Rapid electrochemical platform for nicotine sensing in cigarettes and chewing gums
Kristína Cinková *, Linda Dianová, Marian Vojs a, Marián Marton b, Ľubomír Švorc
Institute of Analytical Chemistry, Faculty of Chemical and Food Technology, Slovak University of Technology in Bratislava, Radlinského 9, SK-812 37 Bratislava, Slovak Republic
a Institute of Electronics and Photonics, Faculty of Electrical Engineering and Information Technology, Slovak University of Technology in Bratislava, Ilkovičova 3, SK-812 19 Bratislava, Slovak Republic
b Institute of Electronics and Photonics, Faculty of Electrical Engineering and Information Technology, Slovak University of Technology in Bratislava, Ilkovičova 3, SK-812 19 Bratislava, Slovak Republic
E-mail: * kristina.cinkova@stuba.sk
Abstract: A novel protocol for the simple and rapid determination of nicotine using square-wave voltammetry at boron-doped diamond electrode was developed. The effect of pH of supporting electrolyte, scan rate and square-wave voltammetric parameters was examined. Behavior study revealed that nicotine provided two irreversible oxidation peaks, the first one well-shaped at +1.14 V and the second one poorly-defined at +1.61 V vs. Ag/AgCl electrode in the presence of phosphate buffer (pH 9.0). Under optimal experimental conditions (modulation amplitude of 40 mV, frequency of 50 Hz and scan rate of 0.225 V s-1), the current response of nicotine was proportionally linear in the concentration range from 9.9 × 10-6 to 1.7 × 10-4 mol L-1 (R2 = 0.996) with the detection limit of 6.1 × 10-6 mol L-1 (0.989 mg L-1) and the relative standard deviation of 8.8% (number of measurements n = 10, 5.7× 10-5 mol L-1 nicotine). The proposed procedure was applied to the quantification of nicotine in cigarettes and chewing gums with the determined values in good agreement with those declared by producer. In this respect, the developed protocol could represent an effective and rapid alternative to chemically modified electrodes in analysis of alkaloids.
Keywords: nicotine, boron-doped diamond electrode, square-wave voltammetry, detection limit
Full paper in Portable Document Format: acs_0226.pdf
Acta Chimica Slovaca, Vol. 8, No. 2, 2015, pp. 166—171, DOI: 10.1515/acs-2015-0028