Electrochemical Sensor Based on Ionic Liquid Crystal Modified Carbon Paste Electrode in Presence of Surface Active Agents for Enoxacin Antibacterial Drug

A sensitive electrochemical sensor based on carbon paste and inclusion of ionic liquid crystal [(1-Butyl-1-methylpiperidinium hexafluorophosphate)] in presence of sodium dodecyl sulfate (ILCMCPE.....SDS) for the electrochemical determination of Enoxacin (EN) was prepared. Different ionic liquids were used and compared, namely (1-n-Hexyl-3-methyl imidazolium tetrafluoroborate) (ILMCPE1.....SDS) and (1-Butyl-4-methyl pyridinium tetrafluoroborate) (ILMCPE2.....SDS). The studied ionic liquids mimic cell membranes for their interaction with drug intake through cell membranes. We found that ILCMCPE.....SDS exhibited good electrochemical performances with higher conductivity and lower electron transfer resistance due to the combining effect of high ion conductivity, sensitivity, fast electron transfer, stability and antifouling ability of the ionic liquid crystal. SDS enhanced the preconcentration/accumulation of EN species in the ionic form at the surface. Excellent performance of ILCMCPE.....SDS for the determination of EN in the linear dynamic range of 6.67x10(-7) to 2.22x10(-5) mol L-1 with a correlation coefficient 0.9998 and LOD 3.28x10(-9) mol L-1. Simultaneous determination of binary mixtures dopamine/enoxacin and epinephrine/enoxacin was demonstrated with good peak potentials separations. This method was successfully applied for direct determination of EN in human urine samples with good recovery results. The ILCMCPE.....SDS showed also high reproducibility selectivity and anti -interference ability. (C) 2014 The Electrochemical Society. All rights reserved.