Detection of three kinds of β-Agonists in milk powder by molecularly imprinted solid phase extraction-high performance liquid chromatography

In this study, three single-template molecular imprinted polymers (SMIP) and three mixed templatemolecular imprinted polymers(MMIP) were prepared by precipitation polymerization using 3-methoxytyine(3-MT), dopamine (DA) and phenylephrine (PE) as the templates, and their adsorption and separation performance were evaluated in water and ethanol. The performance tests showed that the adsorption capacity of SMIP1 with 3- MT as template had the best selectivity for the above three ݭAgonists in ethanol, and the adsorption equilibrium can be reached at 25 min. When the initial concentration of 0.03 mmol/L, the imprinting factor (IF) reached the highest value of 2.12. The adsorption capacity of SMIP1 for 3-MT, DA and PE increased with the initial concentration, reaching 41.26, 39.83 and 40.47 µmol/g at 3 mmol/L, respectively. The selective simultaneous extraction of 3-MT, DA and PE from milk powder were achieved by employing this SMIP1 as a solid phase extraction adsorbent. At the spiked concentrations of 0.01, 0.02 and 0.03 mmol/L, the mean recoveries of 3-MT, DA and PE, as detected by high performance liquid chromatography (HPLC) method, ranged from 98% to 100%, 92.5% to 96%, and 90.3% to 94%, respectively. The relative standard deviations (RSDs) ranged from 1.9% to 5.1%, 2.0% to 4.0% and 2.1% to 4.2%, respectively. This method is suitable for quantitative analysis of 3- MT and qualitative detection of DA and PE in milk powder. © 2024, Youke Publishing Co.,Ltd. All rights reserved.