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1.
Int J Biol Macromol ; 258(Pt 1): 128933, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38143071

RESUMO

In this study, zein-gallic acid covalent complex prepared by alkali treatment was utilized as an emulsifier to stabilize cinnamon essential oil (CEO) Pickering emulsion, and the chitosan-based (CZGE) films loaded with CEO Pickering emulsion were prepared by blending. The influences of different contents of CEO Pickering emulsion on the physical properties and biological activities of CZGE films were investigated. The results showed that Pickering emulsion had good compatibility with chitosan matrix and enhanced the interaction between film-forming matrix polymer. In addition, incorporating with CEO Pickering emulsion (15 %, v/v) significantly improved the mechanical and barrier properties of the films, and also enhanced the light transmittance and thermal stability of the films. Furthermore, the loading of emulsion also improved the antioxidant activities of the films and led to the formation of high antimicrobial property against food pathogens, and the slow-release behavior of CEO could effectively extend the biological activity of the films. These results suggested that Pickering emulsion has potential as a loading system and a plasticizer in active packaging, and the feasibility of CZGE film in food packaging.


Assuntos
Quitosana , Nanopartículas , Óleos Voláteis , Zeína , Cinnamomum zeylanicum , Ácido Gálico , Emulsões , Antibacterianos
2.
J Environ Manage ; 345: 118568, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37421718

RESUMO

Phosphate fertilizers have been excessively applied in agricultural production, bringing the risk of phosphorus (P) loss to nearby river systems and low utilization efficiency. In this study, eggshell-modified biochars prepared by pyrolysis of eggshell and corn straw or pomelo peel were applied to soil for enhancing P immobilization and utilization. The structure and properties of modified biochars before and after P adsorption were analyzed using the Brunauer-Emmett-Teller (BET) nitrogen adsorption method, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and scanning electron microscope (SEM). The eggshell-modified biochar performed an excellent adsorption performance for P (up to 200 mg/g), which was well described by the Langmuir model (R2 > 0.969), showing monolayer chemical adsorption with homogenous surface. The Ca(OH)2 appeared on the surface of eggshell modified biochars and changed to Ca5(PO4)3(OH) and CaHPO4(H2O)2 after P adsorption. The release of immobilized P by modified biochar increased with decreased pH. In addition, pot experiments of soybean indicated that the combined application of modified biochar and P fertilizer significantly increased the content of microbial biomass P in soil, raising from 4.18 mg/kg (control group) to 51.6-61.8 mg/kg (treatment group), and plants height increased by 13.8-26.7%. Column leaching experiments showed that P concentration in the leachate decreased by 97.9% with the modified biochar application. This research provides a new perspective that the eggshell-modified biochar could serve as a potential soil amendment for enhancing P immobilization and utilization.


Assuntos
Casca de Ovo , Solo , Animais , Biomassa , Fosfatos , Carvão Vegetal/química , Adsorção , Espectroscopia de Infravermelho com Transformada de Fourier , Cinética
3.
Int J Biol Macromol ; 235: 123914, 2023 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-36870659

RESUMO

In this study, amphiphilic chitosan (NPCS-CA) was synthesized by grafting quaternary phosphonium salt and cholic acid onto the chain of chitosan, aiming to develop an active edible film based on NPCS-CA and polyvinyl alcohol (PVA) incorporated with cinnamon essential oil (CEO) by the casting method. The chemical structure of the chitosan derivative was characterized by FT-IR, 1H NMR and XRD. Through the characterization of FT-IR, TGA, mechanical and barrier properties of the composite films, the optimal proportion of NPCS-CA/PVA was determined as 5/5. And, the tensile strength and elongation at break of the NPCS-CA/PVA (5/5) film with 0.4 % CEO were 20.32 MPa and 65.73 %, respectively. The results revealed that the NPCS-CA/PVA-CEO composite films exhibited an excellent ultraviolet barrier property at 200-300 nm and significantly reduced oxygen permeability, carbon dioxide permeability and water vapor permeability. Furthermore, the antibacterial property of film-forming solutions against E. coli, S. aureus, and C. lagenarium was distinctly improved with the increase of NPCS-CA/PVA proportion. And, the multifunctional films effectively extended the shelf-life of mangoes at 25 °C based on the characterization of surface changes and quality indexes. The NPCS-CA/PVA-CEO films could be developed as biocomposite food packaging material.


