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1.
Int J Mol Sci ; 24(23)2023 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-38069035

RESUMO

Numerous innovative advancements in dressing technology for wound healing have emerged. Among the various types of wound dressings available, hydrogel dressings, structured with a three-dimensional network and composed of predominantly hydrophilic components, are widely used for wound care due to their remarkable capacity to absorb abundant wound exudate, maintain a moisture environment, provide soothing and cooling effects, and mimic the extracellular matrix. Composite hydrogel dressings, one of the evolved dressings, address the limitations of traditional hydrogel dressings by incorporating additional components, including particles, fibers, fabrics, or foams, within the hydrogels, effectively promoting wound treatment and healing. The added elements enhance the features or add specific functionalities of the dressings, such as sensitivity to external factors, adhesiveness, mechanical strength, control over the release of therapeutic agents, antioxidant and antimicrobial properties, and tissue regeneration behavior. They can be categorized as natural or synthetic based on the origin of the main components of the hydrogel network. This review focuses on recent research on developing natural polysaccharide-based composite hydrogel wound dressings. It explores their preparation and composition, the reinforcement materials integrated into hydrogels, and therapeutic agents. Furthermore, it discusses their features and the specific types of wounds where applied.


Assuntos
Anti-Infecciosos , Hidrogéis , Hidrogéis/farmacologia , Cicatrização , Curativos Hidrocoloides , Polissacarídeos/farmacologia
2.
Molecules ; 28(4)2023 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-36838907

RESUMO

Cardiovascular diseases (CVD), such as myocardial infarction (MI), constitute one of the world's leading causes of annual deaths. This cardiomyopathy generates a tissue scar with poor anatomical properties and cell necrosis that can lead to heart failure. Necrotic tissue repair is required through pharmaceutical or surgical treatments to avoid such loss, which has associated adverse collateral effects. However, to recover the infarcted myocardial tissue, biopolymer-based scaffolds are used as safer alternative treatments with fewer side effects due to their biocompatibility, chemical adaptability and biodegradability. For this reason, a systematic review of the literature from the last five years on the production and application of chitosan scaffolds for the reconstructive engineering of myocardial tissue was carried out. Seventy-five records were included for review using the "preferred reporting items for systematic reviews and meta-analyses" data collection strategy. It was observed that the chitosan scaffolds have a remarkable capacity for restoring the essential functions of the heart through the mimicry of its physiological environment and with a controlled porosity that allows for the exchange of nutrients, the improvement of the electrical conductivity and the stimulation of cell differentiation of the stem cells. In addition, the chitosan scaffolds can significantly improve angiogenesis in the infarcted tissue by stimulating the production of the glycoprotein receptors of the vascular endothelial growth factor (VEGF) family. Therefore, the possible mechanisms of action of the chitosan scaffolds on cardiomyocytes and stem cells were analyzed. For all the advantages observed, it is considered that the treatment of MI with the chitosan scaffolds is promising, showing multiple advantages within the regenerative therapies of CVD.


Assuntos
Quitosana , Infarto do Miocárdio , Humanos , Quitosana/química , Alicerces Teciduais/química , Fator A de Crescimento do Endotélio Vascular , Infarto do Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , Engenharia Tecidual
3.
Int J Mol Sci ; 23(20)2022 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-36292962

RESUMO

From the multitude of materials currently available on the market that can be used in the development of microparticles, sodium alginate has become one of the most studied natural anionic polymers that can be included in controlled-release pharmaceutical systems alongside other polymers due to its low cost, low toxicity, biocompatibility, biodegradability and gelatinous die-forming capacity in the presence of Ca2+ ions. In this review, we have shown that through coacervation, the particulate systems for the dispensing of drugs consisting of natural polymers are nontoxic, allowing the repeated administration of medicinal substances and the protection of better the medicinal substances from degradation, which can increase the capture capacity of the drug and extend its release from the pharmaceutical form.


