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In this study, novel Cu-complexes of heterocyclic cellulose which were synthesized via the reaction of carboxymethyl cellulose (CMC) from bagasse pulp with NH 2 NH 2 to give hydrazide cellulose which easily reacted with CS 2 to form salt and then cyclized in the presence of HCl to afford cellulose oxadiazole, or with hydrazine hydrate to give cellulose triazole. Furthermore, the cellulose oxadiazole and triazole moieties acting as chelating agents with metal ion Cu (II), and all synthesized compounds were examined for their spectral analysis to show the adsorption of Cu (II) on the surface of cellulose through intramolecular hydrogen bonding. Results illustrated that cellulose oxadiazole and Cu- cellulose oxadiazole exhibited antimicrobial activities more than triazole and Cu- cellulose triazole. Furthermore, anticancer results showed that both cellulose oxadiazole and triazole exhibited activity higher than Cu-cellulose oxadiazole and Cu-cellulose triazole, where the cellulose triazole showed the highest activity (IC50 = 58.7 μg/μL). Additionally, the docking simulation of the synthesized cellulose complexes with different proteins such as PDBID:3t88, PDBID:4ynt, PDBID:1tgh, PDBID:2wje, and PDBID:4hdq and shortage bond length to confirm the experimental results. Optimization of metal complexes utilized the DFT/B3LYP/LANL2DZ basis set to confirm the stability of these metals theoretically and their physical descriptors and FMO analysis., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Improving electron transfer rate of Co species and inhibiting aggregation of metal-organic frameworks (MOFs) particles are essential prerequisites for activating advanced oxidation process in wastewater treatment field. Here, we exploit Cu species with variable valence states to accelerate electron transfer of Co species and then to boost the unsatisfactory degradation efficiency for refractory pharmaceuticals via in-situ growth of copper and cobalt species on l-lysine functionalized carboxylated cellulose nanofibers. Utilizing the synergistic interplay of Co sites and deliberately exposed Cu 0 /Cu 1+ atoms, the subtly designed catalyst exhibited a surprising degradation efficiency (~100 %) toward tetracycline hydrochloride within 10 min (corresponding to a catalytic capacity of 267.71 mg/g) without adjusting temperature and pH. Meanwhile, the catalyst displays good recyclability, well tolerance for coexisting ions and excellent antibacterial performance derived from the intrinsic antibacterial property of Cu-MOF. This research provided a novel strategy to construct MOFs-cellulose materials toward degrading various stubborn antibiotic pollutants., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The quality of wine can be affected by excess Cu 2+ due to the occurrence of oxidation reactions or precipitation. Therefore, it is essential to use simple and effective testing methods to ensure the Cu 2+ content in wine. In this work, we designed and synthesized a rhodamine polymer fluorescent probe (PEG-R). The water solubility of PEG-R was improved by the introduction of polyethylene glycol, which improved the performance and broadened its application in the food field. The PEG-R was characterized by high sensitivity, selectivity and fast response to Cu 2+ and was able to complete the response process within 30 s, with approximately 29-fold fluorescence enhancement of the probe after exposure to Cu 2+ , the limit of detection (LOD) was 1.295 × 10 -6 M. The probe can be used for the determination of Cu 2+ in living cells, zebrafish, white wine and food products, and it was made into practical gels and test strips., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

There is a high demand for high performance, effective and eco-friendly corrosion inhibitors for industrial applications. Therefore, novel benign high performance corrosion inhibitors based on biopolymer were synthesized in-situ using different cellulosic materials and niacin. Characterization of the cellulose nano-composite was carried out by Fourier transform infrared (FTIR), thermal gravimetric analysis (TGA), dynamic light scattering (DLS), scanning electron microscopy (SEM) and energy dispersive X-ray (EDX). The anticorrosive performance of cellulose composites for copper in 3.5% NaCl solutions were evaluated using polarization and electrochemical impedance spectroscopy (EIS) techniques. Surface morphology of uninhibited and inhibited composites was studied using SEM and EDX. Potentiodynamic polarization measurements confirmed that cellulose based inhibitors act as a mixed type inhibitor. The inhibition efficiency of ethyl cellulose-niacin composite (NEC) was 94.7% outperforms those of microcrystalline cellulose-niacin composite (NMCC) and carboxymethyl cellulose-niacin composite (NCMC) which were 33.2 and 83.4%, respectively, as green corrosion inhibitors for Copper in 3.5% NaCl solutions. The data extracted from EIS were fitted through an equivalent circuit to model the corrosion inhibition., (Copyright © 2020 Elsevier B.V. All rights reserved.)