Assuntos
Quitosana , Óleos Voláteis , Óleos Voláteis/química , Quitosana/química , Álcool de Polivinil/química , Cinnamomum zeylanicum/química , Espectroscopia de Infravermelho com Transformada de Fourier , Staphylococcus aureus , Escherichia coli , Antibacterianos/farmacologia , Antibacterianos/química , Embalagem de Alimentos/métodos
4.
Int J Biol Macromol ; 236: 123994, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-36914059

RESUMO

The porous structure and hydrophilicity of coating shells affect the nutrient controlled-release performance of castor oil-based (CO) coated fertilizers. In order to solve these problems, in this study, the castor oil-based polyurethane (PCU) coating material was modified with liquefied starch polyol (LS) and siloxane, and a new coating material with cross-linked network structure and hydrophobic surface was synthesized, and used it to prepare the coated controlled-release urea (SSPCU). The results demonstrated that the cross-linked network formed by LS and CO improved the density and reduced the pores on the surface of the coating shells. The siloxane was grafted on the surface of coating shells to improve its hydrophobicity and thus delayed water entry. The nitrogen release experiment indicated that the synergistic effects of LS and siloxane improved the nitrogen controlled-release performance of bio-based coated fertilizers. Nutrient released longevity of SSPCU with 7 % coating percentage reached >63 days. Moreover, the nutrient release mechanism of coated fertilizer was further revealed by the analysis of the release kinetics analysis. Therefore, the results of this study provide a new idea and technical support for development of efficient and environment-friendly bio-based coated controlled-release fertilizers.


Assuntos
Fertilizantes , Siloxanas , Preparações de Ação Retardada/química , Óleo de Rícino , Nitrogênio/química
5.
Int J Biol Macromol ; 224: 1361-1372, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36306905

RESUMO

Quercetin (QCT) has antioxidant, anti-inflammatory, anti-tumor and other important pharmacological activities, but the poor water solubility limits its application. In this work, the amphiphilic dextran (ADEX) was prepared by grafting L-cysteine and octadecylamine onto carboxymethyl dextran with the grafting rate of 21.29 % and 19.35 %. Then, the QCT-loaded nanomicelles (QNMs) were prepared by using ADEX as wall material and the QCT as core material via ultrasonic self-assembly method. The particle size and zeta potential of QNMs were 372 nm and 31.4 mV. Under simulated gastric and simulated intestinal fluids, the cumulative release QNMs were 37.54 % and 52.13 % within 180 min, and the QNMs showed better stability in simulated gastric fluid. The QNMs showed significantly better PTIO, OH and O2- scavenging activities than QCT. In addition, QNMs could effectively down-regulate the expression of pro-inflammatory cytokines and promoted the expression of anti-inflammatory cytokine. The cellular uptake results proved that the QNMs were more easily absorbed by cells than free QCT, indicating that the nano-encapsulation procedure effectively improved the uptake efficiency of QCT by cells.


Assuntos
Antioxidantes , Nanopartículas , Quercetina/farmacologia , Portadores de Fármacos , Micelas , Dextranos
6.
Carbohydr Polym ; 300: 120290, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36372497

RESUMO

In this paper, amphiphilic chitosan and carboxymethyl modified gellan gum were synthesized to develop an active edible fresh-keeping material. The optimal weight ratio of CMCS-g-CA/CMGG was determined as 5:2 through the characterization of Fourier transform infrared (FT-IR), Thermogravimetric analysis (TGA), mechanical and barrier properties of the composite films. In addition, the water vapor permeability and oxygen permeability of CMCS-g-CA/CMGG composite films incorporated with mustard essential oil were all declined, and the antibacterial property of the composite film solutions against E. coli, S. aureus and Bacillus anthracis was distinctly improved with the increase of mustard essential oil (MEO) dosage. Furthermore, the CMCS-g-CA/CMGG + 2.0 µL/mL MEO composite film exhibited an effective preservation on mango fruits during 20 days of storage based on the characterization of surface appearance and quality indexes of fruits. Hence, the multifunctional CMCA-g-CA/CMGG/MEO composite films can be served as a prospective eco-friendly packaging material for fruit preservation.


