分子印迹固相萃取-高效液相色谱法测定水样中罗红霉素残留

Determination of roxithromycin residue in environmental water samples using molecularly imprinted solid phase extraction coupled with high performance liquid chromatography

采用沉淀聚合法,以罗红霉素(roxithromycin,Rox)为模板,甲基丙烯酸(methacrulic acid,MAA)为功能单体,乙二醇二甲基丙烯酸酯(ethylene glycol dimethacrylate,EGDMA)为交联剂,乙腈为致孔剂制备了Rox分子印迹聚合物(molecularly imprinted polymers,MIPs)。通过扫描电镜、平衡吸附实验等对制备的印迹聚合物进行表征和测定,结果表明MIPs对Rox具有特异性吸附作用,其最大表观结合量为19.03 mg/g。以制备的Rox-MIPs为吸附填料的分子印迹固相萃取柱,结合高效液相色谱法能快速检测环境水样中Rox的残留,线性范围为10~50 mg/L(r^2=0.9981),检出限(S/N=3)为0.28 mg/L。环境水样中不同添加水平下Rox的加标回收率为79.0%~91.8%,相对标准偏差(RSD)小于5%,该方法可用于环境样品中Rox残留的检测。

Molecularly imprinted polymers（ MIPs） for roxithromycin（ Rox） were prepared by precipitation polymerization,using Rox as template molecule,methacrulic acid（ MAA） as functional monomer,ethylene glycol dimethacrylate（ EGDMA） as cross-linker and acetonitrile as porogens. The characterizations of the prepared MIPs and non-imprinted polymers（ NIPs） were evaluated by scanning electron microscope（ SEM） and equilibrium adsorption experiments. The results showed that the MIPs possessed the specific adsorptivity toward Rox,and the apparent maximum binding capacity（ Qmax） was19. 03 mg/g. Using the prepared Rox-MIPs as selective adsorbent,the proposed molecularly imprinted solid phase extraction（ MISPE） coupled with high performance liquid chromatography（ HPLC） was successfully applied to determine Rox residue in water samples. A linear correlation was obtained over a range of 10-50 mg/L（ r^2= 0. 9981） with the limit of detection was 0. 28 mg/L（ S/N = 3）. The spiked recoveries of Rox were 79. 0%-91. 8 % with the relative standard deviations（ RSDs） of less than 5%. The proposed method is selective,sensitive and reliable for the analysis of Rox residue in water samples.