Abstract

Determination of Cetylpyridinium Chloride Employing a Sensitive Fluorescent Probe

Author(s): Jian-Hong X, Lin S, Li-Ming D, Cai-Ping C, Hao W and Yin-Xia C

The fluorescence quenching of cucurbit[7]uril-palmatine(CB[7]-PAL) complexes by cetylpyridinium chloride (CPC) has been studied in aqueous solutions. The results show that the rate of the fluorescence quenching was proportional to the concentration of CPC. A fluorescent probe method of simply, accurately and high sensitivity was developed for the determination of CPC in pharmaceutical preparations and human urine through the supramolecular complex formation with CB[7]. The linear range of the method was from 0.019 μg mL−1 to 3.556 μg mL−1, with a detection limit of 0.007 μg mL−1. Molecular modelling of the interaction between CPC and CB[7] was established and was also confirmed by 1 H NMR. This paper also discusses the mechanism of fluorescence for the indicator probes. This shows that the proposed method has the potential for therapeutic monitoring, pharmacokinetics and clinical applications.