Assuntos
Quitosana , Mangifera , Óleos Voláteis , Óleos Voláteis/farmacologia , Staphylococcus aureus , Escherichia coli , Espectroscopia de Infravermelho com Transformada de Fourier , Mostardeira , Estudos Prospectivos , Antibacterianos/farmacologia , Permeabilidade , Embalagem de Alimentos
7.
Biomolecules ; 12(11)2022 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-36358951

RESUMO

Creation of bio-multifunctional wound dressings with potent hemostatic, antibacterial, anti-inflammatory, and angiogenesis features for bolstering the healing of full-thickness wounds is sought after for clinical applications. We created bio-multifunctional composite sponges by coupling alginate and chitosan with Sargassum pallidum polysaccharides through electrostatic interactions, calcium ion (Ca2+) crosslinking, and lyophilization. Alginate/chitosan (AC) sponges with different concentrations of Sargassum pallidum polysaccharides were obtained and termed AC, ACS-1%, ACS-2.5%, and ACS-5%. ACS-1% and ACS-2.5% sponges exhibited uniform porosity, high water vapor transmission rate, high water absorption, as well as good hemostatic and antibacterial abilities. ACS-2.5% sponges facilitated wound closure and promoted angiogenesis and re-epithelialization in the dermis. These data suggest that ACS sponges containing a certain amount of Sargassum pallidum polysaccharides could be employed for treatment of full-thickness skin wounds.


Assuntos
Quitosana , Hemostáticos , Sargassum , Quitosana/farmacologia , Alginatos/farmacologia , Polissacarídeos/farmacologia , Antibacterianos/farmacologia
8.
Int J Biol Macromol ; 222(Pt B): 3100-3107, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36244532

RESUMO

Chitosan (CS) is a natural marine polysaccharide with good biocompatibility and biodegradability. But its poor water solubility and antibacterial activity limit its application in fruits preservation. In this study, based on the advantage of quaternary phosphonium salt (QP) and salicylic acid (SA) with good antibacterial activities and different antibacterial mechanisms, a novel antibacterial coating material was synthesized by grafting QP and SA onto CS. With the grafting of SA and QP onto CS, not only the crystallinity of CS molecules decreased and the water solubility improved, but also the antibacterial activity of CS-QP-SA against Escherichia coli and Staphylococcus aureus, and Colletotrichum gloeosporioides (anthracnose) improved by the synergistic effect of QP and SA. After 20 days storage, the mango fruits treated by CS-QP-SA had a weight loss rate of 12.86 %, the fruit decay incidence was 52.00 ± 1.70 %. Hence, the CS-QP-SA films effectively extending the storage time of mango fruits to a certain extent. The results of this study indicated that CS-QP-SA might be a promising preservative for fruits and vegetables.


Assuntos
Quitosana , Mangifera , Quitosana/farmacologia , Antibacterianos/farmacologia , Frutas , Staphylococcus aureus , Escherichia coli , Mangifera/microbiologia , Água/farmacologia
9.
Foods ; 11(12)2022 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-35741931

RESUMO

Honey peach (Prunus persica L.) is highly nutritious; it is an excellent source of sugars, proteins, amino acids, vitamins, and mineral elements. However, it is a perishable climacteric fruit that is difficult to preserve. In this study, "Feicheng" honey peach fruit was used as a test material to investigate the synergistic preservation effect of 1-methylcyclopropene (1-MCP) and laser microporous film (LMF). The peach fruits were fumigated for 24 h with 2 µL L-1 1-MCP, then packed in LMF. In comparison with the control treatment, 1-MCP + LMF treatment markedly decreased the respiration rate, weight loss, and rot rate of peach fruits. Moreover, the combination of 1-MCP and LMF suppressed the increase in soluble solids (SS) and reducing sugars (RS), as well as the decrease in titratable acid (TA) and ascorbic acid (AsA). The combined application also maintained a high protopectin content and low soluble pectin content; it reduced the accumulation of superoxide anions (O2-) and hydrogen peroxide (H2O2). Except in a few samples, the catalase (CAT) and ascorbate peroxidase (APX) activities were higher when treated by 1-MCP + LMF. Conversely, the phenylalanine deaminase (PAL), peroxidase (POD), lipase, lipoxygenase (LOX), polygalacturonase (PG), ß-glucosidase, and cellulase (Cx) activities were lower than in the control. Furthermore, 1-MCP + LMF treatment reduced the relative abundances of dominant pathogenic fungi (e.g., Streptomyces, Stachybotrys, and Issa sp.). The combined treatment improved the relative abundances of antagonistic fungi (e.g., Aureobasidium and Holtermanniella). The results indicated that the co-application of 1-MCP and LMF markedly reduced weight loss and spoilage, delayed the decline of nutritional quality, and inhibited the physiological and biochemical metabolic activities of peach during storage. These changes extended its shelf-life to 28 days at 5 °C. The results provide a reference for the commercial application of this technology.

