A bio-inspired sensor based on surfactant film and Pd nanoparticles.

A bio-inspired complex, [(bpbpmp)Fe(III)(m-OAc)(2)Cu(II)](ClO(4)), was combined with a zwitterionic surfactant (ImS3-14) stabilizing pre-formed palladium nanoparticles and coated on a glassy carbon electrode (GCE). This bio-inspired surfactant film was capable of catalyzing redox reactions of dihydroxybenzenes, thus allowing the simultaneous electrochemical quantification of CC and HQ in cigarette residue samples by square-wave voltammetry (SWV). The best experimental conditions were obtained using phosphate buffer solution (0.1 mol L(-1), pH 7.0), with 1.3 nmol of the bio-inspired complex, 0.15 μmol of the surfactant and 1.08 nmol of Pd. The best voltammetric parameters were: frequency 100 Hz, pulse amplitude 40 mV and step potential 8 mV. The limits of detection calculated from simultaneous curves were found to be 2.2 × 10(-7) and 2.1 × 10(-7) mol L(-1) for HQ and CC respectively.