Assuntos
Alginatos , Polímeros , Preparações de Ação Retardada , Gelatina , Sistemas de Liberação de Medicamentos , Ácidos Hexurônicos
4.
Nanomedicine ; 29: 102261, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32621880

RESUMO

Oral administration shows good tolerance in patients. Botanic anticancer drugs without serious side effects have attracted increased attention worldwide. However, oral delivery of natural anticancer drugs faces great challenges due to low solubility, gastrointestinal side effects, first-pass effects, and P-glycoprotein efflux. Here, we loaded the natural polyphenol curcumin (Cc) into natural polysaccharide-cloaked lipidic nanocarriers (Cc@CLNs) to improve the efficacy in small-cell lung cancer (SCLC) associated with oral administration. Compared to other nanoformulations, Cc@CLNs have advantages of simple operation, easy scale-up, low cost, and high safety. Cc@CLNs improve bioavailability by inducing synergistic effects (efficient cell membrane penetration, inherent muco-adhesiveness, resistance to pepsin and trypsin degradation, promoted dissolution, enhanced epithelia/M cellular uptake and inhibition of efflux transporters) and countering the tendency of nanocarriers to aggregate and fuse, which limit lipid-based nanosystems. In this study, we first evaluated the oral bioavailability of Cc@CLNs in rats and their efficacy in H446 tumor-bearing mice. The oral bioavailability increased by 8.94-fold, and the tumor growth inhibition rate doubled compared to that achieved with free Cc. We investigated the action of Cc against SCLC stem cells, and Cc@CLNs greatly enhanced this action. The expression of CD133 and ABCG2 in the Cc@CLNs group decreased by 38.05% and 32.57%, respectively, compared to the respective expression levels in the control.


Assuntos
Produtos Biológicos/farmacologia , Curcumina/farmacologia , Nanopartículas/química , Polifenóis/farmacologia , Carcinoma de Pequenas Células do Pulmão/tratamento farmacológico , Administração Oral , Animais , Produtos Biológicos/química , Linhagem Celular Tumoral , Curcumina/química , Portadores de Fármacos/química , Portadores de Fármacos/farmacologia , Humanos , Lipídeos/química , Lipídeos/farmacologia , Camundongos , Polifenóis/química , Polissacarídeos/química , Polissacarídeos/farmacologia , Ratos , Carcinoma de Pequenas Células do Pulmão/patologia , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Molecules ; 25(13)2020 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-32635318

RESUMO

Injectable hydrogels have attracted growing interests as promising biomaterials for clinical applications, due to their minimum invasive implanting approach and easy-handling performance. Nevertheless, natural biomaterials-based injectable hydrogels with desirable nontoxicity are suffering from limited functions, failing to fulfill the requirements of clinical biomaterials. The development of novel injectable biomaterials with a combination of biocompatibility and adequate functional properties is a growing urgency toward biomedical applications. In this contribution, we report a simple and effective approach to fabricate multi-functional CMC-OSA-DTP hydrogels. Two kinds of natural polysaccharide derived polymers, carboxymethyl chitosan (CMC) and oxidized alginate (OSA) along with 3,3'-dithiopropionic acid dihydrazide (DTP) were utilized to introduce three dynamic covalent bonds. Owing to the existence of triple dynamic bonds, this unique CMC-OSA-DTP hydrogel possessed smart redox and pH stimuli-responsive property, injectability as well as self-healing ability. In addition, the CCK-8 and live/dead assays demonstrated satisfying cytocompatibility of the CMC-OSA-DTP hydrogel in vitro. Based on its attractive properties, this easy-fabricated and multi-functional hydrogel demonstrated the great potential as an injectable biomaterial in a variety of biomedical applications.


Assuntos
Alginatos/química , Neoplasias Ósseas/patologia , Quitosana/análogos & derivados , Hidrogéis/química , Osteossarcoma/patologia , Polímeros/química , Polissacarídeos/administração & dosagem , Materiais Biocompatíveis , Neoplasias Ósseas/tratamento farmacológico , Proliferação de Células , Quitosana/química , Humanos , Hidrogéis/administração & dosagem , Osteossarcoma/tratamento farmacológico , Polissacarídeos/química , Engenharia Tecidual , Células Tumorais Cultivadas
6.
J Sci Food Agric ; 98(8): 2889-2897, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29168567