10.
Int J Biol Macromol ; 212: 11-19, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35598563

RESUMO

In this paper, a cationic photoinitiator (TAS) was used as a catalyst for the ring opening reaction of carboxymethyl chitosan (CMCS) and epoxidized soybean oil (ESO) under UV light to prepare CMCS-g-ESO conjugate, and the structure of the product was characterized by FT-IR, 1H NMR and GPC. Then, the spinosad-loaded microcapsules (SSD@CMCS-g-ESO) were prepared by ultrasonic self-assembly method. The results showed that TAS could catalyze the ring opening reaction of CMCS and ESO under UV-irradiation and the optimum reaction time was 1 h, with the molecular weight of 15,745. The average particle size of SSD@CMCS-g-ESO was about 2.16 µm, and the encapsulation efficiency (EE) and drug loading content (LC) of SSD@CMCS-g-ESO were 85.39 ± 2.05% and 20.17 ± 1.84%, respectively. In vitro release revealed that SSD@CMCS-g-ESO exhibited sustained-release and pH-responsive property, and the accumulative release in the buffer solution of pH = 6.5 and 7.4 was higher than in pH = 9.0. Furthermore, SSD@CMCS-g-ESO had a good antifungal properties against Fusarium oxysporum f. sp. cubense (Foc) compared with the unencapsulated SSD at the same drug dose. This work indicated that photo-chemical reactions could be used to prepare bio-based carrier materials to construct drugs delivery system for targeted treatment of fusarium wilt.


Assuntos
Quitosana , Fusarium , Quitosana/química , Portadores de Fármacos/química , Óleo de Soja , Espectroscopia de Infravermelho com Transformada de Fourier , Raios Ultravioleta
11.
Food Chem ; 387: 132878, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35421653

RESUMO

In this paper, HACC modified with (5-Carboxypentyl) (triphenyl) phosphonium bromide (HA-CS-NP) was synthesized. Then, a multifunctional food packaging composite film with good thermal stability and antibacterial functions was fabricated by HA-CS-NP and poly (vinyl alcohol) (PVA). The tensile strength and elongation at break of HA-CS-NP/PVA composite film at the weight ratio of 3/7 were 20.32 ± 1.02 MPa and 65.73 ± 3.29%, respectively. And, the inhibition rates of HA-CS-NP (0.5%) on Mango C. lagenarium and Papaya C. gloeosporioides on day 6 were up to 80.92 ± 4.12%. Compared with CK group, the weight loss of experimental groups were 23.96 ± 2.46 g/206 ± 7.25 g (mangoes) and 59.45 ± 3.06 g/496 ± 6.37 g (papaya), reduced by 35.76 ± 1.15%. Moreover, the final hardness value of the fruits coated with composite films was 4.94 ± 0.23 kg/cm3 and increased by 20.79 ± 1.04%, and the rot index was reduced by 71.43 ± 3.24%. The multifunctional HA-CS-NP/PVA coating has broad prospects in the application of food packaging.


Assuntos
Quitosana , Antibacterianos , Embalagem de Alimentos , Frutas , Fosfatos , Álcool de Polivinil , Compostos de Amônio Quaternário , Resistência à Tração
12.
Int J Biol Macromol ; 209(Pt A): 344-355, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35413309

