Application of Chitosan/Alginate Nanocomposite Incorporated with Phycosynthesized Iron Nanoparticles for Efficient Remediation of Chromium

Abstract

Biopolymers and nanomaterials are ideal candidates for environmental remediation and heavy metal removal. As hexavalent chromium (Cr6+) is a hazardous toxic pollutant of water, this study innovatively aimed to synthesize nanopolymer composites and load them with phycosynthesized Fe nanoparticles for the full Cr6+ removal from aqueous solutions. The extraction of chitosan (Cht) from prawn shells and alginate (Alg) from brown seaweed (Sargassum linifolium) was achieved with standard characteristics. The tow biopolymers were combined and cross-linked (via microemulsion protocol) to generate nanoparticles from their composites (Cht/Alg NPs), which had a mean diameter of 311.2 nm and were negatively charged (−23.2 mV). The phycosynthesis of iron nanoparticles (Fe-NPs) was additionally attained using S. linifolium extract (SE), and the Fe-NPs had semispherical shapes with a 21.4 nm mean diameter. The conjugation of Cht/Alg NPs with SE-phycosynthesized Fe-NPs resulted in homogenous distribution and stabilization of metal NPs within the polymer nanocomposites. Both nanocomposites exhibited high efficiency as adsorbents for Cr6+ at diverse conditions (e.g., pH, adsorbent dose, contact time and initial ion concentration) using batch adsorption evaluation; the most effectual conditions for adsorption were a pH value of 5.0, adsorbent dose of 4 g/L, contact time of 210 min and initial Cr6+ concentration of 75 ppm. These factors could result in full removal of Cr6+ from batch experiments. The composited nanopolymers (Cht/Alg NPs) incorporated with SE-phycosynthesized Fe-NPs are strongly recommended for complete removal of Cr6+ from aqueous environments.

Enhancement of the Protective Activity of Vanillic Acid against Tetrachloro-Carbon (CCl4) Hepatotoxicity in Male Rats by the Synthesis of Silver Nanoparticles (AgNPs)

“…To ensure the synthesis of vanillic acid nanoparticles, an emergence of dark brown color in the vanillic acid solution following the addition of silver nitrate was formed indicating silver nanoparticle synthesis, while the solution stayed white without the addition of silver nitrate as shown in Supplementary Figure S1 (Supplementary Materials) [ 29 , 35 ].…”

“…The transmission electron microscope (TEM) image of the synthesized silver nanoparticles of vanillic acid is shown in Figure 2 . The AgNPs were spherical in shape and their size ranged from 11.0–14.1 nm [ 29 , 37 ]. The AgNPs’ structure is based on the electron plasmon oscillations of their free surface seen by the UV-Vis spectra, whereas the shape and size of their peaks in the spectra are ascribed to the surface plasmon resonance (SPR) peaks, and the presence of peaks at 450 nm indicates that there was no significant difference in the AgNPs’ size [ 35 , 37 ].…”

“…Applications of nanoparticle technology in the field of nanomedicine via nano-delivery systems has increased during the last decade where these nanoscale range materials are applied as diagnostic tools or delivery agents of therapeutic materials to the targeted sites under a precise scientific discipline [ 27 , 28 , 29 , 30 ]. Nanotechnology has helped in treating multiple chronic human diseases through the site-specific and target-oriented delivery of specific medicines [ 31 , 32 ].…”

Applications of Chitosan-Alginate-Based Nanoparticles—An Up-to-Date Review

“…Similarly, Almutairi et al [142] have studied the removal of hexavalent chromium (Cr 6+ ) from polluted water by the use of negatively charged (−23.2 mV) chitosan-alginate nanocomposites incorporated with iron NPs. High efficiency was reported, the optimum conditions for Cr 6+ adsorption being 5.0 pH, 4 g/L adsorbent dose, 210 min contact time, and 75 ppm initial Cr 6+ concentration.…”

Correction: Almutairi et al. Application of Chitosan/Alginate Nanocomposite Incorporated with Phycosynthesized Iron Nanoparticles for Efficient Remediation of Chromium. Polymers 2021, 13, 2481

“…The authors wish to make the following corrections to the published paper [ 1 ]. They should be as follows:…”