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1.
Carbohydr Polym ; 259: 117749, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33673979

RESUMO

The increasing world-wide demand for food has prompted the development of efficient and environmentally friendly pesticide formulations. In this article, we have prepared CMC-g-PRSG carrier based on two compounds from natural materials carboxymethyl cellulose (CMC) and rosin (RS). The model pesticide avermectin (AVM) was encapsulated through hydrophobic interaction, and self-assembled to form nanopesticide AVM@CMC-g-PRSG with an average particle size of 167 nm. The prepared nanopesticide displays enhanced dispersibility and stability of AVM in water, and can effectively adhere to the leaves to prevent loss. The release rate of AVM encapsulated in the nanocarrier can be controlled by adjusting pH, and AVM half-life under ultraviolet radiation shows a 3-fold increase allowing control of pests for prolonged periods of time in practical applications. Biological safety tests showed that AVM@CMC-g-PRSG effectively reduces the toxicity of AVM to aquatic animals. Therefore, the cheap and degradable carrier CMC-g-PRSG can improve the effect of hydrophobic pesticides.


Assuntos
Carboximetilcelulose Sódica/química , Portadores de Fármacos/química , Resinas Vegetais/química , Animais , Liberação Controlada de Fármacos , Meia-Vida , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Ivermectina/análogos & derivados , Ivermectina/química , Ivermectina/metabolismo , Ivermectina/farmacologia , Larva/efeitos dos fármacos , Nanopartículas/química , Tamanho da Partícula , Controle de Pragas/métodos , Praguicidas/química , Praguicidas/metabolismo , Praguicidas/farmacologia , Raios Ultravioleta , Peixe-Zebra/crescimento & desenvolvimento , Peixe-Zebra/fisiologia
2.
Food Chem ; 352: 129319, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-33691215

RESUMO

Emulsions based on licorice essential oil (LEO) were prepared under different homogenization conditions (ultra-homogenization (U1) or U1 together with sonication (U2)). The obtained emulsions were incorporated into the carboxymethyl cellulose (CMC) film. The results showed that U2 caused significant changes in the size and the surface charge of the emulsions. Remarkable differences in the microstructure were observed between the U1 and the U2 emulsion-based films as revealed by SEM and AFM. Both emulsions reduced the rigidity and increased the flexibility of the films. The film made from the CMC alone had a water vapor permeability (WVP) of 2.66 × 10-9 g m-1 s-1 Pa-1, while the CMC film made from U2 emulsion had a WVP of 1.87 × 10-9 g m-1 s-1 Pa-1. Also, the film containing 0.0125% U1-LEO exhibited antibacterial activity on gram-positive bacteria only while the film containing 0.0125% U2-LEO demonstrated antibacterial activity on both gram-positive and gram-negative bacteria.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Glycyrrhiza/química , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Sonicação , Carboximetilcelulose Sódica/química , Emulsões , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Permeabilidade , Vapor
3.
Food Chem ; 349: 129208, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33578247

RESUMO

The edible films composed ofcarboxymethyl cellulose (CMC), glycerol, mucilage from Chinese yam (DOM)and ZnO nanoparticles (ZnO-NPs), were prepared by a casting method. To evaluate the applicability for food packaging, prepared films were characterised morphological, physical, rheological, mechanical and barrier properties, performed FT-IR, thermal analysis, and finally investigated the antibacterial activity and acute oral toxicity of films. The surface of films presented irregular arrangement with nanoparticles combined in the networks, suggesting the best "CMC to DOM weight ratio" of approximately 1:1 could provide a smooth surface. The films with 2.0 g ZnO-NPs presented antibacterial effects against both Gram-positive (S. aureus) and Gram-negative (E. coli) bacteria. With the increase of DOM, the antibacterial rate dropped at 400 and 450 µL/mL. The film-forming solutions with higher ZnO-NPs content display shear-thinning properties and liquid-like behaviour. The edible films have a great potential to be used in application in food packaging.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Carboximetilcelulose Sódica/química , Dioscorea/química , Filmes Comestíveis , Glicerol/química , Óxido de Zinco/química , Escherichia coli/efeitos dos fármacos , Nanocompostos/química , Nanopartículas/química , Staphylococcus aureus/efeitos dos fármacos
4.
Carbohydr Polym ; 255: 117395, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33436223