RESUMO

BACKGROUND: Traditional seed coating agents often contain toxic ingredients, which contaminate the environment and threaten human health. This paper expounds a method of preparing a novel environment-friendly seed coating agent for maize and researches its mechanism of action. The natural polysaccharide polymer, which is the main active ingredient of this environment-friendly seed coating agent, has the characteristics of innocuity and harmlessness, and it can replace the toxic ingredients used in traditional seed coating agents. RESULTS: This environment-friendly seed coating agent for maize was mainly made up of the natural polysaccharide polymer and other additives. The field trials results showed that the control efficacy of Helminthosporium maydis came to 93.72%, the anti-feeding rate of cutworms came to 81.29%, and the maize yield was increased by 17.75%. Besides, the LD50 value (half the lethal dose in rats) of this seed coating agent was 10 times higher than that of the traditional seed coating agents. This seed coating agent could improve the activity of plant protective enzymes (peroxidase, catalase and superoxidase dismutase) and increase the chlorophyll content. CONCLUSION: This seed coating agent has four characteristics of disease prevention, desinsectization, increasing yield and safety. Results of mechanism analyses showed that this seed coating agent could enhance disease control effectiveness by improving plant protective enzymes activity and increase maize yield by improving chlorophyll content. © 2017 Society of Chemical Industry.


Assuntos
Produção Agrícola/métodos , Doenças das Plantas/prevenção & controle , Sementes/química , Zea mays/crescimento & desenvolvimento , Ascomicetos/fisiologia , Catalase/metabolismo , Clorofila/metabolismo , Produção Agrícola/instrumentação , Germinação , Peroxidase/metabolismo , Doenças das Plantas/microbiologia , Proteínas de Plantas/metabolismo , Polissacarídeos/química , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Sementes/microbiologia , Zea mays/química , Zea mays/metabolismo , Zea mays/microbiologia
7.
AAPS PharmSciTech ; 19(6): 2564-2571, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29948987

RESUMO

The major concern with the use of some synthetic excipients is their safety towards biological tissues, hence influencing the reliability of products. With the aim to minimize dependency on highly toxic synthetic excipients, the present study was designed to deliver metronidazole (MNZ) into the colonic region for localized treatment of amoebiasis using natural polysaccharide-based drug delivery. Compression-coated tablets were prepared using water extractable natural polysaccharide from Trigonella foenum-graecum (FG). Physical properties of the tablets were evaluated and dissolution study was performed at pH 1.2, 6.8, and 7.4 with rat cecal material. Results indicate that all batches demonstrated pH-dependent drug release and prevented release into the stomach, allowing traces into the intestine and highest availability into the colon. A significant correlation (r2 = 0.975) was found between the coating levels of extracted polysaccharide and lag time release of drug. Gamma scintigraphy images of in vivo study conducted on human volunteers showed a small intestinal transit time, i.e., 3-5 (4.2 ± 0.4) h and confirmed that the tablets reached the colon within 6-8 h. The present study revealed that the FG polysaccharide-based double compression tablets may be promising colon-specific drug carriers with reduced toxic effects of commonly used synthetic excipients.


Assuntos
Colo/diagnóstico por imagem , Portadores de Fármacos/administração & dosagem , Descoberta de Drogas/tendências , Extratos Vegetais/administração & dosagem , Polissacarídeos/administração & dosagem , Trigonella , Animais , Colo/efeitos dos fármacos , Colo/metabolismo , Portadores de Fármacos/química , Portadores de Fármacos/metabolismo , Sistemas de Liberação de Medicamentos/métodos , Humanos , Extratos Vegetais/química , Extratos Vegetais/metabolismo , Polissacarídeos/química , Polissacarídeos/metabolismo , Cintilografia/métodos , Ratos , Reprodutibilidade dos Testes , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Comprimidos
8.
Pharm Dev Technol ; 22(8): 1001-1011, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27491379

