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1.
Mar Drugs ; 21(3)2023 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-36976238

RESUMO

Today, with the salient advancements of modern and smart technologies related to tissue engineering and regenerative medicine (TE-RM), the use of sustainable and biodegradable materials with biocompatibility and cost-effective advantages have been investigated more than before. Alginate as a naturally occurring anionic polymer can be obtained from brown seaweed to develop a wide variety of composites for TE, drug delivery, wound healing, and cancer therapy. This sustainable and renewable biomaterial displays several fascinating properties such as high biocompatibility, low toxicity, cost-effectiveness, and mild gelation by inserting divalent cations (e.g., Ca2+). In this context, challenges still exist in relation to the low solubility and high viscosity of high-molecular weight alginate, high density of intra- and inter-molecular hydrogen bonding, polyelectrolyte nature of the aqueous solution, and a lack of suitable organic solvents. Herein, TE-RM applications of alginate-based materials are deliberated, focusing on current trends, important challenges, and future prospects.


Assuntos
Materiais Biocompatíveis , Engenharia Tecidual , Materiais Biocompatíveis/uso terapêutico , Medicina Regenerativa , Alginatos/uso terapêutico , Hidrogéis
2.
Bioorg Chem ; 119: 105550, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34920337

RESUMO

Infectious diseases caused by new or unknown bacteria and viruses, such as anthrax, cholera, tuberculosis and even COVID-19, are a major threat to humanity. Thus, the development of new synthetic compounds with efficient antimicrobial activity is a necessity. Herein, rationally designed novel multifunctional cationic alternating copolymers were directly synthesized through a step-growth polymerization reaction using a bivalent electrophilic cross-linker containing disulfide bonds and a diamine heterocyclic ring. To optimize the activity of these alternating copolymers, several different diamines and cross-linkers were explored to find the highest antibacterial effects. The synthesized nanopolymers not only displayed good to excellent antibacterial activity as judged by minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) against Staphylococcus aureus, Enterococcus faecalis, Pseudomonas aeruginosa, and Escherichia coli, but also reduced the number of biofilm cells even at low concentrations, without killing mammalian cells. Furthermore, in vivo experiments using infected burn wounds in mice demonstrated good antibacterial activity and stimulated wound healing, without causing systemic inflammation. These findings suggest that the multifunctional cationic nanopolymers have potential as a novel antibacterial agent for eradication of multidrug resistant bacterial infections.


Assuntos
Antibacterianos/farmacologia , Anti-Inflamatórios não Esteroides/farmacologia , Biofilmes/efeitos dos fármacos , Cátions/farmacologia , Polímeros/farmacologia , Cicatrização/efeitos dos fármacos , Aminas/química , Animais , Bactérias/efeitos dos fármacos , Infecções Bacterianas/tratamento farmacológico , Infecções Bacterianas/etiologia , Queimaduras/complicações , COVID-19 , Sobrevivência Celular/efeitos dos fármacos , Reagentes de Ligações Cruzadas , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Células HEK293/efeitos dos fármacos , Humanos , Camundongos , Testes de Sensibilidade Microbiana , Polímeros/química
3.
Molecules ; 27(24)2022 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-36557963

RESUMO

Today, numerous studies have focused on the design of novel scaffolds for tissue engineering and regenerative medicine applications; however, several challenges still exist in terms of biocompatibility/cytocompatibility, degradability, cell attachment/proliferation, nutrient diffusion, large-scale production, and clinical translation studies. Greener and safer technologies can help to produce scaffolds with the benefits of cost-effectiveness, high biocompatibility, and biorenewability/sustainability, reducing their toxicity and possible side effects. However, some challenges persist regarding their degradability, purity, having enough porosity, and possible immunogenicity. In this context, naturally derived cellulose-based scaffolds with high biocompatibility, ease of production, availability, sustainability/renewability, and environmentally benign attributes can be applied for designing scaffolds. These cellulose-based scaffolds have shown unique mechanical properties, improved cell attachment/proliferation, multifunctionality, and enhanced biocompatibility/cytocompatibility, which make them promising candidates for tissue engineering applications. Herein, the salient developments pertaining to cellulose-based scaffolds for neural, bone, cardiovascular, and skin tissue engineering are deliberated, focusing on the challenges and opportunities.


