Preparation of mixed-templates molecularly imprinted polymers and investigation of the recognition ability for tetracycline antibiotics

We developed in the present study a set of molecularly imprinted polymers (MIPs) by precipitation polymerization, using four members of tetracycline antibiotics (TCs) as templates (Oxytetracycline, Tetracycline, Chlortetracycline and Doxycycline). Then, based on the imprinting effect of different MIPs (TCs), Oxytetracycline and Chlortetracycline were chosen as mixed-templates to synthesize high selective MIPs for recognition of a family of analytes. And the characterization of obtained MIPs was analyzed by FESEM analysis, Brunauer–Emmett–Teller (BET) method, polymer size analysis, and determination of swelling ratio and COOH capacity. It was shown that the optimal imprinting factors of TCs on mixed-templates MIPs were more than 6.0 and the maximum binding amount of TCs were about 27 μmol g−1 (Oxytetracycline), 35 μmol g−1 (Tetracycline), 35 μmol g−1 (Chlortetracycline) and 39 μmol g−1 (Doxycycline), respectively. Finally, the mixed-templates MIPs were shown to be promising for on-line solid-phase extraction-HPLC-UV determination of trace TCs in foodstuffs. With a sample loading volume of 10 mL, the enhancement factors were in the range of 159–410.