Electrochemical Characterization and Detection of Lead in Water Using SPCE Modified with BiONPs/PANI

Abstract

The need for constant assessment of river water qualities for both aquatic and other biological survival has emerged a top priority, due to increasing exposure to industrial pollutants. A disposable screen print carbon electrode was modified with a conductive polymer (PANI) and Zn and/or Cu oxides NPs, obtained through bioreduction in citrus peel extracts (lemon and orange), for ultra-sensitive detection of PB2+, in the Crocodile River water sample. The synthesized materials were characterized with Fourier-transform infra-red spectroscopy (FTIR), ultra-violet visible spectroscopy (UV-Vis), and scanning electron microscopy (SEM). The SPC-modified electrodes designated as SPCE/LPE/BiONPs/PANI and SPCE/OPE/BiONPs/PANI were characterized using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) and eventually deployed in the electrochemical detection of PB2+ in water using square wave voltammetry (SWV) technique. The electrochemical responses of the modified electrodes for both CV and EIS in 0.1 M HCl demonstrated enhanced performance relative to the bare SPCE. A detection and quantification limit of 0.494 ppb and 1.647 were obtained at SPCE/LPE/BiONPs/PANI, respectively, while a detection and quantification limit of 2.79 ppb and 8.91 ppb, respectively, were derived from SPCE/OPE/BiONPs/PANI. The relative standard deviations (RSD) for SPC electrode at a 6.04 µM PB2+ analyte concentration was 4.76% and 0.98% at SPCE/LPE/BiONPs/PANI and SPCE/LPE/BiONPs/PANI, respectively. The effect of copper, zinc, iron, cobalt, nickel, and magnesium on the stripping peaks of PB2+ at SPCE/OPE/BiONPs/PANI, showed no significant change except for cobalt, with about 17.67% peak current drop. The sensors were assessed for possible determination of PB2+ in spiked river water samples. The average percentage recovery and RSD calculated were 94.25% and 3.74% (n = 3) at SPCE/LPE/BiONPs/PANI and, 96.70% and 3.71% (n = 3) at SPCE/OPE/BiONPs/PANI, respectively. Therefore, the fabricated sensor material could be used for environmental assessment of this highly toxic heavy metal in the aquatic system

Study of graphene incorporation into ZnO-PVA nanocomposites modified electrode for sensitive detection of cadmium

“…In this study, cadmium detection was conducted using GCE as electrode and SWV as detection method. Determining the potential range was crucial for studying cadmium detection, with the potential range typically falling within −1.2 V to −0.1 V [ 29 ]. Since GCE was used as electrode, attention was paid to the connection from the potentiostat to GCE and the speed of nitrogen purge.…”

“…In electrochemical detection, a supporting electrolyte is used to reduce solution resistance and maintain consistent ionic strength [ 12 ]. Several electrolytes such as acetic acid, potassium chloride, sodium chloride, phosphate buffer, and hydrogen chloride are considered the best choices for electrolytes in electrochemical detection [ 13 ]. Additionally, the use of a glassy carbon electrode (GCE) is common in heavy metal detection due to its low background current, wide potential range, and ease of use [ 14 ].…”

Transport of Nanoparticles into Plants and Their Detection Methods

“…Mechanical properties at the bulk level are characterized by atomic force microscopy (AFM) and dynamic mechanical analysis (DMA) [ 136 ]. In contrast, AFM-based nanoindentation and scanning probe microscopy (SPM) are the techniques commonly used to characterize at the nanoscale level [ 137 ], and techniques used to characterize electrical properties at the bulk level are impedance spectroscopy and four-point probe measurement [ 138 ]. On the other hand, techniques used to characterize at the nanoscale level are conductive AFM (cAFM), Kelvin probe force microscopy (KPFM), and transmission electron microscopy (TEM) with energy-dispersive X-ray spectroscopy (EDS) [ 139 ].…”

A Sensitive and Selective Non-Enzymatic Dopamine Sensor Based on Nanostructured Co3O4–Fe2O3 Heterojunctions

“…In recent times, screen-printed carbon electrode (SPCE) electrochemical sensors have been largely used in different fields such as in medicine, the environment and so on [10,11]. The SPCE based on heterostructures and nano-heterojunction derivatives that are based on metal oxides (MOs) has received great interest.…”