Determination of roxithromycin from human plasma samples based on magnetic surface molecularly imprinted polymers followed by liquid chromatography-tandem mass spectromer.

• The matrix effect of the proposed method is significantly decreased by using MMIPs as sorbent.
• MMIP can provide a rapid and easy way for separation due to its magnetism.
• Extraction and enrichment were completed in a single step.

In this paper, a simple and reproducible method for the determination of roxithromycin in human plasma samples is proposed. The surface magnetic molecularly imprinted polymers (MMIPs) were utilized as sorbent. Roxithromycin was used as imprinted compound. The experimental results showed that the MMIPs had high affinity and selectivity toward roxithromycin. The extraction process was carried out in a single step by mixing the extraction solvent, MMIPs and human plasma samples by vortex. When the extraction process was completed, the MMIPs adsorbed the analyte were separated from the sample matrix by an external magnet due to the magnetism. The analyte eluted from the MMIPs was analysed by liquid chromatography-tandem mass spectrometry. Some main factors affecting the extraction of roxithromycin such as the amount of MMIPs, extraction solvent, extraction time, washing and elution conditions were optimized in this study. The calibration curve obtained by analyzing matrix-matched standards showed excellent linear relationship (r2 = 0.9997) in the concentration range of 10–1000 ng mL−1. The limit of detection and quantification obtained were 3.8 and 9.8 ng mL−1, respectively. The relative standard deviations of intra- and inter-day obtained were in the range of 3.9 %–5.5 % and 2.9 %–4.6 % with the recoveries ranging from 86.5 % to 91.5 %.