Simultaneous and confirmative detection of multi-residues of β₂-agonists and β-blockers in urine using LC-MS/MS/MS coupled with β-receptor molecular imprinted polymer SPE clean-up

Abstract

A liquid chromatography–linear ion-trap spectrometry (LC-MS³) method using β-receptor molecular-imprinted polymer (MIP) solid-phase extraction (SPE) as clean-up was developed to determine simultaneously and confirmatively residues of 25 β₂-agonists and 21 β-blockers in urine samples. Urine samples were subjected to enzymatic hydrolysis by β-glucoronidase/arylsulphatase, and then extracted with perchloric acid. Sample clean-up was performed using β-receptor MIP SPE. A Supelco Ascentis^® express Rp-Amide column was used to separate the analytes, and MS³ detection used an electrospray ionisation source in positive-ion mode. Recovery studies were carried out using blank urine samples fortified with the 46 analytes at the levels of 0.5, 1.0 and 2.0 μg l^–1. Recoveries were obtained ranging from 60.1% to 109.9% with relative standard deviations (RSDs, n = 7) from 0.5% to 19.4%. The limits of detection (LODs) and limits of quantitation (LOQs) of the 46 analytes in urine were 0.02–0.18 and 0.05–0.60 μg l^–1, respectively. As a result of the selective clean-up by MIP SPE and MS³ detection of the target drugs, the sensitivity and accuracy of the present method was high enough for monitoring β₂-agonist and β-blocker residues in urine samples. Satisfactory results were obtained in the process of the determination of positive urine samples.

Keywords:

• β₂-agonists
• β-blockers
• MIP SPE
• LC-MS
• urine

Acknowledgements

The authors would like to thank Michael Ye of Supelco, Division of Sigma-Aldrich, for his help in the preparation of this manuscript.

Funding

This study was supported by the National Natural Science Founding of China [grant number 20837003]; and by the Science and Technology Projects of the Ministry of Health [grant number 200902009].