Microwave-assisted micro-solid-phase extraction for analysis of tetracycline antibiotics in environmental samples

In this study, a novel solid-liquid-solid extraction approach, which was termed 'microwave-assisted micro-solid-phase extraction' (MAE-mu-SPE), was developed. Target analytes were extracted from the sample into extraction solvent enhanced by microwave field, following adsorption by the adsorbent in the micro-solid-phase extraction device. Without any clean-up steps, the extracts were analysed by high performance liquid chromatography coupled with ultra-violet detector. The MAE-mu-SPE approach was developed for the extraction of four tetracycline antibiotics residues in environmental soil, sludge and atmospheric particulate matters. Variables affecting extraction procedures were systematically investigated. Low detection limits of 0.1-6.3ng/g and low quantification limits of 0.33-20.7ng/g were achieved under optimised conditions. The recoveries of antibiotics ranged from 70.6% to 110.5% with relative standard deviation of less than 15.1%. The predominance was showed when compared to conventional MAE and mu-SPE method. According to the results, MAE-mu-SPE was proved to be a simple and effective sample preparation method for the analysis of trace organic contaminants in environmental samples.