Electrode modified with nitrogen-doped graphene quantum dots supported in chitosan for triclocarban monitoring

Abstract Triclocarban is an antimicrobial agent frequently used in personal care products with potential activity for endocrine disrupting, and hence its monitoring is particularly important. A sensitive analytical tool was developed for electroanalysis of triclocarban through modifying a glassy carbon substrate with nitrogen-doped graphene quantum dots immobilized in chitosan. Electron microscopy results showed that the synthesized quantum dots had a diameter of 4.5 nm. The doping with nitrogen in the graphene matrix was confirmed by spectroscopic techniques. Electrochemical techniques showed excellent triclocarban oxidation current responses provided by the modified electrode compared to the bare electrode. The calibration plot for triclocarban was constructed in 0.1 mol L−1 phosphate buffer (pH 7.0):ethanol (95:5 v/v) in the range of 0.05 to 8.0 μmol L−1 with limits of detection and quantification of 17.0 and 57.0 nmol L−1, respectively. The modified electrode was effectively implemented in the quantification of triclocarban in personal care products with recoveries data in the range of 90 to 109%. Furthermore, the modified electrode was applied in the simultaneous determination of triclosan (+0.60 V) and triclocarban (+0.95 V) with limits of detection of 14.0 and 21.0 nmol L−1, respectively. The application was carried out in surface water samples with excellent accuracy indicated by recovery data in the range of 93 to 110%.