RESUMO

As a natural antibacterial agent with pleasant fragrance, citral possesses low aqueous solubility. To improve citral loading in hydrophilic nanofiber, Pickering emulsion electrospinning strategy was proposed for anti-infection dressing development. The in-situ aggerated ß-cyclodextrin-citral inclusion complex particles (ßCPs) were used as emulsion stabilizers, while citral and carboxymethyl chitosan (CMCS)/polyvinyl alcohol (PVA) mixed solutions were used as the inner "dispersed oil phase" and outer "continuous water phase", respectively. The results of electronic microscope investigation shown ßCPs possessed regular cube appearances with a size of 5.5 ± 2.2 µm, which might improve the emulsion storage stability based on visual investigation. Moreover, randomly oriented and bead-on-string nanofibers with ßCPs uniformly distributed could be obtained under optimized compositions and electrospinning parameters. Despite volatilization during electrospinning, nanofibers with high citral loading possessed good antibacterial performance against Staphylococcus aureus and Escherichia coli. In vitro hemolysis test indicated that nanofibers were hemocompatible. In addition, both fiber matrix and citral could promote the proliferation of mouse fibroblast cells. And the permeability of the fibers was adjustable. Thus, CMCS/PVA/ßCPs/citral nanofibers could potentially protect wound from infection. In summary, CMCS/PVA/ßCPs/citral nanofibers seemed to be promising alternatives to conventional wound dressings.


Assuntos
Quitosana , Nanofibras , Monoterpenos Acíclicos , Animais , Antibacterianos/farmacologia , Bandagens , Emulsões , Escherichia coli , Camundongos , Álcool de Polivinil , Cicatrização
13.
Nanomaterials (Basel) ; 11(6)2021 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-34208135

RESUMO

Core-shell nanofibers have great potential for bio-medical applications such as wound healing dressings where multiple drugs and growth factors are expected to be delivered at different healing phases. Compared to monoaxial nanofibers, core-shell nanofibers can control the drug release profile easier, providing sustainable and effective drugs and growth factors for wound healing. However, it is challenging to produce core-shell structured nanofibers with a high production rate at low energy consumption. Co-axial centrifugal spinning is an alternative method to address the above limitations to produce core-shell nanofibers effectively. In this study, a co-axial centrifugal spinning device was designed and assembled to produce core-shell nanofibers for controlling the release rate of ibuprofen and hEGF in inflammation and proliferation phases during the wound healing process. Core-shell structured nanofibers were confirmed by TEM. This work demonstrated that the co-axial centrifugal spinning is a high productivity process that can produce materials with a 3D environment mimicking natural tissue scaffold, and the specific drug can be loaded into different layers to control the drug release rate to improve the drug efficiency and promote wound healing.

14.
Colloids Surf B Biointerfaces ; 202: 111693, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33774518

RESUMO

To increase the solubility and the encapsulation of zinc phthalocyanine (ZnPc) photosensitizer for photodynamic therapy (PDT), a positively charged amphiphilic phosphonium chitosan nanomicelle with multi-benzene structure was developed, and its application to PDT was explored. N-acetyl-l-phenylalanine-(4-carboxybutyl) triphenylphosphonium bromide chitosan (CTPB-CS-NAP), a chitosan derivative with tunable amphiphilicity, was synthesized first. ZnPc was encapsulated in CTPB-CS-NAP at the critical micelle concentration (CMC) of 4.898 mg/L by a hydrophobic self-assembly method to form ZnPc-loaded nanomicelles (ZnPc@CTPB-CS-NAP). The method gives the highest encapsulation efficiency and drug loading of 89.4 % and 22.3 %, respectively. ZnPc@CTPB-CS-NAP is stably dispersed in aqueous solution and shows the average particle size of 103±5 nm. PDT experiments suggest the phototoxicity of ZnPc@CTPB-CS-NAP is much higher than that of ZnPc, but no obvious dark cytotoxicity is observed. Our study has provided a new strategy for improving the photodynamic therapy efficacy of hydrophobic photosensitizer by the encapsulation with chitosan derivative carriers.


Assuntos
Quitosana , Compostos Organometálicos , Fotoquimioterapia , Linhagem Celular Tumoral , Indóis , Isoindóis , Compostos Organometálicos/farmacologia , Fármacos Fotossensibilizantes/farmacologia , Compostos de Zinco
15.
Int J Biol Macromol ; 173: 591-606, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33508359

