Xanthan gum-based copper nano-magnetite doped carbon aerogel: A promising candidate for environmentally friendly catalytic dye degradation

Unlocking the potential of plant gums: Bioinformatics-driven insights into green synthesis and applications of metal-based nanoparticles

Plant gums (PGs) are naturally occurring heteropolysaccharides that exude from different plants, typically from their stems, bark, and seeds. They are non-toxic, biodegradable, biocompatible, and cost-effective. PGs are commonly used as emulsifiers, stabilizers, and thickeners in the pharmaceutical, food, and cosmetics industries. Chemically, they are composed of complex sugars, with minor components including proteins, minerals, and flavonoids. Owing to their diverse phytochemical profiles, they have been comprehensively studied over the last couple of decades as reducing, capping, and stabilizing agents for the synthesis of metallic nanoparticles (NPs). Researchers have synthesized various eco-friendly metallic NPs from PGs for potential applications in environmental, industrial, and pharmaceutical domains. This review thoroughly covers the synthesis, characterization techniques, and diverse applications of PG-based metallic NPs. For the first time, using advanced informatics tools like PubChem, ChemSpider, and SwissADME, this study provides novel insights into the molecular interactions and stabilization of PG-based NPs. The review also analyzes the diverse composition of PGs and explores the unique reducing and capping potential of their phytochemicals in the green synthesis of metallic NPs. It also examines the potential drawbacks and proposes possible solutions related to PG-based metallic NP synthesis, along with discussing the future prospects of these nanomaterials.

Unveiling the impact of dyes on aquatic ecosystems through zebrafish - A comprehensive review

Dye industry plays an essential role in industrial development, contributing significantly to economic growth and progress. However, its rapid expansion has led to significant environmental concerns, especially water pollution and ecosystem degradation due to the discharge of untreated or inadequately treated dye effluents. The effluents introduce various harmful chemicals altering water quality, depleting oxygen levels, harming aquatic organisms, and disrupting food chains. Dye contamination can also persist in the environment for extended periods, leading to long-term ecological damage and threatening biodiversity. Therefore, the complex effects of dye pollutants on aquatic ecosystems have been comprehensively studied. Recently, zebrafish (Danio rerio) has proved to be an effective biomedical model for this study due to its transparent embryos allowing real-time observation of developmental processes and genetic proximity (approx. 87%) to humans for studying diverse biological responses. This review highlights the various toxicological effects of industrial dyes, including cardiovascular toxicity, neurotoxicity, genotoxicity, hepatotoxicity, and developmental toxicity. These effects have been observed at different developmental stages and dye concentrations in zebrafish. The review underscores that the structure, stability and chemical composition of dyes significantly influence toxicological impact, emphasizing the need for detailed investigation into dye degradation to better understand and mitigate the environmental and health risks posed by dye pollutants.

Synthesis of zinc oxide semiconductor nanoparticles using natural extract: a systematic evaluation of cationic dye photodegradation influenced by extract concentration, catalyst dose, and pH

This work obtained zinc oxide nanoparticles (ZnO NPs) using organic components extracted from Waltheria americana at different concentrations. ZnO materials were subsequently applied in the photodegradation of two cationic dyes, Rhodamine B (RB) and methylene blue (MB), at different doses of catalyst and pH. The crystallinity and hexagonal Wurtzite structure of ZnO were established through XRD analysis. The Zn-O bond in the ZnO NPs was confirmed in the FTIR, with the characteristic signals observed in the fingerprint region at ~ 400 cm-1. SEM and TEM revealed the formation of quasi-spherical particles with an average size ranging from 2 to 12 nm, depending on extract concentrations during synthesis. UV-Vis studies indicated the optical bandgap of ZnO, with values below 3 eV, also dependent on extract concentration. PL analysis revealed the recombination of free excitons and defects in ZnO. Photocatalytic studies of ZnO materials demonstrated excellent degradation efficiency of RB and MB dyes, which was influenced by the extract concentration of NPs, while the degradation of MB was enhanced with a 1:1 dye-to-catalyst ratio under acidic conditions. In contrast, due to RB more complex structure, an increased ratio of 1:1 to 1:3 and acidic pH conditions improved its degradation. Green-synthesized ZnO NPs using photocatalysis techniques exhibit significant potential as eco-friendly alternatives for removing contaminants from water.

Atomically dispersed single-atom catalysts (SACs) and enzymes (SAzymes): synthesis and application in Alzheimer's disease detection

Alzheimer's disease (AD) is a progressive neurodegenerative disorder characterized by cognitive decline and memory loss. Conventional diagnostic methods, such as neuroimaging and cerebrospinal fluid analysis, typically detect AD at advanced stages, limiting the efficacy of therapeutic interventions. Early detection is crucial for improving patient condition by enabling timely administration of treatments that may decelerate disease progression. In this context, single-atom catalysts (SACs) and single-atom nanozymes (SAzymes) have emerged as promising tools offering highly sensitive and selective detection of Alzheimer's biomarkers. SACs, consisting of isolated metal atoms on a support surface, deliver unparalleled atomic efficiency, increased reactivity, and reduced operational costs, although certain challenges in terms of stability, aggregation, and other factors persist. The advent of SAzymes, which integrate SACs with natural metalloprotease catalysts, has further advanced this field by enabling controlled electronic exchange, synergistic productivity, and enhanced biosafety. Particularly, M-N-C SACs with M-Nx active sites mimic the selectivity and sensitivity of natural metalloenzymes, providing a robust platform for early detection of AD. This review encompasses the advancements in SACs and SAzymes, highlighting their pivotal role in bridging the gap between conventional enzymes and nanozyme and offering enhanced catalytic efficiency, controlled electron transfer, and improved biosafety for Alzheimer's detection.

