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1.
Int J Biol Macromol ; 272(Pt 1): 132893, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38838883

RESUMO

Foodborne pathogens result in a great harm to human, which is an urgent problem to be addressed. Herein, a novel cellulose-based packaging films with excellent anti-bacterial properties under visible light were prepared. A porphyrin-based covalent organic polymer (Por-COPs) was constructed, then covalently grafted onto dialdehyde cellulose (DAC). The addition of Por-COPs enhanced the mechanical, hydrophobicity, and water resistance of the DAC-based composite films. DAC/Por-COP-2.5 film exhibited outstanding properties for the photodynamic inactivation of bacteria under visible light irradiation, delivering inactivation efficiencies of 99.90 % and 99.45 % towards Staphylococcus aureus and Escherichia coli within 20 min. The DAC/Por-COPs films efficiently generated •O2- and 1O2 under visible light, thereby causing oxidative stress to cell membranes for bacterial inactivation. The prepared composite film forms a protective barrier against bacterial contamination. Results guide the development of high performance and more sustainable packaging films for the food sector.


Assuntos
Celulose , Escherichia coli , Porfirinas , Staphylococcus aureus , Celulose/química , Celulose/análogos & derivados , Celulose/farmacologia , Porfirinas/química , Porfirinas/farmacologia , Escherichia coli/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos/farmacologia , Antibacterianos/química , Luz , Embalagem de Alimentos/métodos , Polímeros/química , Polímeros/farmacologia , Esterilização/métodos , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacologia
2.
Int J Mol Sci ; 25(12)2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38928182

RESUMO

Enantioseparation of nineteen liquid crystalline racemic mixtures obtained based on (R,S)-2-octanol was studied in reversed-phase mode on an amylose tris(3-chloro-5-methylphenylcarbamate) (ReproSil Chiral-MIG) and a cellulose tris(3,5-dichlorophenylcarbamate) (ReproSil Chiral-MIC). These polysaccharide-based chiral stationary phase (CSP) columns for High-Performance Liquid Chromatography (HPLC) were highly effective in recognizing isomers of minor structural differences. The mobile phase (MP), which consists of acetonitrile (ACN)/water (H2O) at different volume ratios, was used. The mobile phases were pumped at a flow rate of 0.3, 0.5, or 1 mL·min-1 with a column temperature of 25 °C, using a UV detector at 254 nm. The order of the elution was also determined. The chromatographic parameters, such as resolution (Rs), selectivity (α), and the number of theoretical plates, i.e., column efficiency (N), were determined. The polysaccharide-based CSP columns have unique advantages in separation technology, and this study has shown the potential usefulness of the CSP columns in separating liquid crystalline racemic mixtures belonging to the same homologous series.


Assuntos
Cromatografia de Fase Reversa , Cristais Líquidos , Polissacarídeos , Cristais Líquidos/química , Estereoisomerismo , Cromatografia de Fase Reversa/métodos , Cromatografia Líquida de Alta Pressão/métodos , Polissacarídeos/química , Amilose/química , Amilose/análogos & derivados , Celulose/química , Celulose/análogos & derivados , Fenilcarbamatos/química
3.
Int J Biol Macromol ; 273(Pt 1): 132998, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38866290

RESUMO

Paclitaxel, a diterpenoid isolated from the bark of Taxus wallichiana var. chinensis (Pilger) Florin, is currently showing significant therapeutic effects against a variety of cancers. Baccatin III (Bac) and 10-Deacetylbaccatin III (10-DAB) are in great demand as important precursors for the synthesis of paclitaxel. This work aims to develop a simple, rapid and highly selective, safe, and non-polluting molecularly imprinted material for 10-DAB and Bac enrichment. In this study, we innovatively prepared molecularly imprinted materials with nanocellulose aerogel microspheres and 2-vinylpyridine (2-VP) as a bifunctional monomer, and 10-DAB and Bac as bis-template molecules. In particular, functionalized nanocellulose dual-template molecularly imprinted aerogel microsphere (FNCAG-DMIM) were successfully synthesized by the bifunctional introduction of functional nanocellulose aerogel microsphere (FNCAG) modified with Polyethyleneimine (PEI) as a carrier and functional monomer, which provided a large number of recognition sites for bimodal molecules. FNCAG-DMIM showed high specificity for 10-DAB and Bac specific assays. Under the optimal experimental conditions, the adsorption capacities of FNCAG-DMIM for 10-DAB and Bac reached 52.27 mg g-1 and 53.81 mg g-1, respectively. In addition, it showed good reliability and practicality in the determination of real samples. The present study extends the research on the synthesis of natural functional monomers by molecularly imprinted materials and opens up new horizons for the targeted isolation of plant compounds by dual-template molecularly imprinted materials.


