Nicotine derivative optode membrane with nonactin as ionophore

Plasticised poly(vinyl chloride) optode membrane incorporated with nonactin as ionophore, ETH 5294 as H⁺-selective chromoionophore and potassium tetrakis(4-chlorophenyl)borate as anionic site, was used as a reversible sensing device for indirect determination of nicotine. Nicotine was extracted from cigarette samples and converted to its bromoethane derivative (ND⁺Br⁻) by reacting with a solution of bromoethane in ethanol. ND⁺Br⁻, in a solution of Tris (hydroxymethyl)aminomethane–HCl buffer, was extracted into the bulk of the optode membrane and subsequently caused changes in optical absorption of the sensing layer. The pH effect, response mechanisms, response behaviour, response time, dynamic working range, detection limit, sensitivity and selectivity were discussed in detail.