A Ternary Nanocomposite Based on Nano-Bimetallic Platinum/Nickel Decorated on Multi-Walled Carbon Nanotubes for Flow Injection Amperometric Detection of Promethazine

Abstract

We propose a nano-bimetallic platinum/nickel composite on multi-walled carbon nanotubes (nano-Pt/Ni@MWCNT) composite as electrode material, which was prepared via a simple pyrolysis method followed by a mechanical ball-milling process. Results showed that the nano-Pt/Ni particles could be anchored on the surface of the MWCNT, which was confirmed by multiple characterizations. The nanostructure of the synthesized composite provides a large specific surface area to expose a large number of active sites and the resulting enhanced electrical conductivity ultimately improves the electrocatalytic activity towards promethazine (PMZ). Furthermore, a nano-Pt/Ni@MWCNT/GCE coupled flow-injection amperometric system was used to electrochemically determine PMZ. The proposed sensor also demonstrated potential in analysis in cases involving a large number of samples, which can be rapid analysis with a high sample throughput of around 60 samples h−1. Linearity of response was shown from 0.10 to 100 μM and from 100 to 1000 μM PMZ. The detection limit was 0.03 μM and the limit of quantification was 0.11 μM. The proposed method demonstrated excellent reproducibility (RSD = 1.02%, n = 6), repeatability (RSD = 1.44%, n = 25), operational stability (RSD = 2.02%, n = 100), and interference tolerance. The viability of the nano-PtNi@MWCNT/GCE was demonstrated for the detection of PMZ in spiked saliva, urine, and beverage samples, with recoveries from 95.7 ± 0.7 to 105 ± 2%.