Assuntos
Celulose , Géis , Microesferas , Impressão Molecular , Celulose/química , Celulose/análogos & derivados , Géis/química , Impressão Molecular/métodos , Adsorção , Taxoides/química
4.
Int J Biol Macromol ; 273(Pt 2): 133119, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38880452

RESUMO

Ethyl cellulose (EC)-based composite sponges were developed for oil spillage treatment. The EC sponge surface was decorated with helical carbon nanotubes (HCNTs) and molybdenum disulfide (MoS2) (1 phr) using the inside-out sugar templating method. The inside surface of a sugar cube was coated with HCNTs and MoS2. After filling the sugar cube pores with EC and the subsequent sugar leaching, the decorating materials presented on the sponge surface. The EC/HCNT/MoS2 sponge had a high level of oil removal based on its adsorption capacity (41.68 g/g), cycled adsorption (∼75-79 %), separation flux efficiency (∼85-95 %), and efficiency in oil/water emulsion separation (92-94 %). The sponge maintained adsorption capacity in acidic, basic, and salty conditions, adsorbed oil under water, and functioned as an oil/water separator in a continuous pump-assisted system. The compressive stress and Young's modulus of the EC sponge increased following its decoration using HCNTs and MoS2. The composite sponge was robust based on cycled compression and was thermally stable up to ∼120 οC. Based on the eco-friendliness of EC, the low loading of HCNTs and MoS2, and sponge versatility, the developed EC/HCNT/MoS2 sponge should be good candidate for use in sustainable oil adsorption and separation applications.


Assuntos
Celulose , Dissulfetos , Molibdênio , Nanotubos de Carbono , Celulose/química , Celulose/análogos & derivados , Dissulfetos/química , Nanotubos de Carbono/química , Adsorção , Molibdênio/química , Água/química , Óleos/química , Purificação da Água/métodos
5.
Int J Biol Macromol ; 273(Pt 1): 132788, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38942669

RESUMO

Dye wastewater poses a serious threat to the environment and human health, necessitating sustainable degradation methods. In this study, Na-based Montmorillonite (MMT) was exfoliated using different ionic liquids ([C16MIM][Cl], [C16MIM][BF4], [C16MIM][PF6]), and silver nanoparticles (Ag NPs) were green-synthesized using hydroxypropyl cellulose (HPC). The HPC significantly enhanced the dispersion of MMT in the hydrogel. By introducing lauryl methacrylate (LMA), a hydrophobic associative network was constructed in PAM/LMA/HPC/MMT@ILs&Ag NPs hydrogel. This hydrogel demonstrated outstanding mechanical properties, with a stress of 833.21 kPa, strain of 3300 %, and toughness of 14.36 MJ/m3. It also exhibited excellent catalytic activity, with a rate constant of 0.83 min-1 for 4-nitrophenol degradation at 28 °C. The effects of temperature and catalyst concentration on the catalytic reaction were systematically investigated. This study presents a simple green synthesis approach for Ag NPs using HPC, achieving superior mechanical performance and stable MMT dispersion in aqueous solutions.


Assuntos
Bentonita , Celulose , Hidrogéis , Líquidos Iônicos , Nanopartículas Metálicas , Prata , Poluentes Químicos da Água , Celulose/química , Celulose/análogos & derivados , Líquidos Iônicos/química , Catálise , Bentonita/química , Hidrogéis/química , Poluentes Químicos da Água/química , Prata/química , Nanopartículas Metálicas/química , Ânions/química , Nitrofenóis/química , Química Verde , Purificação da Água/métodos
6.
Int J Biol Macromol ; 273(Pt 2): 132775, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38823732

RESUMO

A novel flame retardant containing Si, N, and S elements, ((2-(triethoxysilyl)ethyl)thio)ethan-1-amine hydrochloride (TETEA), was synthesized via a click reaction and characterized using nuclear magnetic resonance spectroscopy (NMR) and fourier transform infrared spectroscopy (FTIR). Subsequently, the flame-retardant cotton fabric was fabricated by sol-gel method. The results indicated that TETEA was successfully loaded on cotton fabric and formed a uniform protective layer on the surface of cotton fabric, exhibiting excellent flame retardancy. The flame-retardant cotton fabric achieved limiting oxygen index (LOI) of 28.3 % and passed vertical combustion test without after-flame or afterglow time at TETEA concentration of 500 g/L. Thermogravimetric analysis revealed that the residual carbon content of the flame-retardant cotton fabric was much higher than that of the control under air and N2 conditions. Besides, the flame-retardant cotton fabric was not ignited in cone calorimeter test with an external heat flux of 35 kW/m2. The peak heat release rate and the total heat release decreased from 133.4 kW/m2 to 25.8 kW/m2 and from 26.46 MJ/m2 to 17.96 MJ/m2, respectively. This phosphorus-free flame retardant offers a simplified synthesis process without adverse environmental impacts, opening up a new avenue for the development environmentally friendly flame retardants compared to traditional alternatives.


