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

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 & mu;M and from 100 to 1000 & mu;M PMZ. The detection limit was 0.03 & mu;M and the limit of quantification was 0.11 & mu;M. 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 & PLUSMN; 0.7 to 105 & PLUSMN; 2%.