RESUMO

Yogurt drinks can potentially be an appropriate medium for delivering probiotics to consumers. This study investigated the influences of the water-soluble fraction of bitter almond gum (SBAG) and its conjugate with sodium caseinate (SBAG-SC) compared to carboxymethylcellulose (CMC) and inulin, respectively, on the physical stability of casein micelles and the viability of the probiotic culture (Lactobacillus acidophilus La-5) in probiotic yogurt drink during cold storage. The addition of SBAG-SC conjugate to the drinks successfully prevented phase separation for a longer time than CMC. CMC-based drinks exhibited a strong shear-thinning response. Adding SBAG helped keep Lactobacillus acidophilus La-5 viable above the recommended level for probiotic products. However, the SBAG showed relatively less prebiotic property than inulin. This study demonstrated that SBAG-SC conjugate has a high potential for stabilizing applications in yogurt and yogurt products.


Assuntos
Suplementos Nutricionais/análise , Gomas Vegetais/química , Prebióticos/análise , Probióticos/análise , Prunus dulcis/química , Iogurte/análise , Carboximetilcelulose Sódica/química , Caseínas/química , Armazenamento de Alimentos/métodos , Glicoconjugados/química , Humanos , Inulina/química , Lactobacillus acidophilus/fisiologia , Extração Líquido-Líquido/métodos , Micelas , Iogurte/microbiologia
5.
Carbohydr Polym ; 256: 117506, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33483028

RESUMO

Direct deposition of the negatively charged polyelectrolyte, carboxymethyl cellulose (CMC), into a bacterial cellulose (BC) matrix was used as a simple route to fabricate a re-swellable and biocompatible cellulose-based hydrogel. As a result of this non-destructive approach, the physical and mechanical property of the original BC were well-preserved within the resulting BC/CMC hydrogel. As a BC/CMC-based colorimetric pH sensor, it exhibited a rapid response with an easy color differentiation between each pH by the naked eye, and wide linear range of pH 4.0-9.0 with good linearity. For the detection of glucose in sweat, the BC/CMC-based colorimetric glucose sensor provided a low limit of detection (25 µM) with a wide linear detection range (0.0-0.5 mM) and high accuracy. These BC/CMC based sensors could potentially be applied as non-invasive semi-quantitative sensors for on-skin health monitoring.


Assuntos
Técnicas Biossensoriais , Celulose/química , Colorimetria/métodos , Gluconacetobacter xylinus/química , Glucose/análise , Suor/química , Carboximetilcelulose Sódica/química , Cor , Humanos , Hidrogéis , Concentração de Íons de Hidrogênio , Limite de Detecção , Eletricidade Estática , Água/química , Molhabilidade
6.
Molecules ; 26(3)2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-33499342

RESUMO

Cartilage has a limited inherent healing capacity after injury, due to a lack of direct blood supply and low cell density. Tissue engineering in conjunction with biomaterials holds promise for generating cartilage substitutes that withstand stress in joints. A major challenge of tissue substitution is creating a functional framework to support cartilage tissue formation. Polyvinyl alcohol (PVA) was crosslinked with glutaraldehyde (GA), by varying the mole ratios of GA/PVA in the presence of different amounts of plant-derived carboxymethyl cellulose (CMC). Porous scaffolds were created by the freeze-drying technique. The goal of this study was to investigate how CMC incorporation and crosslinking density might affect scaffold pore formation, swelling behaviors, mechanical properties, and potential use for engineered cartilage. The peak at 1599 cm-1 of the C=O group in ATR-FTIR indicates the incorporation of CMC into the scaffold. The glass transition temperature (Tg) and Young's modulus were lower in the PVA/CMC scaffold, as compared to the PVA control scaffold. The addition of CMC modulates the pore architecture and increases the swelling ratio of scaffolds. The toxicity of the scaffolds and cell attachment were tested. The results suggest that PVA/CMC scaffolding material can be tailored in terms of its physical and swelling properties to potentially support cartilage formation.