RESUMO

Natural polysaccharides are highly valued and extensively applied in drug delivery system for their desirable physical properties and unique bioactivities. In this work, natural polysaccharides from Bletilla striata (BSP) were successfully extracted and incorporated with Carbopol 940 to prepare hydrogels. Rheological behavior, skin permeation properties and bioactivities of the BSP hydrogels were evaluated. The rheological test showed the better viscoelasticity and physical strength of BSP gels from Carbopol gel. The scanning laser confocal microscope (CLSM) and the trans-epidermal water loss (TEWL) examinations indicated that the BSP hydrogels significantly improved skin permeability. The improvement directly related with the BSP concentration in the gels. Atomic force microscope (AFM) examinations revealed that the BSP hydrogels modified the surface properties of corneocytes and resulted in the promotion effect. Furthermore, bioactivity evaluations indicated the hemostatic activates of BSP hydrogels. In conclusion, this work demonstrates the skin permeation enhancement and plasma coagulation effects of BSP hydrogels, which show great potential in transdermal drug delivery system and wound dressing.


Assuntos
Hidrogéis , Orchidaceae , Polissacarídeos , Humanos , Absorção Cutânea
9.
Drug Dev Ind Pharm ; 42(11): 1763-71, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27032438

RESUMO

OBJECTIVE: This work describes the application of natural plant polysaccharide as pharmaceutical mucoadhesive excipients in delivery systems to reduce the clearance rate through nasal cavity. METHODS: Novel natural polysaccharide (Hibiscus rosasinensis)-based mucoadhesive microspheres were prepared by using emulsion crosslinking method for the delivery of rizatriptan benzoate (RB) through nasal route. Mucoadhesive microspheres were characterized for different parameters and nasal clearance of technetium-99m ((99m)Tc)-radiolabeled microspheres was determined by using gamma-scintigraphy. RESULTS: Their Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) studies showed that the drug was stable during preparation of microspheres. Aerodynamic diameter of microspheres was in the range 13.23 ± 1.83-33.57 ± 3.69 µm. Change in drug and polysaccharide ratio influenced the mucoadhesion, encapsulation efficiency and in-vitro release property. Scintigraphs taken at regular interval indicate that control solution was cleared rapidly from nasal cavity, whereas microspheres showed slower clearance (p < 0.005) with half-life of 160 min. CONCLUSION: Natural polysaccharide-based microspheres achieved extended residence by minimizing effect of mucociliary clearance with opportunity of sustained delivery for longer duration.


Assuntos
Emulsões/química , Hibiscus/química , Mucosa Nasal/química , Polissacarídeos/química , Sistemas de Liberação de Medicamentos , Excipientes , Meia-Vida , Hibiscus/metabolismo , Microesferas , Tamanho da Partícula , Polissacarídeos/metabolismo , Polissacarídeos/farmacocinética , Cintilografia , Difração de Raios X
10.
Int J Biol Macromol ; 271(Pt 2): 132411, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38821798

RESUMO

The tunable properties of hydrogels have led to their widespread use in various biomedical applications such as wound treatment, drug delivery, contact lenses, tissue engineering and 3D bioprinting. Among these applications, natural polysaccharide-based hydrogels, which are fabricated from materials like agarose, alginate, chitosan, hyaluronic acid, cellulose, pectin and chondroitin sulfate, stand out as preferred choices due to their biocompatibility and advantageous fabrication characteristics. Despite the inherent biocompatibility, polysaccharide-based hydrogels on their own tend to be weak in physiochemical and mechanical properties. Therefore, further reinforcement in the hydrogel is necessary to enhance its suitability for specific applications, ensuring optimal performance in diverse settings. Integrating nanomaterials into hydrogels has proven effective in improving the overall network and performance of the hydrogel. This approach also addresses the limitations associated with pure hydrogels. Next, an overview of recent trends in the fabrication and applications of hydrogels was presented. The characterization of hydrogels was further discussed, focusing specifically on the reinforcement achieved with various hydrogel materials used so far. Finally, a few challenges associated with hydrogels by using polysaccharide-based nanomaterial were also presented.


