Design of a Novel Nanosensors Based on Green Synthesized CoFe2O4/Ca-Alginate Nanocomposite-Coated QCM for Rapid Detection of Pb(II) Ions

Abstract

Pb(II) is a significant contaminant that is known to have negative effects on both humans and animals. Recent industrial operations have exacerbated these consequences, and their release of several contaminants, including lead ions, has drawn attention to the potential effects on human health. Therefore, there is a lot of interest in the rapid, accurate, and selective detection of lead ions in various environmental samples. Sensors-based nanomaterials are a significant class among the many tools and methods developed and applied for such purposes. Therefore, a novel green synthesized cobalt ferrite (CoFe2O4) nanoparticles and functionalized CoFe2O4/Ca-alginate nanocomposite was designed and successfully synthesized for the fabrication of nanoparticles and nanocomposite-coated quartz crystal microbalance (QCM) nanosensors to detect the low concentrations of Pb(II) ions in the aqueous solutions at different temperatures. The structural and morphological properties of synthesized nanoparticles and nanocomposite were characterized using different tools such as X-ray diffraction (XRD), N2 adsorption–desorption isotherm, dynamic light scattering (DLS), zeta potential analyzer (ζ-potential), atomic force microscopy (AFM), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy-dispersive X-ray spectroscopy (EDX). The QCM results revealed that the green synthesized CoFe2O4 nanoparticles and functionalized CoFe2O4/Ca-alginate nanocomposite-coated QCM nanosensors exhibited high sensitivity, stability, and rapid detection of Pb(II) ions in the aqueous solutions at different temperature. The lowest detection limit for Pb(II) ions in the aqueous solutions could reach 125 ng, which resulted in a frequency shift of 27.49 ± 0.81, 23.63 ± 0.90, and 19.57 ± 0.86 Hz (Δf) for the QCM detector coated with green synthesized CoFe2O4 nanoparticles thin films, and 25.85 ± 0.85, 33.87 ± 0.73, and 6.87 ± 0.08 Hz (Δf) for the QCM detector coated with CoFe2O4/Ca-Alg nanocomposite thin films in a real-time of about 11, 13, and 13 min at 25 °C, 35 °C, and 45 °C, respectively. In addition, the resonance frequency change results showed the superiority of functionalized CoFe2O4/Ca-alginate nanocomposite coated QCM nanosensor over CoFe2O4 nanoparticles towards Pb(II) ions detecting, which attributed to the beneficial properties of alginate biopolymer.

Chitosan neem nanocapsule enhances immunity and disease resistance in nile tilapia (Oreochromis niloticus)

“…A similar preparation method to the aqueous extract of Ocimum basilicum using the chitosan nanocapsule has been investigated [ 28 ]. The CNNC was characterized using several techniques [ 47 ], which confirmed the synthesis process of the nano form. The XRD pattern in this study confirmed the amorphous nature of CNNC with a good coating of neem extract by the chitosan nanocapsule.…”

Recent advancements in nano sensors for air and water pollution control

“…Functional N-and S-co-doped carbon dots for detection of trace amounts of Fe 3+ with detection limit as low as 1.72 nM were reported by Cui et al, 140 Nitrogen-doped graphene quantum dots (N-GQD) for portable detection of Fe 3+ were introduced by Yao et al, 141 The N-GQD showed high production yield of 64% and high blue fluorescence providing a new strategy for controlling Fe3+ levels in environmental water. Functionalized CoFe 2 O 4 /Ca-alginate nanocomposite was designed by Al-Gethami et al, 142 as nanosensor for detection of Pb 2+ ions in aqueous solutions at different temperatures. High sensitivity, stability, and rapid detection are among the reported properties of the proposed sensor, while the lowest detection limit for Pb 2+ ions could reach 125 ng.…”

Poly(O‐Toluidine)‐polyvinylpyrrolidone copolymer submerged MgFe2O4/CS‐OXSWCNTs nanocomposite for removal of acid red dye from aqueous solutions

“…To treat wastewater, numerous environmentally friendly and physicochemical techniques have been developed, such as filtration, adsorption, chemical degradation, biodegradation, photodegradation, and precipitation. [15][16][17][18] Among these methods, physical adsorption processes are considered reliable due to their efficiency and simplicity of operation and preparation. They are often preferred as they offer a cost-effective approach to water treatment.…”

“…Consequently, it is crucial to implement necessary measures to reduce water contamination caused by dye effluents. To treat wastewater, numerous environmentally friendly and physicochemical techniques have been developed, such as filtration, adsorption, chemical degradation, biodegradation, photodegradation, and precipitation 15–18 . Among these methods, physical adsorption processes are considered reliable due to their efficiency and simplicity of operation and preparation.…”