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The molecular imprinting technique is a new technology developed rapidly in recent years. Molecularly imprinted polymer (Molecularly Imprinted Polymer, MIP) has a high selectivity, chemical stability, etc., is a potential for development of solid-phase extraction material. The MIP and solid-phase extraction combined to form the molecularly imprinted solid phase extraction (Molecularly Imprinted Solid-Phase Extraction, MISPE), has a good prospect of application in the separation and detection of substances in drugs, food and biological samples. Chloramphenicol (chloramphenicol, CAP) is a broad-spectrum antibiotics, often used as animal feed additives. Due to improper use and metabolic incomplete, resulting in chloramphenicol residues in food of animal origin, there are serious side effects on the human body, and pose a threat to human health. The analysis of chloramphenicol residues in food is an important part of the food safety testing. Due to the low levels of chloramphenicol in food, complex sample matrix, so as to improve the selectivity and sensitivity of the analytical method has practical significance. Solid-phase extraction (SPE) is a method commonly used to improve selectivity, the key is the excellent performance of the solid-phase extraction material preparation. In this paper, CAP is the object, preparation of the CAP has specifically recognized and highly stable CAP imprinted polymer (Chloramphenicol based Molecularly Imprinted Polymer, CAPMIP). By optimizing the preparation conditions and molecular imprinted solid phase extraction conditions, the feed CAP detection. This article main conclusions: the CAP 1 template molecules, MAA as the functional monomer, prepared excellent performance through optimization of the template molecule with the monomer ratio, polymerization temperature, and the template molecule and a crosslinker ratio factors CAPMIP. The results show that: the template molecule, functional monomer with a cross-linking agent ratio of 1:4:24, the polymerization temperature of 60 ° C, the best of the adsorption of the prepared CAPMIP particles. 2. The preparation CAPMIP particles as solid phase extraction agent optimization activation, loading, washing and elution conditions are optimized solid-phase extraction conditions: 5 mL of methanol, 5 mL of acetonitrile and 5 mL of water induced MIP column; 2 mL of 10% of the ethanol solution as the sample solution; 3 mL of 20% acetonitrile solution as the eluent; 2 mL of acetonitrile as an eluent. Under this condition in of 1 ~ 15μmoL/LCAP recovery of 74.3 ~ 96.7%. MISPE can selectively identify and recovered quantitatively in a sample of CAP. Subcritical water extraction CAPMIP solid-phase extraction combined with detection of CAP in feed. The concentration of CAP 0.02,0.05,0.1 mol the / g spiked feed recoveries were 76.6%, 80.6% and 84.8%, respectively. Relative to pure subcritical water extraction, subcritical water extraction and MISPE extraction combined with HPLC detection better separation effect.
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