Analysis of macrolide antibiotics in water by magnetic solid-phase extraction and liquid chromatography-tandem mass spectrometry.

Macrolides are one of the most commonly used families of antibiotics employed in human and veterinary treatment. These compounds are considered emerging contaminants with potential ecological and human health risks that could be present in surface water. This paper describes the development and application of a simple and efficient extraction procedure for the determination of tilmicosin; erythromycin, tylosin and erythromycin-HO from water samples. Sample extraction was carried out using magnetic solid-phase extraction using oleate functionalized magnetic nanoparticles followed by LC-MS/MS analysis. The effects of several parameters on the extraction efficiency of MLs from water were evaluated. The recovery results obtained were >84% for most of the compounds, except for erytromycin. The LOD and LOQ values ranged from 11.5 to 26ngL and from 34 to 77ngL, respectively. The selected method was applied to monitor these contaminants in water samples from different sources. Tilmicosin and tylosin were not detected in any of the samples, but erythromycin and erythromycin-HO were found in 50% of the surface water samples at levels from <LOQ to 264ngL and 149ngL, respectively.