Assuntos
Celulose , Fibra de Algodão , Retardadores de Chama , Retardadores de Chama/síntese química , Retardadores de Chama/análise , Fibra de Algodão/análise , Celulose/química , Celulose/análogos & derivados , Nitrogênio/química , Silício/química , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria , Substâncias Macromoleculares/química , Substâncias Macromoleculares/síntese química
7.
Int J Biol Macromol ; 273(Pt 2): 133212, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38897502

RESUMO

Cellulases from GH9 family show endo-, exo- or processive endocellulase activity, but the reason behind the variation is unclear. A GH9 recombinant endoglucanase, AtGH9C-CBM3A-CBM3B from Acetivibrio thermocellus was structurally characterized for conformation, binding and dynamics assessment. Modeled AtGH9C-CBM3A-CBM3B depicted (α/α)6-barrel structure with Asp98, Asp101 and Glu489 acting as catalytic triad. CD results revealed 25.2 % α-helix, 18.4 % ß-sheet and rest 56.4 % of random coils, corroborating with predictions from PSIPRED and SOPMA. MD simulation of AtGH9C-CBM3A-CBM3B bound cellotetraose showed structural stability and global compactness with lowered RMSD values (1.5 nm) as compared with only AtGH9C-CBM3A-CBM3B (1.8 nm) for 200 ns. Higher fluctuation in RMSF values in far-positioned CBM3B pointed to its redundancy in substrate binding. Docking studies showed maximum binding with cellotetraose (ΔG = -5.05 kcal/mol), with reduced affinity towards ligands with degree of polymerization (DP) lower (DP < 4) or higher than 4 (DP > 4). Processivity index displayed the enzyme to be processive with loop 3 (342-379 aa) possibly blocking the non-reducing end of cellulose chain, resulting in cellotetraose release. SAXS analysis of AtGH9C-CBM3A-CBM3B at 5 mg/mL displayed monodispersed state with fist-and-elbow shape in solution. Negative zeta potential of -24 mV at 5 mg/mL indicated stability and free from aggregation.


Assuntos
Celulase , Simulação de Dinâmica Molecular , Ligação Proteica , Proteínas Recombinantes , Celulase/química , Celulase/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/genética , Especificidade por Substrato , Tetroses/metabolismo , Tetroses/química , Sequência de Aminoácidos , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Celulose/análogos & derivados
8.
Biomacromolecules ; 25(7): 4046-4062, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38913613

RESUMO

Ethylcellulose (EC) is a crucial cellulose derivative with widespread applications, particularly in the pharmaceutical industry, where precise property adjustments through chemical modification are imperative. The degree of substitution (DS) and the localization of substituents along the cellulose chains are pivotal factors in this process. However, the impact of the substituent location within the repeating unit of EC remains unexplored. To address this gap, we conducted molecular dynamics simulations on amorphous EC, comparing randomly and uniformly substituted ethyl groups in the repeating units. This comprehensive study of pairwise interactions revealed significant differences in intramolecular and intermolecular hydrogen-bonding capabilities, depending on whether the hydroxyl groups were substituted at C2, C3, or C6. While our simulations demonstrated that substituent localization in the repeating unit influenced the density, number of hydrogen bonds, and conformations, the DS emerged as the dominant determinant. This insight led us to propose and validate a hypothesis: a straightforward linear function using the properties of uniform models and molar fractions can predict the properties of randomly substituted EC with a given DS. This innovative approach is anticipated to contribute to the selection of cellulose derivatives with desirable properties for the pharmaceutical industry and new applications in other fields.


Assuntos
Celulose , Ligação de Hidrogênio , Simulação de Dinâmica Molecular , Celulose/química , Celulose/análogos & derivados
9.
Biosens Bioelectron ; 261: 116498, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38878697