Assuntos
Carboximetilcelulose Sódica/química , Cartilagem Articular/citologia , Cartilagem Articular/fisiologia , Álcool de Polivinil/química , Tecidos Suporte/química , Materiais Biocompatíveis/química , Varredura Diferencial de Calorimetria , Cartilagem Articular/lesões , Adesão Celular/fisiologia , Sobrevivência Celular , Células Cultivadas , Condrócitos/citologia , Condrócitos/fisiologia , Reagentes para Ligações Cruzadas , Módulo de Elasticidade , Humanos , Hidrogéis , Teste de Materiais , Microscopia Eletrônica de Varredura , Porosidade , Regeneração/fisiologia , Espectroscopia de Infravermelho com Transformada de Fourier , Engenharia Tecidual/métodos , Cicatrização/fisiologia
7.
Food Chem ; 340: 127950, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-32896780

RESUMO

This study aimed to prepare anthocyanin-rich microcapsules by spray and freeze-drying complex coacervated double emulsion using gelatin-acacia gum (GE-AG) and chitosan-carboxymethylcellulose (CS-CMC) and to investigate their properties and in vitro release kinetics. Microencapsulation efficiency (MEE) of the microcapsules varied from 84.9% to 94.7%. CS-CMS microcapsules showed significantly higher MEEs than those of GE-AG microcapsules. A significant higher MEE and lower moisture content and hygroscopicity was observed in spray-dried double emulsion (SDE) microcapsules. Freeze-dried double emulsion (FDE) microcapsules possessed higher total anthocyanin and total phenolic contents. The best fit for release kinetics was achieved using first-order and Higuchi models for SDE and FDE microcapsules, respectively. Diffusion-controlled release in the simulated gastric fluid was found for SDE microcapsules, while erosion-controlled release in simulated gastric and intestinal fluids predominated for FDE microcapsules. These findings suggest that the microcapsules can be applied for loading anthocyanins as a nutraceutical with controllable release requirement.


Assuntos
Antocianinas/química , Cápsulas , Carboximetilcelulose Sódica/química , Quitosana/química , Liberação Controlada de Fármacos , Emulsões , Liofilização , Goma Arábica/química , Cinética , Fenóis/química
8.
Chemosphere ; 262: 127733, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32763574

RESUMO

In this study, carboxymethyl cellulose (CMC) was employed to stabilize zero-valent iron nanoparticles (CMC-nFe0) to improve their dispersity and antioxidation for enhanced hexavalent chromium (Cr(VI)) removal. Scanning electron microscope (SEM) observation revealed that the nFe0 agglomerated in clusters, while the CMC-nFe0 connected as chains and presented higher dispersity. Therefore, compared with 54% of the nFe0, the Cr(VI) removal rate of the CMC-nFe0 increased by 0.8 time, reaching 97%. Besides, the nFe0 precipitated in 1 d and was obviously oxidized within 7 d under anoxic condition, leading to a rapid decease of Cr(VI) removal efficiency from 54% to 3% in 56 d. In contrast, the CMC-nFe0 showed no obvious subsidence and oxidized phenomenon within 14 d, which retained a relatively high Cr(VI) removal efficiency of 63% in 56 d, contributing to effective blockage of dissolved oxygen infiltrating from solution to nFe0 particles in presence of CMC. After reaction, the valence state distribution of Cr between solution and material surface indicated that Cr(VI) reduction was dominant comparing to physical adsorption to particles in the remediation process conducted by CMC-nFe0. In addition, lower initial pH and higher iron dosage facilitated Cr(VI) removal. Those results indicated that the dispersive and antioxidative characteristics of CMC-nFe0 were significantly superior to those of nFe0, and CMC stabilization thereafter can be a promising method to promote Cr(VI) elimination by nFe0.


