Extraction And Detection Method Of Trace Residue Of Olaquindox Based On MIP

Background Olaquindox, also known as bayonox, is widely used in feed and feed additives since it has wide antimicrobial spectrum, could increase growth rate, and promote the cattle and poultry to digest and utilize the feed. Because of its cumulative toxicity, olaquindox will cause poisoning and even death of animals. Organic solvent treatment which is difficult to meet the requirements of trace detection since the pre-process methods always are complexity, time consuming, bad selectivity, low extraction yield and purifying rate, and the environmental pollution induced by organic solvent. Since the matrix solid-phase dispersion simplifies the Pre-processor, selective extraction would be achieved with the molecularly imprinted polymer as the stuffing in matrix solid-phase dispersion. Currently, the detection methods of olaquindox residue mainly were ultra violet spectrophotometry, thin layer chromatography, high performance liquid chromatography and capillary electrophoresis and so on. Such methods were all need complicated pre-process to treat the sample and a large number of reagent consumption. In addition, it is difficult to achieve complete baseline separation of olaquindox and its analogue using traditional methods. The separation problem will be solved according to the method that MSPDE-HPLC based on the molecular imprinting. The using of the monolithic column prepared with the method of in-situ polymerization will reduce the using of organic solvent and achieve nice separation of olaquindox and its analogue.Objective A rapid detection method of trace olaquindox residues in meat products was established. The molecularly imprinted polymer of olaquindox was elected as the adsorbent of matrix solid phase dispersion extraction to simultaneously extract and purify olaquindox in meat products, and then detected by HPLC. The synthesis of MIP is operated through bulk polymerization and thermal initiation under the optimized conditions. In addition, the monolithic column for capillary electrophoresis was prepared under the optimized reaction conditions.Method The synthesis of MIP is operated through bulk polymerization and thermal initiation under the optimized conditions. The MIP of olaquindox with nice absorption capability was chosen according to adsorption kinetics.The assessment processes involve solution selection, adsorption equilibrium experiments, selective experiments and adsorption time selection. The selected MIP was used as the specific adsorbent to olaquindox residue in meat products by matrix solid phase dispersion extraction. The eluent of MSPDE were prepared by methanol and glacial acetic acid at the ratio of 8:2 (v/v) and olaquindox was tested by HPLC. Then this new method was compared with the traditional matrix solid phase dispersion extraction method. Meanwhile, Monolithic column was prepared under the optimal synthesis conditions and the one that with high selectivity and permeability was chosen by optimize the preparation conditions. The monolithic column with good selectivity and permeability were prepared and the segregation analysis conditions were further optimized.Result The performance of polymer were evaluated by the comparison of the adsorption capacity between MIP and NMIP, the adsorption capacity of MIP to olaquindox is 41.64 mg·g-1 with the imprinting factor is 3.97 and the highest adsorption capacity of NMIP is 10.50 mg·g-1. The partition ratio, obtained through selective experiments, of MIP to olaquindox, quinocetone and mequindox are 559.32, 123.29 and 128.96, respectively. The relative selection coefficients of MIPs to them are 4.77, 1.94 and 2.27, respectively. The result shows that MIP has high selectivity and identification ability only to olaquindox. The coefficient of recovery and RSD are 89.72% and 1.59% in matrix solid-phase dispersion experiment with MIP as the extracting agent. This result was better than the 50.16% and 3.58% which were obtained with Alumina N-neutral as the extracting agent. The result shows that separative efficiency of MIP is higher than the traditional extracting agent. Finally, using the monolithic columns for CE method, olaquindox will appear within 20 minutes. Conclusion This research established the MSPDE-HPLC analysis method through optimizing the preparing conditions of MIP and monolithic column, matrix solid phase dispersion extraction and CE conditions. This research builds the MSPDE-HPLC analysis method of olaquindox in the food products and builds the online enrichment test method with the monolithic column of CE.