Wang Ting, Tong Jia, Sun Mingli, Chen Ligang
Department of Chemistry, College of Science, Northeast Forestry University, Harbin, P. R. China.
J Sep Sci. 2011 Aug;34(15):1886-92. doi: 10.1002/jssc.201100046. Epub 2011 Jun 14.
The molecularly imprinted polymer (MIP) was synthesized and used as dispersant of matrix solid-phase dispersion (MSPD) for the extraction of chloramphenicol (CAP) in soil samples. The satisfactory recovery of CAP was obtained by the optimized extraction conditions: 1:2 as the ratio of sample to MIPs; 5 min as the dispersion time; 30% aqueous methanol as washing solvent and methanol as elution solvent. The CAP extracted from soil was determined by LC-MS/MS. The slight ion suppression phenomenon was observed for the CAP when the sample was cleaned up by MSPD with MIP as dispersant, when compared with C18 as MSPD dispersant, which caused significant ion suppression. LOD of CAP is 4.1 ng/g. RSDs of intra- and inter-day tests ranging from 3.1 to 6.2% and from 3.9 to 8.3% are obtained. At all three fortified levels (20, 100 and 500 ng/g), recoveries of CAP are in the range of 86.9-92.6%. The effect of ageing time of spiked soil sample on the CAP recovery was examined. The CAP recovery decreased from 91.0 to 36.9% when the ageing time changed from 1 day to 4 wk.
合成了分子印迹聚合物(MIP),并将其用作基质固相分散(MSPD)的分散剂,用于土壤样品中氯霉素(CAP)的萃取。通过优化萃取条件获得了满意的CAP回收率:样品与MIPs的比例为1:2;分散时间为5分钟;30%的甲醇水溶液作为洗涤溶剂,甲醇作为洗脱溶剂。采用液相色谱-串联质谱法(LC-MS/MS)测定从土壤中萃取的CAP。与以C18作为MSPD分散剂相比,当以MIP作为分散剂通过MSPD净化样品时,观察到CAP存在轻微的离子抑制现象,而以C18作为MSPD分散剂时会导致显著的离子抑制。CAP的检出限为4.1 ng/g。日内和日间测试的相对标准偏差分别为3.1%至6.2%和3.9%至8.3%。在所有三个加标水平(20、100和500 ng/g)下,CAP的回收率在86.9%至92.6%之间。考察了加标土壤样品的老化时间对CAP回收率的影响。当老化时间从1天变为4周时,CAP回收率从91.0%降至36.9%。