Assuntos
Antioxidantes/química , Cromo/isolamento & purificação , Ferro/química , Poluentes Químicos da Água/isolamento & purificação , Adsorção , Carboximetilcelulose Sódica/química , Cromo/química , Concentração de Íons de Hidrogênio , Nanopartículas Metálicas/química , Microscopia Eletrônica de Varredura , Oxirredução , Oxigênio , Poluentes Químicos da Água/química
9.
ACS Appl Mater Interfaces ; 13(1): 1353-1366, 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33351585

RESUMO

Stimulus-responsive hydrogels, such as conductive hydrogels and thermoresponsive hydrogels, have been explored extensively and are considered promising candidates for smart materials such as wearable devices and artificial muscles. However, most of the existing studies on stimulus-responsive hydrogels have mainly focused on their single stimulus-responsive property and have not explored multistimulus-responsive or multifunction properties. Although some works involved multifunctionality, the prepared hydrogels were incompatible. In this work, a multistimulus-responsive and multifunctional hydrogel system (carboxymethyl cellulose/poly acrylic-acrylamide) with good elasticity, superior flexibility, and stable conductivity was prepared. The prepared hydrogel not only showed excellent human motion detection and physiological signal response but also possessed the ability to respond to environmental temperature changes. By integrating a conductive hydrogel with a thermoresponsive poly(N-isopropylacrylamide) (PNIPAM) hydrogel to form a bilayer hydrogel, the prepared bilayer also functioned as two kinds of actuators owing to the different degrees of swelling and shrinking under different thermal stimuli. Furthermore, the different thermochromic properties of each layer in the bilayer hydrogel endowed the hydrogel with a thermoresponsive "smart" feature, the ability to display and conceal information. Therefore, the prepared hydrogel system has excellent prospects as a smart material in different applications, such as ionic skin, smart info-window, and soft robotics.


Assuntos
Carboximetilcelulose Sódica/química , Hidrogéis/química , Monitorização Fisiológica/instrumentação , Dispositivos Eletrônicos Vestíveis , Resinas Acrílicas/química , Alumínio/química , Elasticidade , Condutividade Elétrica , Humanos , Movimento , Temperatura , Termômetros
10.
Carbohydr Polym ; 252: 117156, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33183607

RESUMO

A new natural formulation composed of CMC and various contents of CNC immobilized AgNPs (CNC@AgNPs) was developed for paper coating. The mechanical strength, water vapor and air barrier properties, and antibacterial activities of CMC/CNC@AgNPs coated paper improved with the increasing content of CNC@AgNPs. CMC/CNC@AgNPs7 % coated paper exhibited 1.26 times increase in tensile strength, 45.4 % decrease in WVP, 93.3 % reduction in air permeability as well as the best antibacterial activities against E.coli and S.aureus compared with uncoated paper. Moreover, the cumulative release rate of AgNPs from coated paper significantly reduced due to the immobilization effect of CNC on AgNPs. Furthermore, CMC/CNC@AgNPs coated paper was used to package strawberries under ambient conditions. The results showed that coated paper could maintain better strawberries quality compared with unpackaged strawberries and extend the shelf-life of strawberries to 7 days. Therefore, the prepared CMC/CNC@AgNPs coated paper will have a great application prospect in the food packaging.


Assuntos
Antibacterianos/farmacologia , Carboximetilcelulose Sódica/química , Embalagem de Alimentos , Nanopartículas Metálicas/química , Nanocompostos/química , Prata/farmacologia , Escherichia coli/efeitos dos fármacos , Permeabilidade , Staphylococcus aureus/efeitos dos fármacos , Vapor , Resistência à Tração
11.
Molecules ; 26(1)2020 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-33375128

