Preparation of Molecularly Imprinted Polymer Monolith with an Analogue of Thiamphenicol and Application to Selective Solid-Phase Microextraction

A molecularly imprinted polymer (MIP) monolith has been prepared and characterized. Its application to the assay of thiamphenicol in milk with high-performance liquid chromatography-photodiodes array detector was validated. The newly developed MIP monolith was produced using an analogue to thiamphenicol as the template molecule to avoid major traditional drawback associated with MIPs of residual template bleeding. The MIP monolith synthesized in a micropipette tip could be connected with syringes in different sizes simply to perform solid-phase microextraction process without any other treatment. This molecularly imprinted polymer monolith microextraction (MIPMME) method showed high selectivity and enrichment ability for thiamphenicol (TAP). Several parameters affecting MIPMME were investigated, including the flow rate, volume, pH and salt concentration of sample, the type and volume of washing solution, and the type and flow rate of eluent. The recovery of this method for TAP was investigated and high recoveries of 93.5 similar to 96.8% from milk were obtained with relative standard deviations less than 6.3%.