A MOF with high specific surface area for rapid separation and determination of β-adrenergic receptor blockers in pork by open-tubular capillary electrochromatography

Abstract

In this work, a novel Ti-based MOF (NH₂-MIL-125) bonded open-tubular (OT) column was firstly prepared via a one-step bonded growth method for capillary electrochromatography (CEC). The stationary phase was characterized by Fourier transform-infrared spectroscopy, scanning electron microscopy, X-ray diffraction spectroscopy, nitrogen adsorption–desorption isotherm measurements and zeta potential measurements. The results showed that the stationary phase exhibited a large specific surface area (1247.57 m² g⁻¹) with microporous and mesoporous structure and no obvious changes in the morphology/size inside and outside the column. Baseline separation of three β-adrenergic receptor blockers (Prop, Sot, and Lab), three β-adrenergic receptor agonists, and four sulfonamide antibiotics was obtained under the optimized CEC conditions with the shortest analysis time of 2.52 min and a maximum resolution of 11.52. The separation mechanisms were mainly attributed to the polarity and electrophoretic mobility of the analytes, as well as π–π interactions and hydrogen bonding interaction between the stationary phase and the analytes. A quantitative detection method for the three β-adrenergic receptor blockers in pork samples was established using the NH₂-MIL-125 bonded OT column. Good linearity (R² > 0.999) was obtained over the concentration range of 0.01–1.00 mg mL⁻¹ with limits of detection of 0.0044–0.0084 mg mL⁻¹ and recoveries of 90.24–106.74%. Thus, the developed method was simple, rapid and highly efficient, and could be applied for the simultaneous separation and detection of the three β-adrenergic receptor blockers in real samples.