Dummy-template molecularly imprinted solid phase extraction for selective analysis of ractopamine in pork

• Published in: Food chemistry 2013-08, Vol.139 (1-4), p.24-30
• Main Authors: Du, Wei, Fu, Qiang, Zhao, Gang, Huang, Ping, Jiao, Yuanyuan, Wu, Hao, Luo, Zhimin, Chang, Chun
• Format: Article
• Language: English
• Subjects: adsorption; Animals; Biological and medical sciences; Chromatography, High Pressure Liquid; detection limit; Dummy-template; Food Contamination; Food industries; Fourier transform infrared spectroscopy; Fundamental and applied biological sciences. Psychology; Growth Substances - chemistry; Growth Substances - isolation & purification; In situ polymerisation; Liquid chromatography- mass spectrometry; mass spectrometry; Meat - analysis; Meat and meat product industries; mercury; Molecular Imprinting; Molecularly imprinting polymers; Phenethylamines - chemistry; Phenethylamines - isolation & purification; polymers; Polymers - chemical synthesis; Polymers - chemistry; pork; Ractopamine; scanning electron microscopy; Solid phase extraction; Solid Phase Extraction - instrumentation; Solid Phase Extraction - methods; Spectroscopy, Fourier Transform Infrared; Swine
• ISSN: 0308-8146; 1873-7072
• DOI: 10.1016/j.foodchem.2013.01.109

► Molecularly imprinted polymers (MIPs) for ractopamine were prepared as solid-phase extraction (SPE). ► Salbutamol was used as the dummy-template of the MIPs. ► The adsorption mechanism of MIPs followed Freundlich isotherm model and pseudo second order model. ► MISPE coupled with LC–MS method was developed for the determination of RAC in pork sample. Molecularly imprinted polymers (MIPs) for selective adsorption of ractopamine hydrochloride (RAC) were synthesised by an in situ method, in which salbutamol (SAL) was used as the dummy-template to avoid the template leakage. Scanning electron microscopy (SEM), mercury porosimerty and Fourier transform infrared spectroscopy (FTIR) were used to investigate the physical and morphological characteristics of the dummy-template MIPs. The test of adsorption selectivity indicated that the dummy-template MIPs exhibited high selectivity to RAC. The saturated adsorption capacity for RAC on dummy-template MIPs was 90.9μgg−1. Based on the dummy-template polymers, a liquid chromatography–mass spectrometry (LC–MS) method was developed for the selective analysis of RAC in real pork samples. The averages of intra- and inter-day accuracy ranged from 78.9% to 92.2% and from 90.7% to 93.1%, respectively. The RSD% of repeatability ranged from 1.9% to 6.3%, and the RSD% of intermediate precision ranged from 3.5% to 9.2%, while the limit of detection (LOD) was 0.02μgkg−1.