was obtained under the speed of 500 rpm. After separation on a Pursuit 5 C18 column (250 mm×4.6 μm, 5 μm), the samples were determined. The three QNs showed good liner relationship in the range of 0.1-10 μg/mL with the correlation coefficients greater than 0.998. The limit of detection (LODs, S/N=3) for ciprofloxacin, norfloxacin and enrofloxacin was 33.3 ng/mL.Moreover, the recoveries were 70.3-112.6% at three spiked levels (0.5, 1 and 2 μg/mL) with the relative standard deviation 1.02-9.78%. The obtained results revealed that the method was simple to operate, green and environment-friendly, and could be used for the determination of antibiotics in environmental samples.