APPLICATION OF GLASSY CARBON ELECTRODE MODIFIED WITH NAFION/MWCNTS FOR SENSITIVE VOLTAMMETRIC DETERMINATION OF THYMOL

The glassy carbon electrode modified with Nafion and multi-walled carbon nanotubes (Nafion/MWCNTs), applied for the determination of thymol using differential pulse voltammetry in phosphoric acid and methanol is presented. The calibration graph obtained for thymol is linear from 0.5 mu M (75 mu g/L) to 5 mu M (750 mu g/L) for a preconcentration time of 15 s, with correlation coefficient of 0.998. For a GC-Nafion/MWCNTs electrode the detection limit for a preconcentration time of 30 s is as low as 7.5 mu g/L. The repeatability of the method at a concentration level of the analyte as low as 75 mu g/L. expressed as RSD is 3.9% (n = 5). The proposed method was successfully applied and validated by studying the recovery of thymol from urine, dental mouthwash and liquid anti-ace.