Indexed on: 09 Oct '07Published on: 09 Oct '07Published in: Analytical Chemistry
A novel highly selective sample cleanup procedure combining molecular imprinting and matrix solid-phase dispersion (MI-MSPD) was developed for the simultaneous isolation of ofloxacin, pefloxacin, norflorxacin, ciprofloxacin, and enrofloxacin in chicken eggs and swine tissues followed by high-performance liquid chromatography with fluorescence detection. The novel ofloxacin imprinted polymers synthesized in water-containing systems show high selectivity for the five fluoroquinolones in aqueous environment and the affinity can be easily adjusted by the pH of solution. Compared with conventional MSPD methods, using MIPs as selective MSPD sorbents, the five fluoroquinolones could be selectively extracted from a biological matrix and all matrix interferences were eliminated simultaneously. The average recoveries of the five fluoroquinolones were ranged from 85.7 to 104.6% for eggs and 86.8 to 102.7% for tissues with relative standard deviations of less than 7.0%. Detection limits for the identification of the five fluoroquinolones in eggs and tissues ranged from 0.05 to 0.09 ng/g.