RESUMO

The demand for more ecological, highly engineered hydrogel beads is driven by a multitude of applications such as enzyme immobilization, tissue engineering and superabsorbent materials. Despite great interest in hydrogel fabrication and utilization, the interaction of hydrogels with water is not fully understood. In this work, NMR relaxometry experiments were performed to study bead-water interactions, by probing the changes in bead morphology and surface energy resulting from the incorporation of carboxymethyl cellulose (CMC) into a cellulose matrix. The results show that CMC improves the swelling capacity of the beads, from 1.99 to 17.49, for pure cellulose beads and beads prepared with 30% CMC, respectively. Changes in water mobility and interaction energy were evaluated by NMR relaxometry. Our findings indicate a 2-fold effect arising from the CMC incorporation: bead/water interactions were enhanced by the addition of CMC, with minor additions having a greater effect on the surface energy parameter. At the same time, bead swelling was recorded, leading to a reduction in surface-bound water, enhancing water mobility inside the hydrogels. These findings suggest that topochemical engineering by adjusting the carboxymethyl cellulose content allows the tuning of water mobility and porosity in hybrid beads and potentially opens up new areas of application for this biomaterial.


Assuntos
Carboximetilcelulose Sódica/química , Celulose/química , Engenharia Química , Espectroscopia de Ressonância Magnética , Microesferas , Algoritmos , Engenharia Química/métodos , Portadores de Fármacos/química , Hidrogéis/química , Espectroscopia de Ressonância Magnética/métodos , Modelos Químicos
12.
Chemosphere ; 261: 128123, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33113646

RESUMO

A pot experiment was carried out to evaluate the efficiency of six types of non-stabilised and Na-carboxymethylcellulose (CMC)-stabilised iron oxide nanoparticles (α-FeOOH, α-Fe2O3, and Fe3O4) on the immobilisation of cobalt (Co) in a soil spiked with different concentrations of it (5, 25, 65, 125, 185 mg kg-1). Amendments were added to soil samples at the rate of 0.5%, and the samples incubated for 60-days. The addition of amendments significantly decreased the concentrations of DTPA-Co and MgCl2-Co, compared with the unamended control. The highest decrease in concentration of DTPA-Co and MgCl2-Co was obtained by the application of CMC-stabilised Fe3O4 (MC) when the concentration of soil total Co was low (5 and 25 mg kg-1) and by the use of CMC-stabilised α-FeOOH (GC) when the concentration of soil total Co was high (65, 125, and 185 mg kg-1), as compared to the control. CMC-stabilised iron oxide nanoparticles were more effective than non-stabilised nanoparticles in the immobilisation of Co. To investigate the effectiveness of iron oxide amendments on the chemical species of Co in the soil spiked with 65 mg kg-1 of this metal, sequential extraction was performed. The concentration of EXCH (exchangeable) and CARB (carbonate) bound fractions decreased significantly after treatment by different amendments. In particular, GC reduced the concentration of EXCH and CARB bound fractions by 20.87, and 17.52%, respectively, compared with the control. Also amendments significantly increased the concentration of FeMn-OX (Fe-Mn oxides), and OM (organic matter) bound, and RES (residual) fractions.


Assuntos
Carboximetilcelulose Sódica/química , Cobalto/análise , Recuperação e Remediação Ambiental/métodos , Compostos Férricos/química , Nanopartículas/química , Poluentes do Solo/análise , Solo/química
13.
Chemosphere ; 255: 127052, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32679636

RESUMO

In this study, polypyrrole/carboxymethyl cellulose nanocomposite particles (PPy/CMC NPs) were synthesized and applied for removal of reactive red 56 (RR56)and reactive blue 160 (RB160) as highly toxic dyes. The amount of CMC was found significantly effective on the surface adsorption efficiency. Different optimization methods including the genetic programming, response surface methodology, and artificial neural network (ANN) were used to optimize the effect of different parameters including pH, adsorption time, initial dye concentration and adsorbent dose. The maximum adsorption of RR56 and RB160 were found under the following optimum conditions: pH of 4 and 5, adsorption time of 55 min and 52 min for RR56 and RB160, respectively, initial dye concentration of 100 mg/L and adsorbent dose of 0.09 g for both dyes. were obtained for RR56 and RB160, respectively. Also, the results indicated that ANN method could predict the experimental adsorption data with higher accuracy than other methods. The analysis of ANN results indicated that the adsorbent dose is the main factor in RR56 removal, followed by time, pH and initial concentration, respectively. However, initial concentration mostly determines the RB160 removal process. The isotherm data for both dyes followed the Langmuir isotherm model with a maximum adsorption capacity of 104.9 mg/g and 120.7 mg/g for RR56 and RB160, respectively. In addition, thermodynamic studies indicated the endothermic adsorption process for both studied dyes. Moreover, DFT calculations were carried out to obtain more insight into the interactions between the dyes and adsorbent. The results showed that the hydrogen bondings and Van der Waals interactions are dominant forces between the two studied dyes and PPy/CMC composite. Furthermore, the interaction energies calculated by DFT confirmed the experimental adsorption data, where PPy/CMC resulted in higher removal of both dyes compared to PPy. The developed nanocomposite showed considerable reusability up to 3 cylces of the batch adsorption process.


