Determination of butylparaben by adsorptive stripping voltammetry at glassy carbon electrodes modified with multi-wall carbon nanotubes

This work reports on the performance of glassy carbon electrodes (GCE) modified with a layer of multi-wall carbon nanotubes (MWCNTs) for the determination of butylparaben (BP) by adsorptive stripping voltammetry (AdSV). Several operating conditions and voltammetric parameters were examined. Under the chosen conditions, BP peak current obtained by differential pulse voltammetry increased linearly with BP concentration up to 100 μM with a limit of detection of 0.2 μM. A molecularly imprinted solid-phase extraction procedure (MISPE) was developed to improve the sensitivity and selectivity of BP electroanalysis when applied to real samples. The proposed methodology was successfully used for the quantification of BP in spiked water samples with recovery values between 82 and 85%. The MISPE procedure allowed the detection of BP at concentration levels of 0.02 μM in the presence of potential interfering substances such as 2,4,6-trichlorophenol (TPC), atrazine, paracetamol or diclofenac.