Assuntos
Engenharia Tecidual , Alicerces Teciduais , Celulose , Medicina Regenerativa , Porosidade , Materiais Biocompatíveis/farmacologia
4.
Molecules ; 27(18)2022 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-36144581

RESUMO

Advanced drug delivery micro- and nanosystems have been widely explored due to their appealing specificity/selectivity, biodegradability, biocompatibility, and low toxicity. They can be applied for the targeted delivery of pharmaceuticals, with the benefits of good biocompatibility/stability, non-immunogenicity, large surface area, high drug loading capacity, and low leakage of drugs. Cardiovascular diseases, as one of the primary mortalities cause worldwide with significant impacts on the quality of patients' life, comprise a variety of heart and circulatory system pathologies, such as peripheral vascular diseases, myocardial infarction, heart failure, and coronary artery diseases. Designing novel micro- and nanosystems with suitable targeting properties and smart release behaviors can help circumvent crucial challenges of the tolerability, low stability, high toxicity, and possible side- and off-target effects of conventional drug delivery routes. To overcome different challenging issues, namely physiological barriers, low efficiency of drugs, and possible adverse side effects, various biomaterials-mediated drug delivery systems have been formulated with reduced toxicity, improved pharmacokinetics, high bioavailability, sustained release behavior, and enhanced therapeutic efficacy for targeted therapy of cardiovascular diseases. Despite the existing drug delivery systems encompassing a variety of biomaterials for treating cardiovascular diseases, the number of formulations currently approved for clinical use is limited due to the regulatory and experimental obstacles. Herein, the most recent advancements in drug delivery micro- and nanosystems designed from different biomaterials for the treatment of cardiovascular diseases are deliberated, with a focus on the important challenges and future perspectives.


Assuntos
Doenças Cardiovasculares , Materiais Biocompatíveis , Doenças Cardiovasculares/tratamento farmacológico , Preparações de Ação Retardada , Composição de Medicamentos , Sistemas de Liberação de Medicamentos , Humanos
5.
Analyst ; 146(10): 3087-3100, 2021 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-33999044

RESUMO

Molecularly imprinted polymers (MIPs) have numerous applications in the sensing field, the detection/recognition of virus, the structure determination of proteins, drug delivery, artificial/biomimetic antibodies, drug discovery, and cell culturing. There are lots of conventional methods routinely deployed for the analysis/detection of viral infections and pathogenic viruses, namely enzyme immunoassays, immunofluorescence microscopy, polymerase chain reaction (PCR) and virus isolation. However, they typically suffer from higher costs, low selectivity/specificity, false negative/positive results, time consuming procedures, and inherent labor intensiveness. MIPs offer promising potential for viral recognition/detection with high target selectivity, sensitivity, robustness, reusability, and reproducible fabrication. In terms of virus detection, selectivity and sensitivity are critical parameters determined by the template; additionally, the analytical detection and evaluation of viruses must have considerably low detection limits. The virus-imprinted polymer-based innovative strategies with enough specificity, convenience, validity, and reusability features for the detection/recognition of a wide variety of viruses, can provide attractive capabilities for reliable screening with minimal false negative/positive results that is so crucial for the prevention and control of epidemic and pandemic viral infections. However, in the process of imprinting viruses, critical factors such as size of the target, solubility, fragility, and compositional complexity should be analytically considered and systematically evaluated. In this review, recent advancements regarding the applications of MIPs and pertinent virus imprinting techniques for the detection of viruses, as well as their current significant challenges and future perspectives, are deliberated.