Assuntos
Carboximetilcelulose Sódica/química , Corantes/química , Nanocompostos/química , Adsorção , Compostos Azo , Benzenossulfonatos , Teoria da Densidade Funcional , Cinética , Nanopartículas , Polímeros , Pirróis , Termodinâmica , Poluentes Químicos da Água
14.
PLoS One ; 15(6): e0233952, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32498075

RESUMO

This study aimed to produce cellulose-based conductive fabrics with electrical conductivity and flexibility. Bacterial cellulose (BC) and three chemical cellulose (CC), namely methyl cellulose (MC), hydroxypropyl cellulose (HPMC) and carboxymethyl cellulose (CMC) were in situ polymerized with aniline and the four conductive cellulose fabrics were compared and evaluated. Matrix-assisted laser desorption/ionization time-of-flight mass spectroscopy analysis confirmed that three CC-PANI composites displayed longer and more stable polymerization pattern than BC-PANI because of the different polymerization method: bulk polymerization for BC-PANI and emulsion polymerization for CC-PANI, respectively. The electrical conductivity of BC-PANI and CC-PANI were ranging from 0.962 × 10-2 S/cm to 2.840 × 10-2 S/cm. MC-PANI showed the highest electrical conductivity among the four conductive cellulose fabrics. The flexibility and crease recovery results showed that MC-PANI had the highest flexibility compared to BC-PANI, HPMC-PANI, and CMC-PANI. These results have confirmed that the electrical conductivity and flexibility were influenced by the type of cellulose, and MC-PANI was found to have the best performance in the electrical conductivity and flexibility.


Assuntos
Carboximetilcelulose Sódica/química , Celulose/análogos & derivados , Metilcelulose/química , Polissacarídeos Bacterianos/química , Têxteis , Compostos de Anilina/química , Celulose/química , Elasticidade , Condutividade Elétrica , Nanocompostos/química , Polimerização , Têxteis/análise , Dispositivos Eletrônicos Vestíveis
15.
Carbohydr Polym ; 235: 115944, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32122483

RESUMO

Carboxymethyl cellulose (CMC) based novel functional films containing Chinese chives root extract (CRE) at different concentrations (1, 3 and 5 % in w/w) were successfully fabricated. It was revealed by SEM that higher extract concentration triggered the formation of agglomerates within the film. Tensile strength of the films was decreased from 30.91 to 16.48 MPa. Thickness of films was increased from 43 to 84 µm, while decrease in water solubility from 77.51-52.91 %, swelling degree from 55.74 to 40.37 %, and water vapor permeability from 5.76 to 1.17 10-10 gm-1s-1 Pa-1 was observed. DPPH and ABTS radical scavenging ability of CMC-CRE films was increased from 0 to 58 % and 82 %, respectively. CMC-CRE5 film showed the highest biodegradability of 58.14 %. The film prepared by the addition of CRE into CMC also exhibited good antioxidant and antimicrobial activity indicating that it could be developed as a bio-composite food packaging material for the food industry.