RESUMO

The World Anti-Doping Agency (WADA) has prohibited the use of clenbuterol (CLN) because it induces anabolic muscle growth while potentially causing adverse effects such as palpitations, anxiety, and muscle tremors. Thus, it is vital to assess meat quality because, athletes might have positive test for CLN even after consuming very low quantity of CLN contaminated meat. Numerous materials applied for CLN monitoring faced potential challenges like sluggish ion transport, non-uniform ion/molecule movement, and inadequate electrode surface binding. To overcome these shortcomings, herein we engineered bimetallic zeolitic imidazole framework (BM-ZIF) derived N-doped porous carbon embedded Co nanoparticles (CN-CoNPs), dispersed on conductive cellulose acetate-polyaniline (CP) electrospun nanofibers for sensitive electrochemical monitoring of CLN. Interestingly, the smartly designed CN-CoNPs wrapped CP (CN-CoNPs-CP) electrospun nanofibers offers rapid diffusion of CLN molecules to the sensing interface through amine and imine groups of CP, thus minimizing the inhomogeneous ion transportation and inadequate electrode surface binding. Additionally, to synchronize experiments, machine learning (ML) algorithms were applied to optimize, predict, and validate voltametric current responses. The ML-trained sensor demonstrated high selectivity, even amidst interfering substances, with notable sensitivity (4.7527 µA/µM/cm2), a broad linear range (0.002-8 µM), and a low limit of detection (1.14 nM). Furthermore, the electrode exhibited robust stability, retaining 98.07% of its initial current over a 12-h period. This ML-powered sensing approach was successfully employed to evaluate meat quality in terms of CLN level. To the best of our knowledge, this is the first study of using ML powered system for electrochemical sensing of CLN.


Assuntos
Técnicas Biossensoriais , Celulose , Clembuterol , Cobalto , Aprendizado de Máquina , Nanofibras , Clembuterol/análise , Nanofibras/química , Técnicas Biossensoriais/métodos , Celulose/química , Celulose/análogos & derivados , Cobalto/química , Animais , Carne/análise , Nanopartículas Metálicas/química , Compostos de Anilina/química , Técnicas Eletroquímicas/métodos , Contaminação de Alimentos/análise , Análise de Alimentos/métodos , Análise de Alimentos/instrumentação , Limite de Detecção , Carbono/química
10.
Mol Pharm ; 21(7): 3375-3382, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38885189

RESUMO

Recent work has shown that an amorphous drug-polymer salt can be highly stable against crystallization under hot and humid storage conditions (e.g., 40 °C/75% RH) and provide fast release and that these advantages depend on the degree of salt formation. Here, we investigate the salt formation between the basic drug lumefantrine (LMF) and several acidic polymers: poly(acrylic acid) (PAA), hypromellose phthalate (HPMCP), hypromellose acetate succinate (HPMCAS), cellulose acetate phthalate (CAP), Eudragit L100, and Eudragit L100-55. Salt formation was performed by "slurry synthesis" where dry components were mixed at room temperature in the presence of a small quantity of an organic solvent, which was subsequently removed. This method achieved more complete salt formation than the conventional methods of hot-melt extrusion and rotary evaporation. The acidic group density of a polymer was determined by nonaqueous titration in the same solvent used for slurry synthesis; the degree of LMF protonation was determined by X-ray photoelectron spectroscopy. The polymers studied show very different abilities to protonate LMF when compared at a common drug loading, following the order PAA > (HPMCP ∼ CAP ∼ L100 ∼ L100-55) > HPMCAS, but the difference largely disappears when the degree of protonation is plotted against the concentration of the available acidic groups for reaction. This indicates that the extent of salt formation is mainly controlled by the acidic group density and is less sensitive to the polymer architecture. Our results are relevant for selecting the optimal polymer to control the degree of ionization in amorphous solid dispersions.


Assuntos
Polímeros , Polímeros/química , Metilcelulose/química , Metilcelulose/análogos & derivados , Cristalização/métodos , Celulose/química , Celulose/análogos & derivados , Resinas Acrílicas/química , Sais/química , Derivados da Hipromelose/química , Solubilidade
11.
J Nanobiotechnology ; 22(1): 337, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38886712

RESUMO

BACKGROUND: Molybdenum disulfide (MoS2) has excellent physical and chemical properties. Further, chiral MoS2 (CMS) exhibits excellent chiroptical and enantioselective effects, and the enantioselective properties of CMS have been studied for the treatment of neurodegenerative diseases. Intriguingly, left- and right-handed materials have different effects on promoting the differentiation of neural stem cells into neurons. However, the effect of the enantioselectivity of chiral materials on peripheral nerve regeneration remains unclear. METHODS: In this study, CMS@bacterial cellulose (BC) scaffolds were fabricated using a hydrothermal approach. The CMS@BC films synthesized with L-2-amino-3-phenyl-1-propanol was defined as L-CMS. The CMS@BC films synthesized with D-2-amino-3-phenyl-1-propanol was defined as D-CMS. The biocompatibility of CMS@BC scaffolds and their effect on Schwann cells (SCs) were validated by cellular experiments. In addition, these scaffolds were implanted in rat sciatic nerve defect sites for three months. RESULTS: These chiral scaffolds displayed high hydrophilicity, good mechanical properties, and low cytotoxicity. Further, we found that the L-CMS scaffolds were superior to the D-CMS scaffolds in promoting SCs proliferation. After three months, the scaffolds showed good biocompatibility in vivo, and the nerve conducting velocities of the L-CMS and D-CMS scaffolds were 51.2 m/s and 26.8 m/s, respectively. The L-CMS scaffolds showed a better regenerative effect than the D-CMS scaffolds. Similarly, the sciatic nerve function index and effects on the motor and electrophysiological functions were higher for the L-CMS scaffolds than the D-CMS scaffolds. Finally, the axon diameter and myelin sheath thickness of the regenerated nerves were improved in the L-CMS group. CONCLUSION: We found that the CMS@BC can promote peripheral nerve regeneration, and in general, the L-CMS group exhibited superior repair performance. Overall, the findings of this study reveal that CMS@BC can be used as a chiral nanomaterial nerve scaffold for peripheral nerve repair.