Assuntos
Hidrogéis , Nanoestruturas , Polissacarídeos , Hidrogéis/química , Polissacarídeos/química , Nanoestruturas/química , Materiais Biocompatíveis/química , Humanos , Animais , Engenharia Tecidual/métodos , Sistemas de Liberação de Medicamentos
11.
Int J Biol Macromol ; 264(Pt 1): 130514, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38423440

RESUMO

This paper reports the synthesis, characterization, and properties of chitosan films (CHI) grafted with a natural antifungal agent with the aim of developing active films of natural origin to prevent post-harvest losses of citrus fruit. The antifungal agent was prepared by fermentation using lemon peel (AntiFun-LM), a citrus waste, and grafted on chitosan using different coupling agents (CHI/AntiFun-LM). Bioactive films were prepared by solvent casting. FTIR-ATR and ToF-SIMS analyses provided compelling evidence of the successful grafting process. TGA-DSC demonstrated that the films are stable after grafting. SEM studies showed the continuous and compact surface of the films. WCA measurements proved that CHI/AntiFun-LM films are more hydrophilic than CHI films. Moreover, the CHI/AntiFun-LM films showed stronger UV shielding effect when compared to CHI. The biological evaluation demonstrated that CHI/AntiFun-LM films gained considerable antifungal properties against most fungi responsible for post-harvest decay. Cytotoxicity tests showed that CHI/AntiFun-LM films did not cause any toxic effect against L929 fibroblasts. This study highlights the great potential of chemical grafting of antifungal agents produced from citrus waste to chitosan and preparation of natural-based films to act as a powerful alternative in post-harvest protection of citrus fruit in a perspective of circular economy.


Assuntos
Quitosana , Citrus , Quitosana/química , Antifúngicos/farmacologia , Antifúngicos/química , Citrus/química
12.
Carbohydr Polym ; 336: 122102, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38670773

RESUMO

Skin wounds are susceptible to infection, leading to severe inflammatory reactions that can progress to chronic wounds, ultimately causing significant physical and mental distress to the patient. In this study, we propose an injectable composite hydrogel achieved through one-pot gelation of oxidized xyloglucan (OXG), cationic polyamide ε-poly-l-lysine (EPL), and surface amino-rich silicon nanoparticles (SiNPs). OXG exhibits commendable anti-inflammatory properties and provides crosslinking sites. SiNPs serve as mechanically reinforced crosslinkers, facilitating the construction of a dynamic Schiff base network. SiNPs significantly reduced the gelation time to 3 s and tripled the storage modulus of the hydrogels. Additionally, the combination of EPL and SiNPs demonstrated synergistic antimicrobial activity against both S. aureus and E. coli. Notably, the hydrogel effectively halted liver bleeding within 30 s. The hydrogel demonstrated outstanding shear-thinning and self-healing properties, crucial considerations for the design of injectable hydrogels. Furthermore, its efficacy was evaluated as a wound dressing in a mouse model with S. aureus infection. The results indicated that, compared to commercial products, the hydrogel exhibited a shorter wound healing time, decreased inflammation, thinner epithelium, increased hair follicles, enhanced neovascularization, and more substantial collagen deposition. These findings strongly suggest the promising potential of the proposed hydrogel as an effective wound dressing for the treatment of infected wounds.


Assuntos
Antibacterianos , Escherichia coli , Glucanos , Hidrogéis , Nanopartículas , Polilisina , Staphylococcus aureus , Cicatrização , Xilanos , Glucanos/química , Glucanos/farmacologia , Animais , Cicatrização/efeitos dos fármacos , Xilanos/química , Xilanos/farmacologia , Hidrogéis/química , Hidrogéis/farmacologia , Polilisina/química , Polilisina/farmacologia , Camundongos , Nanopartículas/química , Escherichia coli/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/administração & dosagem , Infecções Estafilocócicas/tratamento farmacológico , Reagentes de Ligações Cruzadas/química , Infecção dos Ferimentos/tratamento farmacológico , Masculino
13.
Int J Biol Macromol ; 266(Pt 1): 131170, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38554906

RESUMO

Skin wound healing is a complex and dynamic process involving hemostasis, inflammatory response, cell proliferation and migration, and angiogenesis. Currently used wound dressings remain unsatisfactory in the clinic due to the lack of adjustable mechanical property for injection operation and bioactivity for accelerating wound healing. In this work, an "all-sugar" hydrogel dressing is developed based on dynamic borate bonding network between the hydroxyl groups of okra polysaccharide (OP) and xyloglucan (XG). Benefiting from the reversible crosslinking network, the resulting composite XG/OP hydrogels exhibited good shear-thinning and fast self-healing properties, which is suitable to be injected at wound beds and filled into irregular injured site. Besides, the proposed XG/OP hydrogels showed efficient antioxidant capacity by scavenging DPPH activity of 73.9 %. In vivo experiments demonstrated that XG/OP hydrogels performed hemostasis and accelerated wound healing with reduced inflammation, enhanced collagen deposition and angiogenesis. This plant-derived dynamic hydrogel offers a facile and effective approach for wound management and has great potential for clinical translation in feature.


