Analytical Sciences


Abstract − Analytical Sciences, 29(3), 339 (2013).

Potential of Capillary Electrophoresis (CE) and Chip-CE with Dual Detection (Capacitively-Coupled Contactless Conductivity Detection (C4D) and Fluorescence Detection) for Monitoring of Nicotine and Cotinine Derivatization
Nantana NUCHTAVORN,*1,*2 Marketa RYVOLOVA,*3 Fritz BEK,*4 Mirek MACKA,*5 Chutima PHECHKRAJANG,*2 and Leena SUNTORNSUK*2
*1 Faculty of Pharmacy, Siam University, 235 Petkasem Rd., Phasicharoen, Bangkae, Bangkok 10160, Thailand
*2 Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Mahidol University, 447 Sri-Ayudhaya Rd., Rajathevee, Bangkok 10400, Thailand
*3 National Centre for Sensor Research, Irish Separation Science Cluster and School of Chemical Sciences, Dublin City University, Dublin 9, Ireland
*4 Agilent Technologies, P.O. Box 1280, 76337 Waldbronn, Germany
*5 Australian Centre for Research on Separation Science, School of Chemistry, University of Tasmania, Private Bag 75, Hobart, Tasmania 7001, Australia
Capillary electrophoresis (CE) coupled with capacitively-coupled contactless conductivity (C4D) and fluorescence (FD) detectors and chip-CE for monitoring of nicotine and cotinine derivatization was demonstrated. Separation of the substrates and intermediates could be achieved by CE-C4D in 7 min (Rs > 2.7) using 45 mM acetic acid (pH 3.0) and this system was applied to detect the intermediate formation. Final fluorescent products could be analyzed by micellar electrokinetic chromatography (MEKC-FD) in 5 mM borate buffer (pH 9.0) containing 10 mM sodium dodecylsulfate (SDS) (%RSD < 3.00%). Transferring of MEKC-FD to chip-CE allowed for shorter analysis time (2.5 min) and decreased sample consumption. The chip-CE-FD shows good detection and quantitation limits (< 7.5 μM) and precision (%RSD < 2.81%) and was employed to determine nicotine and cotinine in artificial urine. This work reveals the potential of CE and chip-CE with dual detectors as simultaneous, convenient and rapid methods for monitoring pyridine derivatization.