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Organic reactions generally involve a variety of catalysts and solvents, which may be inflammable, toxic, and/or corrosive. Consequently, most of these reactions highly influence the environment. However, recent science and technology applications shift towards eco-friendly and sustainable resources and processes. Nanocatalysis has recently become an emerging field of science owing to its high reactivity, productivity, and selectivity. Cellulose supported metal nanoparticles (NPs) have been broadly applied in catalysis toward the development of green and sustainable chemical transformation processes. Those catalysts can be easily recycled several times without losing their reactivity. Metal nanoparticles have recently attracted more attention as a result of their distinctive characteristics in comparison to their equivalent bulk metals. Those characteristics include a large surface-to-volume ratio, high porosity, and tunable structural morphology. Controlling the characteristics of nanoparticles particularly with respect to their structural morphology, particle size and dispersibility are essential because those will identify their catalytic activity. Recent developments in controlling dispersibility, particle size, and morphological shape of metal nanoparticles paved the way to optimize the nanoparticle geometry for improved catalytic activity. This review focuses on the fabrication and application of cellulose supported metal nanoparticles as promising catalysts for green modern organic synthesis and aims to present cellulose supported metal nanoparticles as a green, sustainable and renewable alternative to conventional catalysts for future industrial applications. The major groups of noble and transition metal nanoparticles are highlighted.

A solar photodegradation film for methylene blue (MB) removal has been fabricated using cellulose triacetate (CTA), graphene oxide (GO), and CaCO 3 . First, GO was prepared from graphite using the modified Hummers method, and its structure was confirmed by X-ray diffraction and Raman spectroscopy. CTA/GO film loaded with CaCO 3 (CTA/CaCO 3 /GO) was prepared by a simple casting method, and its structure was characterized using Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), and scanning electron microscopy (SEM)/ energy dispersive electron spectroscopy (EDX). Hydrophilicity was investigated using contact angle measurements, which confirmed the effectiveness of GO as a surface-modifying agent, transforming the CTA/CaCO 3 film into a more hydrophilic film. The solar photodegradation of MB dye by a CTA/CaCO 3 /GO film was investigated under varying pH, sorbent dosage, and contact time. The results showed that more than 90% of the MB dye was removed by CTA/CaCO 3 /GO under solar radiation after 2 h. The rate of solar photodegradation of MB dye by the CTA/CaCO 3 /GO film followed pseudo-second-order kinetics.

Cellulose has attracted much interest, particularly in medical applications such as advanced biosensing devices. Cellulose could provide biosensors with enhanced biocompatibility, biodegradability and non-toxicity, which could be useful for biosensors. Thus, they play a significant role in environmental monitoring, medical diagnostic tools, forensic science, and foodstuff processing safety applications. This review summarizes the recent developments in cellulose-based biosensors targeting the molecular design principles toward medical detection purposes. The recognition/detection mechanisms of cellulose-based biosensors demonstrate two major classes of measurable signal generation, including optical and electrochemical cellulosic biosensors. As a result of their simplicity, high sensitivity, and low cost, cellulose-based optical biosensors are particularly of great interest for including label-free and label-driven (fluorescent and colorimetric) biosensors. There have been numerous types of cellulose substrates employed in biosensors, including several cellulose derivatives, nano-cellulose, bacterial cellulose, paper, gauzes, and hydrogels. These kinds of cellulose-based biosensors were discussed according to their preparation procedures and detection principle. Cellulose and its derivatives with their distinctive chemical structure have demonstrated to be versatile materials, affording a high-quality platform for accomplishing the immobilization process of biologically active molecules into biosensors. Cellulose-based biosensors exhibit a variety of desirable characteristics, such as sensitivity, accuracy, convenience, quick response, and low-cost. For instance, cellulose paper-based biosensors are characterized as being low-cost and easy to operate, while nano-cellulose biosensors are characterized as having a good dispersion, high absorbance capacity, and large surface area. Cellulose and its derivatives have been promising materials in biosensors which could be employed to monitor various bio-molecules, such as urea, glucose, cell, amino acid, protein, lactate, hydroquinone, gene, and cholesterol. The future interest will focus on the design and construction of multifunctional, miniaturized, low-cost, environmentally friendly, and integrated biosensors. Thus, the production of cellulose-based biosensors is very important.