Chitosan-loaded biogenic silver nanocomposite for photocatalytic remediation of dye pollutants and antibacterial activity

The release of industrial wastewater has adverse effects on both aquatic ecosystems and the environment. Discharging untreated organic dyes into aquatic environments significantly amplifies pollution levels in these ecosystems. Ensuring the appropriate disposal of organic colorants and their derivatives before introducing them into wastewater streams is essential to prevent environmental contamination. This study aimed to develop an eco-friendly and sustainable approach to synthesize a chitosan-functionalized silver (Ag) nanocomposite using Solanum trilobatum for color pollutant mitigation. The synthesized CS-Ag nanocomposite was analyzed using various techniques such as UV-visible, FTIR, TEM, and EDS. TEM analysis revealed that the CS-Ag nanocomposite had a spherical nanostructure, with diameters ranging from 17.4 to 43.9 nm. These nanocomposites were tested under visible light irradiation to analyze their photocatalytic character against Congo red (CR). The nanocomposite exhibited a remarkable dye removal efficiency of over 93.6% within 105 min under irradiation. In the experimental recycling study, the CS-Ag nanocomposites demonstrated remarkable stability and reusability. Furthermore, the CS-Ag nanocomposite exhibited promising inhibition activity against bacterial pathogens. Our research revealed that the synthesized nanocomposite has the potential to act as a highly effective photocatalyst and bactericidal agent in various industrial and clinical applications.

Nickel-doped magnetic carbon aerogel derived from xanthan gum: a competent catalyst for the degradation of single and binary dye-based water pollutants

Toxic organic dyes (colorants) are one of the main causes of water pollution that releases destructive effluents in the environment. To overcome this issue, a fundamental need to produce a novel, efficient catalyst for the degradation and mineralization of dye mixtures has arisen. The objective of this research is to develop an eminent Ni-doped magnetic carbon aerogel (Ni-MCA) catalyst using graft co-polymerization method having xanthan gum as backbone doped with Ni-magnetic nanoparticles (Ni-MNPs), that do not show agglomeration and easy to separate. The examination revealed that Ni-MCA provided exceptional magnetic characteristics (Ms = 52.75 emu/g) and potent catalytic activity for the degradation of mono- as well as binary-dye solutions of Congo red (CR) and methyl green (MG) dyes. The formation was verified by various characterization techniques such as FTIR, VSM, XRD, XPS, SEM, TEM, and EDX mapping. Interestingly, Ni-MCA shows faster result on anionic dye CR up to 97% with degradation rate of 5.647 × 10-1 min-1, and MG dye shows degradation of 95.7% with the degradation rate of 2.169 × 10-1 min-1, while dye mixture is showing 90% degradation with rate of 2.159 × 10-1 min-1.

Bryophyte-Bioinspired Nanoporous AAO/C/MgO Composite for Enhanced CO2 Capture: The Role of MgO

A composite material composed of anodized aluminum oxide (AAO), carbon (C), and magnesium oxide (MgO) was developed for CO2 capture applications. Inspired by the bryophyte organism, the AAO/C/MgO composite mirrors two primary features of these species-(1) morphological characteristics and (2) elemental composition-specifically carbon, oxygen, and magnesium. The synthesis process involved two sequential steps: electroanodization of aluminum foil followed by a hydrothermal method using a mixture of glucose and magnesium chloride (MgCl2). The concentration of MgCl2 was systematically varied as the sole experimental variable across five levels-1 mM, 2 mM, 3 mM, 4 mM, and 5 mM-to investigate the impact of MgO formation on the samples' chemical and physical properties, and consequently, their CO2 capture efficiency. Thus, scanning electron microscopy analysis revealed the AAO substrate's porous structure, with pore diameters measuring 250 ± 30 nm. The growth of MgO on the AAO substrate resulted in spherical structures, whose diameter expanded from 15 nm ± 3 nm to 1000 nm ± 250 nm with increasing MgCl2 concentration from the minor to major concentrations explored, respectively. X-ray photoelectron spectroscopy (XPS) analysis indicated that carbon serves as a linking agent between AAO and MgO within the composite. Notably, the composite synthesized with a 4 mM MgCl2 concentration exhibited the highest CO2 capture efficiency, as determined by UV-Vis absorbance studies using a sodium carbonate solution as the CO2 source. This efficiency was quantified with a 'k' constant of 0.10531, significantly higher than those of other studied samples. The superior performance of the 4 mM MgCl2 sample in CO2 capture is likely due to the optimal density of MgO structures formed on the sample's surface, enhancing its adsorptive capabilities as suggested by the XPS results.

Biopolymeric Nanocomposites for Wastewater Remediation: An Overview on Recent Progress and Challenges

Essential for human development, water is increasingly polluted by diverse anthropogenic activities, containing contaminants like organic dyes, acids, antibiotics, inorganic salts, and heavy metals. Conventional methods fall short, prompting the exploration of advanced, cost-effective remediation. Recent research focuses on sustainable adsorption, with nano-modifications enhancing adsorbent efficacy against persistent waterborne pollutants. This review delves into recent advancements (2020-2023) in sustainable biopolymeric nanocomposites, spotlighting the applications of biopolymers like chitosan in wastewater remediation, particularly as adsorbents and filtration membranes along with their mechanism. The advantages and drawbacks of various biopolymers have also been discussed along with their modification in synthesizing biopolymeric nanocomposites by combining the benefits of biodegradable polymers and nanomaterials for enhanced physiochemical and mechanical properties for their application in wastewater treatment. The important functions of biopolymeric nanocomposites by adsorbing, removing, and selectively targeting contaminants, contributing to the purification and sustainable management of water resources, have also been elaborated on. Furthermore, it outlines the reusability and current challenges for the further exploration of biopolymers in this burgeoning field for environmental applications.