Detection Of Enrofloxacin In Chicken Muscle By MISPE-HPCE

With the development of society, the rate of animal-derived food in the diet of people is growing. However, hazards of the drug residues, additives and others on human body is also growing. China as an important exporter for domestic animal products,will be faced the technical barriers on drug residues for a long time. So, it will be the focus of residue analysis that many types and multi-component residues in the sample pre-treatment and efficient detection technology.With high selectivity, good stability and simple preparation, molecularly imprinted polymer can be used to isolate and enrich the residue from the complex matrix in the pre-treatment of sample.In this paper, the enrofloxacin molecularly imprinted polymer was prepared by means of high performance capillary electrophoresis (HPCE ). The methods assaying eight kinds multi-component residues of veterinary drugs by high performance capillary electrophoresis and determining the enrofloxacin in chicken muscle by MISPE-HPCE were established.The main research contents are as follows:1. Preparation of enrofloxacin molecularly imprinted polymer Using enrofloxacin as template molecule,α-methacrylic acid as functional monomer. dichloromethane as solvent, EDMA as cross linker, AIBN as initiator, enrofloxacin's molecularly imprinted polymer was synthesized.The binding power and selectivity of molecularly imprinted polymer(MIP) were researched by HPCE. The results showed that the enrofloxacin's imprinted polymer have strong binding power to enrofloxacin. The largest binding constant is Qmax1=8.0385μmol·g-1, Qmax2=4.5357μmol·g-1. Enrofloxacin MIPs have high selectivity on the combination of enrofloxacin. It showed that the recoveries of MIPs and non-molecularly imprinted polymer(NMIP) binding rate to enrofloxacin,ofloxacin and pefloxacin respectively are for 78.4%,33.9%,37.3% and 30.8%,19.2%,21.5%。2. Establishment of the detection method of eight veterinary drug residue including enrofloxacin by high performance capillary electrophoresisThe detection separation method of eight veterinary drug residue was established by HPCE. To determine preliminary of the best condition, influences of the types of electrophoretic buffer, ion concentration, pH, voltage and temperature's to separation were investigated. According to the resolution of the two adjacent chromatographic peaks as index, the best separation condition was introduced by orthogonal experiment with pH,voltage and temperature as factors, and with three levels of each factors: Buffer solution is Na2HPO4(40 mmol/ L)- citric acid(20 mmol/ L), pH is 8.47, voltage is 22 kV, temperature is 20℃, detection wavelength is 262 nm. Result showed that eight drugs seperated completely in 9 min. And the concentration and the peak area of each component showed good linear relationship. r= 0.999～0.999 5, RSD is 0.44%～1.15%(migration time) and 1.12%～2.32%(peak area).The method is quickly,convenient and accurately.3. Establishment of the detection method of enrofloxacin MISPE-HPCE in Chicken muscle tissueThe method of enrofloxacin Molecularly imprinted solid phase extraction(MISPE) in in Chicken was established. MISPE columns of Enrofloxacin were filled with enrofloxacin MIPs (usually 50 ~ 500 mg). The effect of different eluent to enrofloxacin in chicken muscle tissue are contrasted. It showed that it is the best way to choose n-hexane(5mL) as eluent and methanol / acetic acid (V: V = 8:2) (6mL) as eluant.Compared three pre-treatment method including molecularly imprinted solid phase extraction (MISPE), solid-phase extraction (SPE) and matrix solid-phase dispersion (MSPD), the recoveries of enrofloxacin in chicken muscle were 82.37%, 70.24%, 82.43% detected by HPCE. The detection method of Enrofloxacin MISPE - HPCE of chicken muscle was established.The study indicates that the method of MISPE-HPCE has high selectivity, good precision, and the recovery rate has been up to the requirements of veterinary drug residue analysis. The method of eight kinds of veterinary drug residue was completed within 9 min by HPCE. The method is simple and rapid. It is of great both theoretical and practical significance to detecting eight kinds of veterinary drugs in animal-derived food, and ensuring people's health.