In this work, silanized and aminated lignin (SAL) was synthesized in one step and its adsorption of Congo red and Cu(II) ions in aqueous solution was explored. Lignin was subjected to amine-silanization with (3-aminopropyl) triethoxysilane (APTES). Structural characterization substantiated successful amine-silanzation of lignin and formation of multi-layer APTES intermolecular crosslinked structure. The prepared SAL (nitrogen content = 6.1%) exhibited enhanced molecular weight, thermal stability, and water- and organic solvent-resistance properties. Additionally, the present of the porous structure of particle surface and an increase in the specific surface area and zeta potential promoted the accessibility of contaminants to the effective adsorption sites of SAL. Adsorption experiments showed that both Congo red and Cu(II) ion could be completely removed at original pH value, and their adsorption involved electrostatic attraction and complexation, respectively. The adsorption isotherms and kinetics were well described by the Langmuir and pseudo-second-order equations, respectively. The results showed that SAL is a promising adsorbent for the treatment of effluents., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Cellulose nanocrystals (CNCs), having a high specific surface area and versatile surface chemistry, provide considerable potential to interact by various mechanisms with enzymes for nano-immobilization purposes. However, engineering chemically safe CNCs, suitable for edible administrations, presents a significant challenge. A reliable carboxylate form of H-CNCs was formed using H 2 O 2 oxidation of softwood pulp under mild thermal conditions. Negatively charged carboxyl groups (∼0.9 mmol g -1 ) played a key role in lysozyme immobilization via electrostatic interactions and covalent linkages, as evidenced by Fourier transform infrared and 13 C cross-polarization magic angle spinning nuclear magnetic resonance spectroscopies. Adsorption isotherms showed a high loading capacity of H-CNCs (∼240 mg g -1 ), and fitting the data to the Langmuir model confirmed monolayer coverage of lysozyme on their surface. Using a non-toxic coupling agent, 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride, lysozyme-conjugated H-CNCs were developed with an immobilization yield of ∼65% and relative catalytic activity of ∼60%, similar to lysozyme adsorption on H-CNCs. These H-CNC-lysozyme nanohybrids, rationally processed via safe and green strategies, are specifically exploitable as catalytically active emulsifiers in food and pharmaceutical sectors.

Cellulose-based materials are widely used in the biomedical field. However, the lack of antibacterial activities of cellulose fibers inevitably causes bacterial infection damages. In this study, Schiff base was first introduced to endow the cellulose fibers good antibacterial property and copper ions were complexed with Schiff base to form a complex. The prepared complex greatly enhanced the antibacterial properties of the cellulose fibers. FT-IR, XRD, UV-vis and SEM-EDS results proved the successful synthesis of Schiff base and its copper (II) complex. The antibacterial tests indicated that the width of the inhibition zone of the as-prepared cellulose-based Schiff base-Cu (II) complex against E. coli and S. aureus increased by 472 % and 823 %, respectively, in comparison to the Schiff base ligand. This significant increase could be attributed to the incorporation of the copper ions (II). This Schiff base-Cu (II) complex containing cellulose-based antibacterial materials are expected to be widely used for biomedical application., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Cellulose nanocrystal (CNC) and ZnO/CuO nanostructure were successfully synthesized by acid hydrolysis and sol-chemical methods, respectively. For the first time, CNC was used as a host polymer for synthesis of CNC/ZnO/CuO through In-situ solution casting technique. Morphological and structural of CNC, ZnO/CuO and hybrid CNC/ZnO/CuO were investigated by TEM, SEM-EDX, FT-IR, XRD and XPS analyses. The analysis revealed that, poly-dispersed, smooth and rod like CNC with an average length of ∼ 85.4 nm, average diameter of ∼13.9 nm and surface charge of 0.01 mmol/gm. As well, irregular shapes as hexagonal, spherical and cluster or star like of ZnO/CuO were formed. EDX and XRD spectra exhibited highly purified CNC/ZnO/CuO and pointed to cellulose II crystallite form with a monoclinic structure. The results demonstrated that, 91.3 % and 99.7 % dye degradation was achieved after 40 min of irradiation due to ZnO/CuO and CNC/ZnO/CuO treatment. Moreover, the inhibition zones formed due to 100 ppm ZnO/CuO were duplicated after integrating CNC (from 7.7:10.3 mm to 14.3:20.3 mm). The hybrid nanostructure exhibit larvicidal activity against Anopheles stephensi better than CNC and ZnO/CuO nanostructures., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

