Impedimetric immunosensor for the specific label free detection of ciprofloxacin antibiotic

7 pages, 6 figures.-- PMID: 17826084 [PubMed].-- Printed version published on Nov 30, 2007.Impedance spectroscopy approaches combined with the immunosensor technology have been used for the determination of trace amounts of ciprofloxacin antibiotic belonging to the fluoroquinolone family. The sensor electrode was based on the immobilization of anti-ciprofloxacin antibodies by chemical binding onto a poly(pyrrole-NHS) film electrogenerated on a solid gold substrate. The electrode surface was modified by electropolymerization of pyrrole-NHS, antibody grafting and ciprofloxacin immunoreaction. The sensitive steps of surface modification, cyclic voltammetry (CV) and atomic force microscopy (AFM) imaging have been used for electrode surface characterization.The immunoreaction of ciprofloxacin on the grafted anti-ciprofloxacin antibody directly triggers a signal via impedance spectroscopy measurements which allows the detection of extremely low concentration of 10 pg/ml ciprofloxacin.The authors thank the Commission of the European Communities Research Directorate for their support in the framework of the ELISHA project no. NMP-A-CT-2003-505485-1. Drs. S. Cosnier, C. Martelet and N. Jaffrezic-Renault would like to thank the GDR CNRS 2619 “Microbiocapteurs” for partial support. Work performed at AMRg-CSIC was partially funded by the Spanish Ministry of Education and Science (contract numbers AGL2005-07700-C06-01). The AMR group is a consolidated Grup de Recerca de la Generalitat de Catalunya and has support from the Departament d’Universitats, Recerca i Societat de la Informació de la Generalitat de Catalunya (expedient 2005SGR 00207).Peer reviewe