In this study, new amino heterocyclic cellulose derivatives were prepared. Dialdehyde cellulose was functionalized by Schiff base reaction with (E)-2-(4-(dimethylamino) benzylidene)-4-oxo-4-phenylbutanehydrazide, (E)-2-((1,3-diphenyl-1H-pyrazol-4-yl)-4-oxo-4-phenylbutane hydrazide, and thiophene-2-carbohydrazide. The prepared derivatives were characterized and confirmed by Fourier-transform infrared spectroscopy, scanning electron microscopy, energy-dispersive X-ray, and Thermo gravimetric analysis. Additionally, antimicrobial activity of all derivatives was assessed as well as antitumor activity. Results revealed that, all derivatives have potential antimicrobial activity against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus subtilis, Candida albicans, Cryptococcus neoformance, Aspergillus niger, A. fumigatus. Additionally, (E)-2-(4-(dimethylamino) benzylidene)-4-oxo-4-phenylbutanehydrazide and (E)-2-((1,3-diphenyl-1H-pyrazol-4-yl)-4-oxo-4-phenylbutanehydrazide cellulose compounds have good antitumor activities against Hep G2 and MCF7 cancerous cell lines without any effects on Wi38 normal cell line. Molecular dynamics study revealed that (E)-2-(4-(dimethylamino) benzylidene)-4-oxo-4-phenylbutanehydrazide and (E)-2-((1,3-diphenyl-1H-pyrazol-4-yl)-4-oxo-4-phenylbutanehydrazide cellulose derivatives have selectively target the ATP binding pocket residues. Identification of these ATP binding site residues and their crucial roles could provide the structure basis for understanding c-Kit kinase auto-inhibition

The chromium adsorption behavior from aqueous solution by the amphoteric Janus nitrogen-doped carbon quantum dots (AJ–N–CQDs) was investigated. The pseudo-first-order and the second-order adsorption kinetics models were employed to analyze the experimental data; the second-order adsorption kinetics model presented a better correlation to the experimental data, suggesting a chemisorptions process. The values obtained in the pseudo-first-order are still suitable for describing the Kinetics of Cr(VI) sorption. These values elucidate the surface processes involving chemisorption and physisorption in the adsorption of Cr(VI) by AJ–N–CQDs. The R 2 of the Boyd model gave a better fit to the adsorption data of AJ–N–CQDs (i.e., external diffusion), which means the surface processes involving external Cr(VI) adsorption by AJ–N–CQDs. The higher value of α may be due to the greater surface area of the AJ–N–CQDs for the immediate adsorption of Cr(VI) from the aqueous solution. AJ–N–CQDs have fluorescence spectra before and after Cr(VI) adsorption, indicating they are promising for chemical sensor applications.

The current rationale is exploring new eco-friendly UV- shielding films based on cellulose and thiazolidine. Cellulose was oxidized to dialdehyde cellulose (DAC) and tricarboxy cellulose (TCC) by periodate and TEMPO/periodate/hypochlorite, respectively. While E -3-amino-5-(phenyldiazenyl)-2-thioxothiazolidin-4-one (TH) was synthesized by coupling diazonium salt with the 5-methylene of 2-thioxo-4-thiazolidinone. DAC was then coupled with TH via Schiff base reaction and incorporated onto TCC with different ratios to get UV-shielding films. 1 HNMR, infrared spectroscopy (FTIR), and thermal gravimetric analysis (TGA) were used to investigate the chemical structure of the synthesized materials. In addition, the films' morphology, thermal, mechanical, and UV-shielding properties were investigated. The UV-shielding studies revealed that the film with 10% DAC-TH has 99.88, 99.99, and 96.19% UV-blocking (UVB), UV-absorbance (UVA), and Ultra-violet protection (UPF), respectively. Moreover, the prepared films demonstrated promising antimicrobial activity against Escherichia coli, S. aureus, P. aeruginosa, and Candida albicans. Finally, the prepared films showed no cytotoxic effects on normal human skin fibroblast's HFB-4 cell line.

In the present study, an integration of a hydrogeochemical investigation involving multivariate statistical analysis was conducted to identify the main processes governing spring water geochemistry in southeastern Tunisia. Springs geochemical composition is mainly controlled by water–rock interaction, dissolution of evaporite minerals, evaporation, and ion exchange reactions. The principal component analysis (PCA) confirms the dominance of the classical hydrochemical variables, originating from the natural weathering processes of sedimentary and evaporitic rocks in springs mineralization. Total dissolved solids (TDS), electrical conductivity (EC), and water quality parameters (sodium percentage, sodium adsorption ratio, magnesium hazard, permeability index, and Kelly’s ratio) confirm the irrigational suitability of the springs located in the Dahar plateau. Springs located in the wettest areas of the Dahar mountains were grouped separately in Gibb’s diagrams and in the PCA classification due to their low TDS values (< 866 mg/L). These springs show enrichment with stable isotopes (18O and 2H) composition confirming the current recharge by direct infiltration of rainwater. However, springs depleted in stable isotopes represent a probably longer residence time in the aquifer and exhibit mixing evaporation-dissolution processes. The d-excess values of springs located in the Gabes region show evidence of recharge water evaporation before infiltration. However higher values in the Dahar springs imply that rainwater is relatively less subjected to secondary evaporation during the recharge process. Results from this study demonstrate the benefits of using geochemical and isotopic data to confirm the possibility of spring water management in arid and semi-arid regions.