RESUMO

Chitosan-based thermosensitive hydrogels have been widely used in drug delivery and tissue engineering, but their poor bioactivity has limited their further applications. Integral active oyster peptide microspheres (OPM) with an average particle diameter of 3.9 µm were prepared with high encapsulation efficiency (72.8%) and loading capacity (11.9%), exhibiting desirable sustained release effects. Using catechol functionalized chitosan (CS-C) as the polymeric matrix, OPM as the filler, and ß-sodium glycerophosphate (ß-GP) as a thermal sensitizer, the thermosensitive hydrogel CS-C/OPM/ß-GP was prepared. Besides, the application of the hydrogel on wound healing was studied, and its biosafety was evaluated. The results of cell migration in vitro showed that the cell migration rate of CS-C/OPM/ß-GP reached 97.47 ± 5.41% within 48 h, indicating that the hydrogel accelerated the migration of L929 cells. As demonstrated in the mouse skin wound experiment, CS-C/OPM/ß-GP hydrogel not only inhibited the aggregation of diversified inflammatory cells and accelerated the generation of collagen fibers and new blood vessels of the wound, but also enhanced the synthesis of total protein (TP) in granulation tissue, and up-regulated the expression of Ki-67 and VEGF in the injury, thereby achieving fast wound healing. Safety evaluation results showed that CS-C/OPM/ß-GP hydrogel was not cytotoxic to L929 cells, and the hemolysis ratio was less than 5% within 1 mg/mL. In conclusion, CS-C/OPM/ß-GP hydrogel is expected as a promising medical dressing for wound healing.


Assuntos
Antibacterianos/administração & dosagem , Catecóis/administração & dosagem , Quitosana/administração & dosagem , Ostreidae/metabolismo , Peptídeos/química , Pele/lesões , Cicatrização/efeitos dos fármacos , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Catecóis/química , Catecóis/farmacologia , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Quitosana/química , Quitosana/farmacologia , Glicerofosfatos/química , Hemólise , Hidrogéis , Camundongos , Microesferas , Pele/efeitos dos fármacos
16.
Int J Biol Macromol ; 167: 46-58, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33271181

RESUMO

A novel pH/glutathione (GSH) multi-responsive chitosan nanoparticles (NPs) material has been successfully designed and prepared by a self-assembly/self-crosslinking method for photodynamic therapy (PDT), which overcomes the shortcomings of traditional photosensitizer carriers, such as poor chemical stability, low loading efficiency and single-responsive photosensitizer release. Amphiphilic sulfhydryl chitosan (SA-CS-NAC) is first prepared by modifying chitosan (CS) with stearic acid (SA) and N-acetyl-L-cysteine (NAC), and then subject to self-assembly and self-crosslinking in the presence of photosensitizer, indocyanine green (ICG), to form the ICG-loaded amphiphilic sulfhydryl chitosan nanoparticles (SA-CS-NAC@ICG NPs). The ICG entrapment efficiency and loading efficiency of the NPs are found to be 95.2% and 27.6%, respectively. The multi-responsive ICG release of the NPs to the low pH and high GSH content of the microenvironment in tumor cells is successfully achieved. Under the laser irradiation, the SA-CS-NAC@ICG NPs produce the amount of reactive oxygen species (ROS) twice of that generated by free ICG under the same conditions. The in vitro cell experiment confirmed the strong cellular uptake ability, low biotoxicity and good tumor inhibition of the NPs. Our work has provided a new strategy for the targeted photosensitizer delivery for PDT.


Assuntos
Quitosana/química , Glutationa/química , Concentração de Íons de Hidrogênio , Nanopartículas/química , Fármacos Fotossensibilizantes/química , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Técnicas de Química Sintética , Reagentes de Ligações Cruzadas , Modelos Animais de Doenças , Estabilidade de Medicamentos , Humanos , Espectroscopia de Ressonância Magnética , Camundongos , Micelas , Peso Molecular , Nanopartículas/ultraestrutura , Fotoquimioterapia , Espécies Reativas de Oxigênio/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Ensaios Antitumorais Modelo de Xenoenxerto
17.
Pharmaceutics ; 12(6)2020 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-32521627

RESUMO

Nanofibrous biomaterials have huge potential for drug delivery, due to their structural features and functions that are similar to the native extracellular matrix (ECM). A wide range of natural and polymeric materials can be employed to produce nanofibrous biomaterials. This review introduces the major natural and synthetic biomaterials for production of nanofibers that are biocompatible and biodegradable. Different technologies and their corresponding advantages and disadvantages for manufacturing nanofibrous biomaterials for drug delivery were also reported. The morphologies and structures of nanofibers can be tailor-designed and processed by carefully selecting suitable biomaterials and fabrication methods, while the functionality of nanofibrous biomaterials can be improved by modifying the surface. The loading and releasing of drug molecules, which play a significant role in the effectiveness of drug delivery, are also surveyed. This review provides insight into the fabrication of functional polymeric nanofibers for drug delivery.

