Simple One-Step Synthesis of Bismuth Nanoparticles for Voltammetric Sensing of Metal Ions

This study describes a simple and rapid bismuth nanoparticles (BiNPs) synthesis performed at room temperature and alkaline medium. A natural product such honey was used as a stabilizing agent. The nanoparticles were characterized with UV-Vis spectroscopy, transmission electron microscopy, zeta potential and X-ray diffraction and electrochemistry. The average size of the BiNPs were smaller than 4 nm. A glassy carbon electrode was modified with the bismuth nanoparticles by drop-casting technique showing an excellent adhesion on the electrode surface that allows several consecutive measurements. The voltammetric study of the modified electrode was carried out using Square Wave Anodic Stripping Voltammetry technique (SWAV) to quantify lead and cadmium. The SWAV parameters were optimized by Box-Behnken experimental design combined with a desirability function. The concentration ranges were 1.0 to 30.0 mu g L-1 for lead and 2.0 to 30.0 mu g L-1 for cadmium, and the detection limits (LDD) were 0.73 mu g L-1 and 1.81 mu g L-1 for lead and cadmium respectively. Water samples from the Colorado River, Argentina, were analyzed and the obtained recovery values were between 105.3-106.7% (Pb) and 88.6-102.9% (Cd). The proposed method is suitable for the determination of metals in water samples due to its versatility. Moreover, it is fast and low cost.