Assuntos
Celulose , Dissulfetos , Molibdênio , Regeneração Nervosa , Células de Schwann , Alicerces Teciduais , Regeneração Nervosa/efeitos dos fármacos , Animais , Ratos , Alicerces Teciduais/química , Dissulfetos/química , Dissulfetos/farmacologia , Células de Schwann/efeitos dos fármacos , Molibdênio/química , Molibdênio/farmacologia , Celulose/química , Celulose/farmacologia , Celulose/análogos & derivados , Ratos Sprague-Dawley , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Nervo Isquiático/efeitos dos fármacos , Nervo Isquiático/fisiologia , Proliferação de Células/efeitos dos fármacos , Engenharia Tecidual/métodos , Masculino , Traumatismos dos Nervos Periféricos , Estereoisomerismo
12.
Int J Biol Macromol ; 271(Pt 2): 132680, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38806087

RESUMO

Microbeads of biodegradable polyhydroxybutyrate (PHB) offer environmental benefits and economic competitiveness. The aim of this study was to encapsulate a water-soluble bioactive compound, niacinamide (NIA), in a pH-responsive natural matrix composed of PHB and cellulose acetate phthalate (CAP) by double emulsification (W1/O/W2) to improve the encapsulation efficiency (%EE) and loading capacity (%LC). PHB was produced in-house by Escherichia coli JM109 pUC19-23119phaCABA-04 without the inducing agent isopropyl ß-D-1-thiogalactopyranoside (IPTG). The influences of PHB and polyvinyl alcohol (PVA) concentrations, stirring rate, PHB/CAP ratio and initial NIA concentration on the properties of NIA-loaded pH-responsive microbeads were studied. The NIA-loaded pH-responsive PHB/CAP microbeads exhibited a spherical core-shell structure. The average size of the NIA-loaded pH-responsive microbeads was 1243.3 ± 11.5 µm. The EE and LC were 33.3 ± 0.5 % and 28.5 ± 0.4 %, respectively. The release profiles of NIA showed pH-responsive properties, as 94.2 ± 3.5 % of NIA was released at pH 5.5, whereas 99.3 ± 2.4 % of NIA was released at pH 7.0. The NIA-loaded pH-responsive PHB/CAP microbeads were stable for >90 days at 4 °C under darkness, with NIA remaining at 73.65 ± 1.86 %. A cytotoxicity assay in PSVK1 cells confirmed that the NIA-loaded pH-responsive PHB/CAP microbeads were nontoxic at concentrations lower than 31.3 µg/mL, in accordance with ISO 10993-5.


Assuntos
Celulose , Emulsões , Hidroxibutiratos , Microesferas , Niacinamida , Celulose/química , Celulose/análogos & derivados , Concentração de Íons de Hidrogênio , Hidroxibutiratos/química , Niacinamida/química , Água/química , Poliésteres/química , Solubilidade , Liberação Controlada de Fármacos , Humanos , Proibitinas , Poli-Hidroxibutiratos
13.
Int J Biol Macromol ; 270(Pt 1): 132176, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38750845