18.
Int J Biol Macromol ; 163: 156-166, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32590089

RESUMO

Aiming at high drug loading and controlled drug release in chitosan nanocarriers, this work constructed the photothermal sensitive carboxymethyl chitosan nanospheres carrier by introducing controllable heat-sensitive groups into carboxymethyl chitosan molecules. The combination therapy system based on photothermal-chemotherapy was established by virtue of the good photothermal conversion effect of ICG and the high chemotherapy efficiency of DOX. On the one hand, the carrier owned high drug loading and improved the stability of coated-drug. On the other hand, the nanospheres generated photothermal response through NIR irradiation to improve the drug release amount and to achieve the combined treatment effect of photodynamic therapy and chemotherapy. The structures of the nanospheres were fully characterized by Fourier transform infrared (FT-IR), nuclear magnetic resonance (1H NMR) and scanning electron microscope (SEM). In vitro photothermal tests proved that the nanospheres had excellent light stability and photothermal conversion performance. The cytotoxicity test results showed that the nanospheres had no obvious toxicity, but the drug-loaded nanospheres could effectively inhibit the growth of HepG-2 cells via photo-response to release DOX and ICG for achieving photothermal-chemotherapy under NIR irradiation.


Assuntos
Quitosana/análogos & derivados , Terapia Combinada/métodos , Sistemas de Liberação de Medicamentos/métodos , Nanosferas/química , Resinas Acrílicas/química , Resinas Acrílicas/farmacocinética , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Quitosana/química , Quitosana/farmacocinética , Preparações de Ação Retardada , Doxorrubicina/farmacocinética , Composição de Medicamentos/métodos , Liberação Controlada de Fármacos , Células Hep G2 , Humanos , Verde de Indocianina/farmacocinética , Raios Infravermelhos/uso terapêutico , Espectroscopia de Ressonância Magnética , Microscopia Confocal , Microscopia Eletrônica de Varredura , Fotoquimioterapia/métodos , Espécies Reativas de Oxigênio/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier
19.
Polymers (Basel) ; 13(1)2020 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-33383782

RESUMO

Ultra-fine oil palm ash (OPA) particles were successfully prepared using ultrasonication along with optimal chemical deagglomeration. The influence of chemical treatment by sodium hydroxide (NaOH) solution on the OPA particles was found to be an important factor in enhancing deagglomeration efficiency. The average particle size of the original OPA (41.651 µm) decreased remarkably more than 130 times (0.318 µm) with an obvious increase of Brunauer-Emmet-Teller (BET) surface area after treating the OPA with 3M NaOH, followed by ultrasonication for 30 min. The changes in particle size and surface morphology were investigated using transmission electron microscopy and scanning electron microscopy. Moreover, the chemical functional groups of the untreated and treated OPA showed different patterns of infrared spectra by the presence of sodium carbonate species owing to the effect of NaOH treatment. The incorporation of both untreated and treated OPA in natural rubber by increasing their loading can improve cure characteristics (i.e., reducing optimum cure time and increasing torques) and cure kinetic parameters (i.e., increasing the rate of cure and reducing activation energy). Nevertheless, the strength, degree of reinforcement, and thermal stability of treated OPA as well as wettability between treated OPA particles and NR were greater than that resulting from the untreated OPA.

20.
Carbohydr Polym ; 229: 115431, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31826491

RESUMO

In the current study, a novel CTS/PAA/GO composite polyampholyte physical hydrogel was prepared by the SD-A-SGT method to achieve desired adsorption properties for printing and dyeing wastewater treatment. The hydrogels exhibited controllable and stable structure. The linear PAA significantly improved the swelling and adsorption properties of the hydrogel, and the composition of GO enhanced its mechanical and adsorption properties. The batch adsorption experiments revealed the ability to simultaneously absorb the cationic model dye, MB, and anionic model dye, FY3, with the similar equilibrium adsorption capacities of 296.5±31.7 mg·g-1 and 280.3±23.9 mg·g-1, respectively. The factors affecting the dye adsorption performance, including the hydrogel composition, initial dye concentration and dye solution pH, were investigated. The dye adsorption kinetics was studied and the adsorption mechanisms were proposed. The unique structure and properties of the hydrogel make it a great candidate adsorbent for wastewater treatments.

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