Assuntos
Antioxidantes , Hidrogéis , Neovascularização Fisiológica , Polissacarídeos , Cicatrização , Cicatrização/efeitos dos fármacos , Hidrogéis/química , Hidrogéis/farmacologia , Antioxidantes/farmacologia , Antioxidantes/química , Animais , Polissacarídeos/química , Polissacarídeos/farmacologia , Neovascularização Fisiológica/efeitos dos fármacos , Abelmoschus/química , Glucanos/química , Glucanos/farmacologia , Xilanos/química , Xilanos/farmacologia , Camundongos , Ratos , Masculino , Humanos , Angiogênese
14.
Carbohydr Polym ; 345: 122550, 2024 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-39227117

RESUMO

In the realm of natural polysaccharides, hydrogen bonding is a prevalent feature, yet its role in enhancing photocatalytic antimicrobial properties has been underexplored. In this paper, heterojunctions formed by graphene oxide (GO) and ZIF-8 were locked in sodium alginate/ carboxylated cellulose nanocrystals via hydrogen bonding networks, designated as SCGZ. The SCGZ films exhibit superior photocatalytic performance compared to either ZIF-8 or heterojunctions. This enhancement is primarily due to two key factors: firstly, the hydrogen bonding network significantly enhances the transfer of protons and holes, thereby improving the separation efficiency of photo-generated carriers; secondly, the hydrogen bonding between the layers facilitates a more efficient charge transfer, which expedites the movement of electrons from ZIF-8 to GO upon illumination. In vitro studies demonstrated that the SCGZ films possess remarkable antibacterial capabilities, achieving 99.75 % and 99.61 % inhibition rates against S. aureus and E. coli, respectively. In vivo animal experiments have shown that SCGZ films can significantly accelerate the healing process of damaged tissues, with a healing efficiency of up to 90.5 %. This research provides additional insights into the development of natural polysaccharide-based multi­hydrogen bonded macromolecules with enhanced photocatalytic properties.


Assuntos
Alginatos , Antibacterianos , Celulose , Escherichia coli , Grafite , Nanopartículas , Staphylococcus aureus , Cicatrização , Alginatos/química , Alginatos/farmacologia , Celulose/química , Celulose/farmacologia , Nanopartículas/química , Cicatrização/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos/farmacologia , Antibacterianos/química , Escherichia coli/efeitos dos fármacos , Animais , Grafite/química , Grafite/farmacologia , Esterilização/métodos , Ligação de Hidrogênio , Camundongos , Testes de Sensibilidade Microbiana , Catálise
15.
Carbohydr Polym ; 331: 121800, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38388028

RESUMO

Conductive polymers (CPs) are typically insoluble in solvents, and devising biocompatible hydrophilic CPs is challenging and imperative to expand the applications of CPs. Herein, sulfated chitosan (SCS) is used as a green dopant instead of toxic poly(styrene sulfonate) (PSS), and SCS:polypyrrole (SCS:PPy) conductive ink is prepared by in situ polymerization. Due to the complex structure between PPy and SCS polyanion, the synthesized SCS:PPy dispersion forms a well-connected electric pathway and confers superior conductivity, dispersion stability, good film-forming ability, and high electrical stability. As proof of our concept, electrochemical sensing utilizing an SCS:PPy-modified screen-printed carbon electrode (SPCE) was performed towards carbendazim (CBZ). The SCS:PPy on the SPCE surface displayed greater sensitivity to CBZ because the conductive complex structure eased the electrocatalytic action of SCS:PPy by dramatically increasing the current intensity of CBZ oxidation and notably ameliorating stability. The sensor unveils the lowest detection value of 1.02 nM with a linear range of 0.05 to 906 µM for sensing trace CBZ by utilizing the pulse voltammetry technique. Interestingly, this senor shows excellent selectivity towards CBZ due to the formation of substantial interactions between SCS:PPy and CBZ, as demonstrated by molecular simulation studies. Furthermore, this sensor can precisely monitor CBZ in actual fruit and river water samples with satisfactory results. This study sheds light on the design and synthesis of sustainable hydrophilic CPs in the fabrication of sensors.