Assuntos
Antibacterianos/farmacologia , Antioxidantes/farmacologia , Carboximetilcelulose Sódica/farmacologia , Cebolinha-Francesa/química , Embalagem de Alimentos , Antibacterianos/química , Antioxidantes/química , Benzotiazóis/antagonistas & inibidores , Compostos de Bifenilo/antagonistas & inibidores , Carboximetilcelulose Sódica/química , China , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Picratos/antagonistas & inibidores , Solubilidade , Vapor , Ácidos Sulfônicos/antagonistas & inibidores , Propriedades de Superfície
16.
Carbohydr Polym ; 235: 115953, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32122489

RESUMO

Adhesion loss of hydrocolloid wound dressings is ubiquitous clinical problem, which seriously reduces the therapeutic efficiency and patient experience. In order to address this problem, the clarification on adhesion loss mechanism and the development of effective alternatives of commercial hydrocolloid dressings are urgent and inevitable. Herein, adhesion loss mechanism of hydrocolloid dressings was investigated using sodium carboxymethyl cellulose (CMC)-filled hydrocolloid dressings exposing to physiological environment as model. The adhesion mechanism and contact angle tests were combined to obtain surface energy of dressings. The results indicated that the dissolution, swelling and exudation of CMC occurred successively (concentration reached 1.607 g/L after 10 h). The effused CMC led to the dramatic increase in surface energy (from 14.5-80.7 mN/m) and adhesion loss appeared. This work explored the origin of adhesion loss of hydrocolloid wound dressings and might promote the designing of hydrocolloid dressings with both excellent humidity control and sustained self-adhesiveness.


Assuntos
Curativos Hidrocoloides , Carboximetilcelulose Sódica/química , Curativos Oclusivos , Pele/química , Adesividade , Humanos , Tamanho da Partícula , Propriedades de Superfície , Aderências Teciduais , Cicatrização
17.
Carbohydr Polym ; 235: 115955, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32122491

RESUMO

Prenyltransferase NovQ immobilized carboxymethyl cellulose magnetic nanoparticles (NCMNs) were successfully synthesized via a valuable approach integrated from nanocomposite preparation, and applied for the production of vitamin K2 using menadione hydroquinol and dimethylallyl diphosphate (DMAPP) as substrates. To investigate the interaction between nanoparticles and NovQ, we characterized the nanocomposite, and revealed that carboxymethyl cellulose (CMC) and Fe3O4 formed a core-shell structure to absorb NovQ in the reaction systems, resulting from the high affinity of immobilized materials. Meanwhile, NCMNs with excellent pH and temperature tolerance, enhanced prenylated activity, and improved stability were found. Molecular docking analysis was also conducted to justify the contribution of multiple amino acids and effect of nanoparticles on catalytic properties of NovQ. Taken together, our study introduces a promising strategy to prepare magnetic nanoparticles and improve the performance of catalyst, which aims for opening new orientations for synthesis of magnetic nanoparticles used for prenyltransferase immobilization.


Assuntos
Carboximetilcelulose Sódica/síntese química , Dimetilaliltranstransferase/química , Nanopartículas de Magnetita/química , Carboximetilcelulose Sódica/química , Dimetilaliltranstransferase/genética , Dimetilaliltranstransferase/metabolismo , Estabilidade Enzimática , Enzimas Imobilizadas/química , Enzimas Imobilizadas/genética , Enzimas Imobilizadas/metabolismo , Tamanho da Partícula , Streptomyces/enzimologia , Propriedades de Superfície
18.
Life Sci ; 253: 117588, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32220621

RESUMO

AIM: The present research work aimed to prepare and characterize nanoparticles of curcumin using polymers from different sources like natural, synthetic and semi-synthetic, and compare their activity for wound healing. Curcumin, BCS class II drug, is a polyphenol with proven wound healing activity. MATERIAL AND METHODS: The curcumin-loaded chitosan and carboxymethylcellulose (CMC) nanoparticles were prepared by ionotropic gelation method. In contrast, poly-lactic co-glycolic acid (PLGA) nanoparticles were prepared by a double emulsion solvent evapouration method. The different sources of polymers include natural (chitosan), synthetic (PLGA) and semi-synthetic CMC were used for the preparation of nanoparticles. KEY FINDINGS: The percentage entrapment efficiency of curcumin-loaded nanoparticles was found to be in the order of polymers PLGA>chitosan>CMC. The in-vitro release study of carboxymethyl cellulose -curcumin nanoparticles was found to be 74.96% for 24 h. The presence of a specific peak of curcumin in all the polymeric nanoparticles specifies drug incorporation in the polymeric matrix. The in-vivo study revealed that curcumin-loaded chitosan nanoparticles fasten the healing process of the wound due to the synergistic effect produced by using a combination of curcumin and chitosan. SIGNIFICANCE: Curcumin-loaded nanoparticles showed significant enhancement in wound healing action by lowering the dose of curcumin and effecting synergistically due to the use of chitosan.