The study focuses on degradation efficiency of non-radical activation and radical activation systems of persulfate (PS) to degrade imidacloprid (IMI) by using sodium persulfate (SPS) as PS source. Copper oxide (CuO)-SPS and CuO/biochar (BC)-SPS were selected as PS non-radical activation systems, and pyrite (PyR)-SPS was selected as PS radical activation system. The degradation by CuO-SPS, CuO/BC-SPS and PyR-SPS systems was investigated from acidic to basic conditions (pH 3.0-11.0). Highest degradation by CuO-SPS and CuO/BC-SPS systems was achieved over pH 11.0. In contrast, highest degradation by PyR-SPS system was achieved over pH 3.0, however, PyR-SPS system was also found effective up to pH 9.0. It was found that degradation was more efficient in PS radical activation system, indicating that IMI could be oxidized by radicals rather than by activated PS. Electron paramagnetic resonance (EPR) analysis was carried out to investigate the generation of sulfate (SO 4 - ) and hydroxyl (OH) radicals, which indicated the presence of SO 4 - and OH in CuO-SPS, CuO/BC and PyR-SPS systems. However, free radical quenching analysis indicated that radicals were main reactive oxygen species for degradation. The lower degradation in PS non-radical activation systems was probably resulted from radicals existed as minor reactive oxygen species. The findings indicated that non-radical oxidation systems showed low reality for degradation and good degradation could be achieved by radical oxidation system. The degradation was also carried out in real waters to investigate the potential applicability of applied systems, which supported PyR-SPS system for effective degradation., (Copyright © 2019 Elsevier Inc. All rights reserved.)

We successfully absorbed the copper ion (Cu 2+ ) and cadmium ion (Cd 2+ ) from alkaline aqueous solutions using the prepared chitosan-tannin (CTS/TA) functional paper as absorbent materials. The kinetics of the adsorption, the adsorption isotherms, and the influence of the solution flow rate and pH were investigated detailly. The adsorption data were described well by Langmuir isotherms, with maximum copper (Cu 2+ ) and cadmium (Cd 2+ ) adsorption capacities of 684.93 and 813.01 mg/m 2 , respectively. The experimental results also showed that the adsorption of these heavy metals was selective in the order of Cu 2+  > Cd 2+ , as Cu 2+ competed with Cd 2+ for bonding sites at solution concentrations greater than or equal to 200 mg/L. The results of this study illustrated that the chitosan-tannin functional paper materials mainly followed a complexation-adsorption model, and the best adsorption capacity was achieved at pH = 9. The desorption of heavy ions from this adsorbent and its reusability of functional paper was also involved. Therefore, this novel, environment-friendly functional paper can surely act as an effective adsorbent for the removal and recovery of heavy metals in alkaline aqueous solutions., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

In this work regenerated cellulose was prepared by phosphoric acid as a primarily step in preparation of biodegradable foam. Copper nanoparticles (Cu-NPs) were embedded onto the cellulosic suspensions followed by freeze drying process. The scanning electron microscopy (SEM) revealed the presence of individual chunky regenerated cellulose fibers in the dimensions of micro that enhanced tendency to aggregate during drying. X-ray diffraction (XRD) demonstrated that, the treatment of cellulose with concentrated phosphoric acid led to defibrated cellulose with lower crystallinity index than original cellulose fibers. The study provided insights about the influence of the Cu-NPs on the structure, thermal stability and the electrical contributions of the considered cellulose-based foam. The electrical and dielectric properties were studied by means of the broadband dielectric spectroscopy. The dielectric spectra were dominated by an anomalous behavior of the permittivity as illustrated versus frequency of the investigated samples. The real part of conductivity follows the universal power law at higher frequencies. The foam loaded Cu-NPs exhibit biodegradability and highly efficient antimicrobial activity against Staphylococcus aureus, Pseudomonas aeruginosa, and Candida albicans., (Copyright © 2019 Elsevier B.V. All rights reserved.)