This study explores a sustainable court surface system using styrene acrylic emulsion (SAE) and styrene butadiene rubber (SBR) binders combined with waste rubber powder (WRP) to develop cushioning layers that reduce surface impact. A pure acrylic top coat, reinforced with rice husk (RH), was formulated to improve slip resistance, abrasion durability, and UV stability on the cushions. A comparative analysis evaluated how filler amount, WRP proportion, and binder type and content influence the physical, mechanical, thermal, and morphological properties of the cushions. Increasing SAE or SBR content in cushions by 8.21% enhanced their tensile strength by 30.28% and 32.77%, respectively, due to improved matrix cohesion. However, the microporous structure of WRP introduced voids that reduced tensile strength and elongation, particularly at high loadings or when binder content was low, reflecting a trade-off between mechanical performance and shock attenuation. CaCO 3 filler occupies voids within WRP, enhancing dimensional stability but disrupting polymer chain continuity and flexibility. This reduces free volume and limits chain mobility, both essential for elastic deformation. 15% RH-loaded topcoat reduced adhesion pull-off and elongation by 5.15% and 89.1%, respectively, while increasing tensile strength and abrasion resistance by 46% and 30.5%. These enhancements are attributed to the fibrous nature and filler interaction of RH within the acrylic matrix. The developed multilayer system is suited for indoor and outdoor multipurpose sports courts; such as those used for basketball and tennis where durability, shock absorption, and environmental sustainability are essential.

A series of novel pyrimidine and pyrimidopyrimidine analogs were synthesized in good yield from 6-amino-4-aryl-2-oxo-pyrimidine-5-carbonitrile ( 1a-d ). The synthesized compounds were characterized using various spectral studies, including FT-IR, 1 H NMR, 13 C NMR, mass spectrometry, and elemental analysis. Newly synthesized pyrimidopyrimidines and 2-(substituted-pyrazolyl)pyrimidine derivatives were assessed in vitro for their cytotoxic activities against three cancerous cell lines: colorectal carcinoma ( HCT-116 ), mammary gland breast cancer ( MCF-7 ), and hepatocellular carcinoma ( HEPG-2 ), as well as normal fibroblasts ( W138 ). The results indicated that compounds 3b , 10b , and 10c exhibited the highest cytotoxic activities, with IC 50 values very close to those of the reference drug (doxorubicin) across all studied cancerous cell lines, while also demonstrating good safety effects on the normal human lung fibroblast cell line. Furthermore, all the synthesized compounds were examined for their antimicrobial activity against two Gram-positive bacteria ( Staphylococcus aureus and Bacillus subtilis ), one Gram negative bacterium ( Escherichia coli ) and two fungal species ( Candida albicans and Aspergillus flavus ). The antimicrobial results of the synthesized compounds, when compared with the reference drugs ampicillin and clotrimazole, revealed that compounds 3a , 3b , 3d , 4a-d , 9c and 10b exhibited excellent antimicrobial activities. Moreover, membrane stabilization or anti-hemolytic activity was employed as a method to study the in vitro anti-inflammatory activity of the prepared heterocyclic compounds. Antioxidant activities were also assessed by measuring the percentage of free radical scavenging. Compounds 4b , 10c and 11a-c demonstrated strong anti-hemolytic and antioxidant effects, which can be attributed to their ability to protect red blood cells from hemolysis.

This work used a simple technique to prepare a novel cerium titanate nano-rods embedded in a cellulose-based hydrogel with high photo catalytic degradation activity. The composite hydrogel was prepared by embedding different amounts of cerium titanate nano-rods (Ce/Ti-NRs) into a crosslinked carboxymethyl cellulose/polyacrylamide polyelectrolyte complex (CMC/PAM) as a matrix material. The physico-chemical properties of the Ce/Ti-NRs, CMC/PAM, and cerium titanate nano-rods embedded in a cellulose-based hydrogel (Ce/Ti-NRs/CMC/PAM) were investigated by FT-IR, XRD, BET, TEM, SEM, and EDX techniques. The photo-degradation efficiency of the prepared composite hydrogel was investigated for their ability to simultaneously adsorb-degrade Congo red dye (CR) under different conditions such as the dosage of composite hydrogel, dye solution pH and temperature, degradation time, initial dye concentration, and agitation rate. Also, the kinetics of the CR degradation process was evaluated. The obtained data fits well using pseudo-first order kinetic model with R 2 equal to 0.911 and calculated equilibrium capacity value (22.44 mg/g) closer to the corresponding experimental values (23.193 mg/g) than those of pseudo-second order model with R 2 equal to 0.888 and calculated equilibrium capacity value (34.78 mg/g). The linear plot of the intra-particle model indicated that the simultaneously adsorb-degrade of CR dye by the composite hydrogel is likely to be complex. It involves both film diffusion (boundary layer diffusion) and intra-particle diffusion. The optimum developed composite hydrogel shows high simultaneously adsorb-degrade photo catalytic activity superior to other published results as it degraded 91.68% of CR dye only after 90 min.