RESUMO

Cancer is a fatal disease, and unfortunately, the anticancer drugs harm normal cells. Plant's extracts are the golden key to solving this issue. In this research, fig latex - from Ficus carica- was encapsulated using cellulose acetate (CA) and poly (ethylene oxide) (PEO) polymers via electrospinning method (Fig@CA/PEO). Fig@CA/PEO nanofiber scaffold was characterized by thermogravimetric analysis (TGA), Fourier-transform infrared spectroscopy (FT-IR), and scanning electron microscopy (SEM). The average fiber diameter was decreased with an increase in latex concentration from 715 nm to 583 nm. FT-IR spectroscopy indicated the presence of fig latex in Fig@CA/PEO nanofibers. Compared to 5-fluorouracil, Fig@CA/PEO nanofiber scaffold considered safe towards normal cells (WI-38). Moreover, the nanofiber scaffold was efficient against colon cancer cells (Caco) and liver cancer cells (HepG2) as it demonstrated IC50 values for cells by 23.97 µg/mL and 23.96 µg/mL, respectively. Besides, the nanofiber scaffold revealed mechanistic variations in apoptotic oncogenes; described by the upregulation of BCL2 and P21, combined by downregulation of p53 and TNF. Moreover, the nanofiber scaffold showed antioxidant activity counting 33.4, 36 and 41 % of DPPH scavenging as the fig latex concentration increased. The results demonstrate that the Fig@CA/PEO nanofiber scaffold is a promising substitute to traditional chemotherapy.


Assuntos
Antineoplásicos , Antioxidantes , Celulose , Ficus , Látex , Nanofibras , Polietilenoglicóis , Nanofibras/química , Celulose/química , Celulose/análogos & derivados , Celulose/farmacologia , Humanos , Ficus/química , Polietilenoglicóis/química , Antioxidantes/farmacologia , Antioxidantes/química , Látex/química , Látex/farmacologia , Antineoplásicos/farmacologia , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Células Hep G2 , Espectroscopia de Infravermelho com Transformada de Fourier , Linhagem Celular Tumoral
14.
J Dent ; 146: 105038, 2024 07.
Artigo em Inglês | MEDLINE | ID: mdl-38714242

RESUMO

OBJECTIVES: This laboratory study assessed the performance of a novel fluoride dentifrice containing micro-fibrillated cellulose (MFC) and entrapped silica. METHODS: Removal of extrinsic stains was assessed using the pellicle cleaning ratio (PCR) method, and radioactive dentin abrasivity (RDA) was measured, to calculate a cleaning efficiency index (CEI). Fluoride efficacy was evaluated using widely used remineralization and fluoride uptake methods. The test product (Protegera™) was compared to common dentifrices (Crest - Cavity Protection™ and ProHealth™, Sensodyne Pronamel™, Arm & Hammer™ Advanced Whitening, Crest ProHealth™, and Colgate Optic White™). RESULTS: The PCR for the MFC dentifrice (141) was comparable to three known marketed stain-removing dentifrices (Arm & Hammer™ Advanced Whitening, Crest ProHealth™, and Colgate Optic White™) but it had a significantly lower RDA (88 ± 6) than 5 other products. This gave it the highest CEI of the tested products (2.0). In a 10-day pH cycling study, the fluoride efficacy of the MFC product was comparable to Sensodyne Pronamel and Crest Cavity Protection. The MFC dentifrice was superior for promoting fluoride uptake into incipient enamel lesions compared to the USP reference dentifrice. CONCLUSION: The MFC dentifrice has low abrasion, but despite this, it is highly effective in removing stained pellicle. It also is an efficacious fluoride source when compared to relevant commercially available fluoride dentifrices with high dentin abrasivity. CLINICAL SIGNIFICANCE: The addition of micro-fibrillated cellulose to a fluoride dentifrice gives a low abrasive product that can effectively remove external stains, and serve as an effective fluoride source. This combination of benefits seems well suited to enamel protection and caries prevention.


Assuntos
Celulose , Dentifrícios , Dentina , Abrasão Dentária , Descoloração de Dente , Remineralização Dentária , Dentifrícios/uso terapêutico , Dentifrícios/química , Descoloração de Dente/prevenção & controle , Celulose/análogos & derivados , Humanos , Abrasão Dentária/prevenção & controle , Dentina/efeitos dos fármacos , Remineralização Dentária/métodos , Cariostáticos/uso terapêutico , Cariostáticos/química , Película Dentária/efeitos dos fármacos , Fluoretos/uso terapêutico , Dióxido de Silício/química , Teste de Materiais , Esmalte Dentário/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Fosfatos/uso terapêutico , Cremes Dentais/química , Cremes Dentais/uso terapêutico
15.
Int J Biol Macromol ; 271(Pt 2): 132374, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38754669