In this study, we report a smart and green strategy to synthesize copper sulfide nanoparticles (CuS-NPs) for clinically translatable cancer treatment. For the first time, the preparation of CuS-NPs was developed by taking advantage of the copper-amine complex as the copper source and sodium sulfide as the sulfide source, in which the quaternized chitosan (QCS) was used as a biotemplate and stabilizing agent. The obtained QCS/CuS-NPs composites (CuS@QCS-NPs) were spherical and stable with an average diameter of 5.6 nm, and showed strong NIR absorbance for photothermal conversion. Moreover, in vitro and in vivo cancer theranostic capability of CuS@QCS-NPs without any biomodification was evaluated. The result reveals that after intratumoral (i.t.) injection of CuS@QCS-NPs with NIR laser irradiation (808 nm, 1.5 W/cm 2 , 5 min), the 4T1 mammary tumor growth could be effectively suppressed comparing with the other control groups, and there was no obvious lethal toxicity to liver function, kidney function, and vital organs. Such QCS-stabilized CuS-NPs may provide an alternative for clinical application of CuS-based photothermal therapy., (Copyright © 2018. Published by Elsevier B.V.)

A two-photon fluorescent probe for Cu 2+ and S 2- has been strategically prepared with naphthalimide derivative platform (NPE) covalently grafted onto the surface of magnetic core-shell Fe 3 O 4 @SiO 2 nanoparticles. The probe (NPE-Fe 3 O 4 @SiO 2 ) exhibits selective response to Cu 2+ with enhanced fluorescence and efficient separation of Cu 2+ with external magnetic field. The consequent product NPE-Fe 3 O 4 @SiO 2 -Cu of NPE-Fe 3 O 4 @SiO 2 and Cu 2+ can work as an excellent sensor for S 2- by removing Cu 2+ from the complex with fluorescence decreased, recovering the fluorescence of the probe. Therefore, the constituted Off-On-Off type fluorescence monitoring system means the probe is resumable. Moreover, the probe has been used to quantitatively detect Cu 2+ and S 2- with low detection limits, which are 0.28 μM and 0.12 μM, respectively. Furthermore, the probe shows low cytotoxicity and excellent membrane permeability, which has been successfully applied for monitoring Cu 2+ and S 2- in living cells and imaging Cu 2+ in deep-tissue with two-photon excited fluorescence., (Copyright © 2018. Published by Elsevier B.V.)