16.
Int J Biol Macromol ; 273(Pt 2): 132957, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38848837

RESUMO

Food waste resulting from perishable fruits and vegetables, coupled with the utilization of non-renewable petroleum-based packaging materials, presents pressing challenges demanding resolution. This study addresses these critical issues through the innovative development of a biodegradable functional plastic wrap. Specifically, the proposed solution involves the creation of a κ-carrageenan/carboxymethyl chitosan/arbutin/kaolin clay composite film. This film, capable of rapid in-situ formation on the surfaces of perishable fruits, adeptly conforms to their distinct shapes. The incorporation of kaolin clay in the composite film plays a pivotal role in mitigating water vapor and oxygen permeability, concurrently bolstering water resistance. Accordingly, tensile strength of the composite film experiences a remarkable enhancement, escalating from 20.60 MPa to 34.71 MPa with the incorporation of kaolin clay. The composite film proves its efficacy by preserving cherry tomatoes for an extended period of 9 days at 28 °C through the deliberate delay of fruit ripening, respiration, dehydration and microbial invasion. Crucially, the economic viability of the raw materials utilized in the film, coupled with the expeditious and straightforward preparation method, underscores the practicality of this innovative approach. This study thus introduces an easy and sustainable method for preserving perishable fruits, offering a cost-effective and efficient alternative to petroleum-based packaging materials.


Assuntos
Carragenina , Quitosana , Argila , Embalagem de Alimentos , Hidrogéis , Caulim , Solanum lycopersicum , Quitosana/química , Quitosana/análogos & derivados , Caulim/química , Carragenina/química , Argila/química , Embalagem de Alimentos/métodos , Hidrogéis/química , Resistência à Tração , Conservação de Alimentos/métodos , Frutas/química , Permeabilidade
17.
Int J Biol Macromol ; 238: 124113, 2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-36963545

RESUMO

Cartilage tissue regeneration is tremendously tough, it has become a major clinical challenge for the orthopedic medical community. Because of their bionic structure, high water content, biocompatibility, and biodegradability, hydrogels derived from natural polysaccharide are excellent candidates for cartilage tissue engineering. However, these materials often face problems such as poor mechanical strength and excessive swelling, which limit their clinical application. This study used a chemical-physical multi-step cross-linking strategy to create double-network (DN) microcrystalline cellulose (MCC) hydrogels. The hydrogels' intrinsic biomimetic macroporous shape and high water content made them ideal for chondrocyte adhesion and proliferation. The performance requirements for cartilage tissue engineering scaffolds are met by DN hydrogels, which have a sufficiently high compressive strength (4.53 MPa), superior compression recovery, and fatigue resistance, compared to single-network (SN) hydrogels. According to in vitro findings, DN hydrogels could boost cell adhesion and proliferation due to their safe and non-toxic nature. Hydrogels were demonstrated to be stable over the long-term performance, to degrade slowly, and to have strong histocompatibility by in vivo implantation. To construct cartilage tissue engineering scaffold and conduct three-dimensional cell culture, DN hydrogels have significant potential.


