Cetyltrimethylammonium assay using fluorescence probe berberine and a competitive host-guest complexation with butylated β-cyclodextrin

An optical sensor for cetyltrimethylammonium chloride (CTAC), based on the fluorescence quenching of berberine/butylated β-cyclodextrin (HDB-β-CD) complex immobilized in plasticized poly(vinyl chloride) (PVC) membrane has been developed, in which berberine served as a sensitive fluorescence indicator probe. The decrease of fluorescence intensity of berberine/HDB-β-CD complex upon the addition of CTAC was attributed to the formation of an inclusion complex between HDB-β-CD and CTAC, which has been utilized as the basis of the fabrication of a CTAC-sensitive fluorescence sensor. The response mechanism of sensor has been discussed in detail. The analytical performance characteristics of the proposed CTAC-sensitive sensor were investigated. The sensor can be applied to the quantification of CTAC with a linear range covering from 7.0 × 10−11 to 4.0 × 10−9 mol L−1 with a detection limit of 3.0 × 10−11 mol L−1. The sensor exhibits excellent reproducibility, reversibility and selectivity. The recommended method was successfully used for the determination of CTAC in water samples.