Detection of quinoline using ammonia plasma-functionalised multi-walled carbon nanotubes and application to real samples

Abstract

Study on the growth of multi-walled carbon nanotubes (MWCNT) using plasma-enhanced chemical vapour deposition (PECVD) techniques has been carried out in this work. MWCNT screen-printed electrode (SPCE) based on silicon substrate was fabricated for quinoline detection using photolithography methods. The MWCNT working electrodes were modified under ammonia (NH3) plasma to enhance the surface sensitivity to detect quinoline. The electrocatalytic activity of modified electrode towards oxidation of quinoline was evaluated using cyclic voltammetry (CV) and linear sweep voltammetry (LSV). Under experimental conditions, peak currents increased with an increase in the concentration of quinoline (dynamic range = 2.0 to 25.0 µM) and displayed good linearity (R2 = 0.9958). The limit of detection (LOD) was calculated to be 0.164 µM. The modified electrode was then applied to real samples sourced from both healthy and Ganoderma boninense infected oil palm roots crude extracts. A linear plot was obtained with a good linearity (R2 = 0.9879), indicating good sensing results. E IN PR.