Iron-copper bimetal supported on mesoporous γ-Al 2 O 3 with different Fe/Cu ratios was prepared via a modified evaporation-induced self-assembly method and employed to degrade 4-chlorophenol (4-CP) in a Fenton-like process. The X-ray photoelectron spectroscopy, X-ray diffraction spectrum and UV-vis diffuse reflectance spectroscopy results confirmed the co-doping of Fe 2+ /Fe 3+ and Cu + /Cu 2+ into the lattice of γ-Al 2 O 3 through the bonds of AlOFe and AlOCu. With the iron and copper co-doped in γ-Al 2 O 3 , three-fold oxygen vacancies (V 0 ) could be achieved compared with that of non-metal catalysts, which was favorable for the reduction of iron and copper species. The 1Fe3Cu-γ-Al 2 O 3 with a Fe/Cu mass ratio of 1:3 exhibited the highest activity on Fenton-like degradation of 4-CP due to the synergistic effects of Fe and Cu by facilitating the electron transfer in the recycles of Cu + /Cu 2+ and Fe 2+ /Fe 3+ based on the results of X-ray photoelectron spectroscopy, cyclic voltammetry and electro paramagnetic resonance analysis. The utilization efficiency of H 2 O 2 was as high as 86.0% when 4-CP almost disappeared (i.e., 99.7 percent of 0.78 mM 4-CP) at 240 min and pH 7.0, additionally, their dechlorination and TOC removal efficiencies were 92.0% and 81.6%, respectively. The catalyst also displayed a good performance after 5th cycles. Furthermore, a possible mechanism for activation of OH on the catalyst surface was also proposed., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Quaternized carboxymethyl chitosan/organic rectorite (QCMC/OREC) nanocomposites were rapidly prepared by intercalating QCMC into the layer of OREC under microwave irradiation. And then copper-chelate QCMC/OREC (QCMC/OREC-Cu) nanocomposites were obtained by mixing QCMC/OREC with CuSO4 solution. XRD and TEM results indicated that QCMC/OREC nanocomposites were obtained and QCMC was dispersed in the interlayer of OREC. Besides, FT-IR results revealed that the hydrogen bonds and electrostatic interaction in QCMC/OREC-Cu were both stronger than those in QCMC/OREC because of introducing the Cu(2+). The thermogravimetric analysis showed that the thermal stability of QCMC/OREC-Cu nanocomposites was higher than QCMC and QCMC/OREC. Algae inhibition assay revealed that QCMC/OREC-Cu nanocomposites had stronger antifouling activity than original QCMC and QCMC/OREC. This work provides important basis for developing novel antifouling materials., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

To obtain environmentally friendly antifouling agent, an effort was made to intercalate carboxymethyl chitosan into the interlayer of organic montmorillonite to prepare carboxymethyl chitosan/organic montmorillonite nanocomposites and their copper complexes. In comparison, carboxymethyl chitosan-copper complexes were also obtained. Their structures were characterized by X-ray diffaraction, transmittance electron microscopy and Fourier transform infrared, and their thermal behavior and antimicrobial activity were discussed. The results revealed that the interlayer distance of carboxymethyl chitosan/organic montmorillonite nanocomposites enlarged with the increasing mass ratio of carboxymethyl chitosan to organic montmorillonite, when the mass ratio was at 20:1, the layer spacing of carboxymethyl chitosan/organic montmorillonite nanocomposites reached the maximum of 3.68 nm. As compared to other samples, carboxymethyl chitosan/organic montmorillonite-copper nanocomposites showed much higher thermal stability and inhibitory activity against Escherichia coli, the lowest minimum inhibition concentration was only 0.0003125% (w/v). The study provides a new method to find novel antifouling agent., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Preparation of a new water-soluble, cellulose derivative via a supramolecular route is presented. In a one-step procedure, carboxymethyl cellulose (CMC) was reacted with the Cu(BF4)2 complex of 4'-chloro[2,2':6',2″]terpyridine to generate the desired CMC-Cu(II)-terpyridine derivative. This polymeric salt was characterized by elemental analysis, ultraviolet-visible spectroscopy (UV-visible), Fourier transform infrared (FTIR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), rheological properties measurements, thermogravimetric analysis (TGA), dynamic mechanical thermal analysis (DMTA), and tensile strength properties testing. In addition, antimicrobial properties were demonstrated against Gram-positive bacteria (Staphylococcus aureus and Streptococcus thermophilus), Gram-negative bacteria (Escherichia coli), and yeast (Saccharomyces cervisiae). The minimum inhibitory concentration of the prepared metallo-terpyridine CMC derivative against the studied microorganisms ranged from 6 to 8 mg/L to achieve ≥90% of microbial growth inhibition., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

In this paper, cupric oxides was found to effectively oxidize levulinic acid (LA) and lead to the decarboxylation of levulinic acid to 2-butanone. The effects of cupric oxide dosage, reaction time and initial pH value were investigated in batch experiments and a plausible mechanism was proposed. The results showed that LA decarboxylation over cupric oxides at around 300 °C under acidic conditions produced the highest yield of butanone (67.5%). In order to elucidate the catalytic activity of cupric oxides, XRD, AFM, XPS and H(2)-TPR techniques was applied to examine their molecular surfaces and their effects on the reaction process.