RESUMO

The controlled delivery of the desired bioactive molecules is required to achieve the maximum therapeutic effects with minimum side effects. Biopolymer-based hydrogels are ideal platforms for delivering the desired molecules owing to their superior biocompatibility, biodegradability, and low-immune response. However, the prolonged delivery of the drugs through biopolymer-based hydrogels is restricted due to their weak mechanical stability. We developed mechanically tough and biocompatible hydrogels to address these limitations using carboxymethyl chitosan, sodium alginate, and nanocellulose for sustained drug delivery. The hydrogels were cross-linked through calcium ions to enhance their mechanical strength. Nanocellulose-added hydrogels exhibited improved mechanical strength (Young's modulus; 23.36 â†’ 30.7 kPa, Toughness; 1.39 â†’ 5.65 MJm-3) than pure hydrogels. The composite hydrogels demonstrated increased recovery potential (66.9 â†’ 84.5 %) due to the rapid reformation of damaged polymeric networks. The hydrogels were stable in an aqueous medium and demonstrated reduced swelling potential. The hydrogels have no adverse effects on embryonic murine fibroblast (3 T3), showing their biocompatibility. No bacterial growth was observed in hydrogels-treated groups, indicating their antibacterial characteristics. The sustained drug released was observed from nanocellulose-assisted hydrogel scaffolds compared to the pure polymer hydrogel scaffold. Thus, hydrogels have potential and could be used as a sustained drug carrier.


Assuntos
Celulose , Quitosana , Hidrogéis , Celulose/química , Celulose/análogos & derivados , Hidrogéis/química , Camundongos , Animais , Quitosana/química , Quitosana/análogos & derivados , Sistemas de Liberação de Medicamentos , Alginatos/química , Materiais Biocompatíveis/química , Liberação Controlada de Fármacos , Preparações de Ação Retardada , Portadores de Fármacos/química , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/administração & dosagem , Nanopartículas/química
16.
Int J Biol Macromol ; 271(Pt 1): 132435, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38759856

RESUMO

The increasing electromagnetic pollution is urgently needed as an electromagnetic interference shielding protection device for wearable devices. Two-dimensional transition metal carbides and nitrides (MXene), due to their interesting layered structure and high electrical conductivity, are ideal candidates for constructing efficient conductive networks in electromagnetic interference shielding materials. In this work, lightweight and robust cellulose/MXene/polyurethane composite aerogels were prepared by mixing cellulose nanofiber (CNF) suspensions with MXene, followed by freeze-drying and coating with polyurethane. In this process, CNF effectively assembled MXene nanosheets into a conductive network by enhancing the interactions between MXene nanosheets. The prepared aerogel exhibited the shielding effectiveness of 48.59 dB in the X-band and an electrical conductivity of 0.34 S·cm-1. Meanwhile, the composite aerogel also possessed excellent thermal insulation, infrared stealth, mechanical and hydrophobic properties, and can be used as a wearable protective device to protect the human body from injuries in different scenarios while providing electromagnetic interference shielding protection.


Assuntos
Celulose , Poliuretanos , Dispositivos Eletrônicos Vestíveis , Celulose/química , Celulose/análogos & derivados , Poliuretanos/química , Géis/química , Humanos , Condutividade Elétrica , Nanocompostos/química , Nanofibras/química
17.
Int J Biol Macromol ; 271(Pt 2): 132591, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38788873

RESUMO

This study focused on synthesis of innovative hydrogels with electric field response from modified pineapple peel cellulose and hericium erinaceus chitosan and gelatin based on Schiff base reaction. A series of hydrogels were prepared by oxidized hydroxyethyl cellulose, gelatin and chitosan at different deacetylation degree via mild Schiff base reaction. Subsequently experiments towards the characterization of oxidized hydroxyethyl cellulose/gelatin/chitosan (OHGCS) hydrogel polymers were carried out by FTIR/XRD/XPS, swelling performances and electric response properties. The prepared hydrogels exhibited stable and reversible bending behaviors under repeated on-off switching of electric fields, affected by ionic strength, electric voltage and pH changes. The swelling ratio of OHGCS hydrogels was found reduced as deacetylation degree increasing and reached the maximum ratio âˆ¼ 2250 % for OHGCS-1. In vitro drug releasing study showed the both curcumin loading capacity and release amount of Cur-OHGCS hydrogels arrived about 90 % during 6 h. Antioxidation assessments showed that the curcumin-loaded hydrogels had good antioxidation activities, in which, 10 mg Cur-OHGCS-1 hydrogel could reach to the maximum of about 90 % DPPH scavenging ratio. These results indicate the OHGCS hydrogels have potentials in sensor and drug delivery system.


