Carbon-nanotube amperometric sensor for selective determination of 4-chloroaniline in commercial chlorhexidine solutions

Autor: Vagner Bezerra dos Santos, Denis Tadeu Rajh Vidal, Rodrigo H. O. Montes, Ana P. Lima, Rodrigo A.A. Munoz, Eduardo M. Richter, Claudimir Lucio do Lago
Rok vydání: 2016
Předmět:
Zdroj: Repositório Institucional da USP (Biblioteca Digital da Produção Intelectual)
Universidade de São Paulo (USP)
instacron:USP
ISSN: 0925-4005
DOI: 10.1016/j.snb.2016.02.139
Popis: This work reports a carbon-nanotube amperometric sensor for the selective determination of 4-chloroaniline (4-CLA), the major degradation product found in commercial chlorhexidine solutions. The harmful 4-CLA is detected on a multi-walled carbon nanotube (MWCNT)-modified electrode, free from the interference of chlorhexidine and other substances present in such samples, with a detection limit of 50 nmol L −1 . MWCNTs of two different dimensions were evaluated for 4-CLA detection and a 3-fold increase in sensitivity using both modified electrodes was obtained in comparison with the bare electrode. The association of batch-injection analysis with the amperometric detection provided high precision (1.2%) and sample throughput (130 h −1 ). Analyses of samples by capillary electrophoresis-tandem mass spectrometry (CE-MS/MS) attested the accuracy of the proposed method. Mouth rinse and skin disinfectant samples presented 4-CLA concentrations in the range between 4 and 235 μmol L −1 .
Databáze: OpenAIRE