Assuntos
Hidrogéis , Engenharia Tecidual , Hidrogéis/farmacologia , Hidrogéis/química , Alicerces Teciduais/química , Cartilagem , Água
18.
Adv Healthc Mater ; 12(24): e2300705, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37029455

RESUMO

Uncontrolled hemorrhage is a leading cause of death, emphasizing the need for novel hemostatic agents. Here, a novel hemostatic polysaccharide hemoadhican (HD) is screened out by analyzing the rheological properties of screened material mixed blood sludges, which is prepared by mixing polysaccharide granules and whole blood to mimic the coagulation in vitro. HD is produced by a bacterial isolate Paenibacillus sp.1229, and the repeating units of HD are →)-α-L-Rhap-(1→3)-ß-D-Glcp-(1→4)[4,6-ethylidene-α-D-Galp-(1→4)-α-D-Glcp-(1→3)]-α-D-Manp-(1→. Compared to chitosan and celox, HD achieves more effective hemostasis in animal models with mouse and rat femoral arteries, rat carotid arteries, and rabbit femoral arteries. Especially, HD maintains an excellent hemostatic capability in animals with heparin-induced hemorrhage diathesis. In vitro experiments show HD granules can quickly absorb a small amount of blood component to create a hemophobic blood sludge resistant to high pressure. The blood sludge firmly adheres to damaged tissue and efficiently repels blood. In vitro experiments show that HD does not actively trigger blood coagulation cascade and is independent of blood conditions including heparin treatment. In addition, HD moisturizes wounds and accelerates wound healing, exhibiting excellent biodegradability, and hemocompatibility. The results indicate that HD is a promising hemostatic material for treating traumatic hemorrhages and uncontrollable surgical bleeding.


Assuntos
Quitosana , Hemostáticos , Ratos , Camundongos , Animais , Coelhos , Hemostáticos/farmacologia , Esgotos , Aderências Teciduais , Coagulação Sanguínea , Hemostasia , Hemorragia/tratamento farmacológico , Polissacarídeos , Heparina/farmacologia
19.
Front Pharmacol ; 14: 1184572, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37497112

RESUMO

Diabetes mellitus (DM) is a group of metabolic diseases characterized by hyperglycemia that can occur in children, adults, elderly people, and pregnant women. Oxidative stress is a significant adverse factor in the pathogenesis of DM, especially type 2 diabetes mellitus (T2DM), and metabolic syndrome. Natural polysaccharides are macromolecular compounds widely distributed in nature. Some polysaccharides derived from edible plants and microorganisms were reported as early as 10 years ago. However, the structural characterization of polysaccharides and their therapeutic mechanisms in diabetes are relatively shallow, limiting the application of polysaccharides. With further research, more natural polysaccharides have been reported to have antioxidant activity and therapeutic effects in diabetes, including plant polysaccharides, microbial polysaccharides, and polysaccharides from marine organisms and animals. Therefore, this paper summarizes the natural polysaccharides that have therapeutic potential for diabetes in the past 5 years, elucidating their pharmacological mechanisms and identified primary structures. It is expected to provide some reference for the application of polysaccharides, and provide a valuable resource for the development of new diabetic drugs.

20.
Carbohydr Polym ; 301(Pt A): 120317, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36436862

RESUMO

Pathogens transmitted through the water environment pose a great threat to human health. Hence developing more reliable and efficient antibacterial materials to eliminate bacterium in water environments is urgent. Herein, we posed a novel strategy of interweaving carboxymethyl chitosan (CMCS) and Ag/Cu-MOFs to construct renewable Ag/Cu-BTC@CMCS composite beads with rapid sterilization, long-term antibacterial effects and high biosafety. Characterizations revealed that CMCS and bimetallic MOFs act as the "warehouses" of metal ions and played key roles in anchoring, storage, delivery, and controlled release of metal ions. The synergistic antibacterial effect achieved by the combination of Ag+ and Cu2+ provides the composite beads with high antibacterial efficiency, resulting in low minimum inhibitory concentrations (0.32 mg/mL against E. coli and 0.16 mg/mL against S. aureus) and over 99.9 % bacteria killing rate. Benefiting from the rapid release of metal ions from polymer chains and the long-term release from MOFs, the composite beads can effectively sterilize the simulated swimming pool water in 2 h and persistently inhibit bacterial reproduction over 48 h, and show a safe level of residual heavy metals because of the chelation of CMCS. This work provides new insights and promises a strategy for the design and commercial application of novel water fungicides.


Assuntos
Quitosana , Metais Pesados , Humanos , Quitosana/farmacologia , Staphylococcus aureus , Escherichia coli , Antibacterianos/farmacologia , Metais Pesados/farmacologia , Água , Esterilização
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