Assuntos
Ananas , Antioxidantes , Celulose , Quitosana , Curcumina , Gelatina , Hidrogéis , Quitosana/química , Gelatina/química , Curcumina/química , Hidrogéis/química , Ananas/química , Celulose/química , Celulose/análogos & derivados , Antioxidantes/química , Antioxidantes/farmacologia , Liberação Controlada de Fármacos , Basidiomycota/química , Portadores de Fármacos/química , Concentração de Íons de Hidrogênio , Eletricidade , Celulose Oxidada/química , Sistemas de Liberação de Medicamentos
18.
Int J Biol Macromol ; 271(Pt 1): 132576, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38788883

RESUMO

With increasing concern for the environment, the demand for carbon dioxide separation, a key contributor to global warming, has escalated. Therefore, this paper focuses on carbon dioxide separation by creating an hydroxyethyl cellulose (HEC)(C2H6O2)x*(C6H7O2(OH)3)n/silver tetra fluoroborate (AgBF4)/aluminum nitrate (Al(NO3)3) composite film, demonstrating excellent separation performance with a permeance of 1.0 GPU and a selectivity of 100. Silver ions enhance the solubility of carbon dioxide, aiding in its separation, and we determined the optimal aluminum composition to stabilize the silver ions. To analyze this, we examined the cross-sections using SEM, confirming a selective layer of 1.7 µm for carbon dioxide separation. Furthermore, TGA, FT-IR, and NMR analyses were conducted to investigate the interaction between the polymer and additives. This revealed that the increased polymer chain due to the interaction between Ag and HEC, along with stabilized Ag facilitated by the addition of Al, maximized the interaction with carbon dioxide via the empty s-orbital. Additionally, SEM-EDX, UV-vis, XRD, XPS analyses were employed to elucidate the movement of ions within the membrane. These results provide insights into the performance of membranes based on cellulose polymer and offer valuable insights for future applications in gas separation technologies.


Assuntos
Dióxido de Carbono , Celulose , Celulose/química , Celulose/análogos & derivados , Dióxido de Carbono/química , Gases/química , Prata/química , Química Verde/métodos
19.
Int J Biol Macromol ; 270(Pt 1): 132221, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38729499

RESUMO

Cellulose acetate (CA) is a non-toxic, renewable, and biodegradable polymeric material that can be effectively electrospuned into bacterial filtration efficient nanofiber membrane for face mask application. However, its fragile and non-antibacterial nature influenced its scalability. In this context, natural antibacterial gum rosin (GR) additive can be explored. Therefore, the present study aimed to produce a CA/GR composite nanofibers membrane for the finest bacterial filtration, excellent antibacterial moiety, and improved tensile properties for facemask application. Hence, in this work, we have studied the effect of GR concentrations (0-15 g) on the needleless electrospinning behavior and fibers' morphology through rheology, electrical conductivity, and SEM analysis. These analyses revealed that GR significantly affects the fibers' spinning behavior, morphology, and diameter of the produced fibers. Later, ATR-FTIR spectroscopy mapped the functional changes in the produced nanofibers that affirmed the integration of GR with CA polymer. This modification resulted in a 3-fold rise in tensile strength and an 11-fold decline in elongation% in 15 g CA/GR composite nanofibers membrane than the control sample. Furthermore, it has shown 98.79 ± 0.10% bacterial filtration efficiency and âˆ¼ 93 % reduction in Staphylococcus Aureus and Klebsiella Pneumoniae bacterial growth, elucidating a high-efficiency level for potential facemask application.


Assuntos
Antibacterianos , Bactérias , Celulose , Máscaras , Nanofibras , Resinas Vegetais , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Condutividade Elétrica , Filtração/métodos , Filtração/normas , Máscaras/microbiologia , Máscaras/normas , Nanofibras/química , Nanofibras/microbiologia , Nanofibras/ultraestrutura , Resinas Vegetais/química , Reologia , Celulose/análogos & derivados , Celulose/química , Celulose/farmacologia
20.
Environ Res ; 252(Pt 3): 119068, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38705452

RESUMO

Cellulose acetate membranes exhibit a potential to be applied in hemodialysis. However, their performance is limited by membrane fouling and a lack of antibacterial properties. In this research, copper oxide (I) nanoparticles were fabricated in situ into a cellulose acetate matrix in the presence of polyvinylpyrrolidone (pore-forming agent) and sulfobetaine (stabilising agent) to reduce the leakage of copper ions from nano-enhanced membranes. The influence of nanoparticles on the membrane structure and their antibacterial and antifouling properties were investigated. The results showed that incorporating Cu2O NPs imparted significant antibacterial properties against Staphylococcus aureus and fouling resistance under physiological conditions. The Cu2O NPs-modified membrane could pave the way for potential dialysis applications.


Assuntos
Antibacterianos , Incrustação Biológica , Celulose , Cobre , Membranas Artificiais , Staphylococcus aureus , Celulose/análogos & derivados , Celulose/química , Celulose/farmacologia , Cobre/química , Antibacterianos/farmacologia , Antibacterianos/química , Staphylococcus aureus/efeitos dos fármacos , Incrustação Biológica/prevenção & controle , Nanopartículas/química , Nanopartículas Metálicas/química , Povidona/química , Povidona/análogos & derivados
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