Assuntos
Anti-Inflamatórios não Esteroides/química , Curcumina/química , Nanocápsulas/química , Cicatrização/efeitos dos fármacos , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Carboximetilcelulose Sódica/química , Quitosana/química , Curcumina/farmacologia , Composição de Medicamentos/métodos , Liberação Controlada de Fármacos , Emulsões/química , Humanos , Masculino , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Ratos Wistar
19.
Carbohydr Polym ; 236: 116053, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32172868

RESUMO

A few fruits have short post-harvest life due to high metabolic activity, relatively high water content vulnerability towards microbes and loss of weight during their storage. Carboxymethyl cellulose (CMC)-Guar gum-silver nanocomposite films (CG-Ag0NC) are developed to address these issues. The silver nanoparticles were generated in the CMC-Guar gum matrix through a reduction by Mentha leaves extract. All the films were characterized by UV-vis spectroscopy, FT-IR, TGA, XRD, SEM, TEM, and zeta potential measurements. The antimicrobial activity of CG and CG-Ag0NC was measured by determining their zone inhibition values with ten food pathogenic microbes. The shelf life of CG-Ag0NC films was tested with the model fruit, strawberries, and compared with other packing films. The results are encouraging in terms of freshness, shelf-life and weight loss.


Assuntos
Antibacterianos/farmacologia , Carboximetilcelulose Sódica/química , Galactanos/química , Mananas/química , Nanopartículas Metálicas/química , Nanocompostos/química , Gomas Vegetais/química , Prata/farmacologia , Antibacterianos/química , Bactérias/efeitos dos fármacos , Embalagem de Alimentos , Conservação de Alimentos , Fragaria , Mentha , Testes de Sensibilidade Microbiana , Prata/química , Resistência à Tração
20.
Chemosphere ; 250: 126155, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32105853

RESUMO

Aggregation of nanoparticles (NPs) can hinder the degradative reactivity of particles towards organic pollutants as it reduces available surface area for reaction. This limitation may be circumvented by applying dispersant to improve colloidal stability of nanoparticle suspension. This study examined the removal of hexabromocyclododecane (HBCD), a recently listed persistent organic pollutant, by carboxymethylcellulose (CMC) stabilized nanoscale zerovalent iron (CMC-NZVI) and bimetallic Ni/Fe nanoparticles (CMC-Ni/Fe) under the influence of suspension chemistry. The mass-normalized removal rate constants of HBCD by CMC-Ni/Fe NPs increased with lower particle aggregation. However, the coating could introduce diffusion resistance as HBCD diffused through the CMC layer to the Fe surface. The activation energy was estimated to be 26.8 kJ mol-1, indicating the overall reaction process was neither surface-limited nor diffusion-controlled. The reactivity of CMC-Ni/Fe NPs toward HBCD was not affected by aqueous initial pH substantially. Common monoanions (Cl-, NO3-, and HCO3-) generally enhanced HBCD adsorption but diminished its debromination. The removal rate did not differ significantly among the studied monoanions over a concentration of 2.5-10 mM except HCO3-. Overall, CMC coating can stabilize Ni/Fe NPs, increase their adsorption of HBCD, provide buffer pH capacity, and overcome common inhibition effects of anions in water. These findings suggested the high potential of using CMC-Ni/Fe NPs for in-situ remediation.


Assuntos
Hidrocarbonetos Bromados/química , Nanopartículas Metálicas/química , Poluentes Químicos da Água/química , Adsorção , Carboximetilcelulose Sódica/química , Ferro , Modelos Químicos , Nanopartículas , Água
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