Assuntos
Impressão Molecular , Vírus , Biomimética , Polímeros Molecularmente Impressos , Polímeros
6.
Molecules ; 25(10)2020 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-32414061

RESUMO

Chitosan has been used for biomedical applications in recent years, primarily because of its biocompatibility. A chitosan membrane with a 30 µm thickness was prepared and investigated for its surface modification using methane ions. Methane ions were implanted into the chitosan membrane using a Kaufman ion source; bombardment was accomplished using three accelerating voltages of ion beams-30, 55, and 80 keV. The influence of the ion bombardment on morphology, crystallinity, and hydrophilicity was investigated. Attenuated total reflectance Fourier-transform infrared (ATR-FTIR) spectroscopy analysis showed that a triplet bond appeared after the implantation of methane ions (acceleration voltage: 80 keV), culminating in the creation of a more amorphous membrane structure. The analyses of atomic force microscopy (AFM) images showed that, with the increase in bombardment energy, the roughness of the surface changed. These results revealed that ion bombardment improved the hydrophilicity of the membranes and the water fluxes of chitosan membranes altered after methane ion bombardment.


Assuntos
Quitosana/química , Membranas Artificiais , Metano/química , Interações Hidrofóbicas e Hidrofílicas , Microscopia de Força Atômica , Espectroscopia de Infravermelho com Transformada de Fourier
7.
Bioprocess Biosyst Eng ; 42(12): 2007-2014, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31451901

RESUMO

Simpler and biocompatible greener approaches for the assembly of nanoparticles (NPs) have been the focus lately which have minimum environmental damage and often entails the use of natural biomolecules to synthesize NPs. Such greener synthesis of nanoparticles has capitalized on the use of microbes, fungi, and plants using biological resources. In this study, Periplaneta americana (American cockroach) wings' extract (chitin-rich) is studied as a novel biomaterial for the first time to synthesize silver NPs (less than 50 nm); chitin is the second most abundant polymer after cellulose on earth. The physicochemical properties of these NPs were analyzed using UV-visible spectroscopy, X-ray diffraction, and transmission electron microscopy (TEM). The insecticidal effect of ensuing NPs was examined on the mortality of Aphis gossypii under laboratory conditions; 48 h after treatments of A. gossypii with silver NPs (100 µg/ml), the mortality rate in treated aphids was about 40% (an average), while an average percentage of losses in the control sample was about 10%. These results indicate the lethal effect of green-synthesized silver NPs on A. gossypii, in vitro. Greener synthesis of silver nanoparticles using American cockroach wings and their insecticidal activities.


Assuntos
Materiais Biocompatíveis/química , Inseticidas/farmacologia , Nanopartículas Metálicas/química , Prata/química , Asas de Animais/química , Animais , Celulose/química , Quitina/química , Química Verde/métodos , Microbiologia Industrial/métodos , Microscopia Eletrônica de Transmissão , Periplaneta/química , Polímeros/química , Espectrofotometria Ultravioleta , Difração de Raios X
8.
Int J Mol Sci ; 20(13)2019 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-31284439

RESUMO

Radio frequency plasma is one of the means to modify the polymer surface namely in the activation of polypropylene membranes (PPM) with O2 plasma. Activated membranes were deposited with TiO2 nanoparticles by the dip coating method and the bare sample and modified sample (PPM5-TiO2) were irradiated by UV lamps for 20-120 min. Characterization techniques such as X-ray diffraction (XRD), Attenuated total reflection technique- Fourier transform infrared spectroscopy (ATR-FTIR), Thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS), Scanning electron microscope (SEM) and water contact angle (WCA) measurements were applied to study the alteration of ensuing membrane surface properties which shows the nanoparticles on the sample surface including the presence of Ti on PPM. The WCA decreased from 135° (PPM) to 90° (PPM5-TiO2) and after UV irradiation, the WCA of PPM5-TiO2 diminished from 90° to 40°.


Assuntos
Membranas Artificiais , Nanopartículas/química , Oxigênio/química , Gases em Plasma/química , Polipropilenos/química , Titânio/química , Espectroscopia Fotoeletrônica , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Termogravimetria , Água/química , Molhabilidade , Difração de Raios X
9.
Chem Soc Rev ; 46(22): 6675-6686, 2017 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-29034941

RESUMO

This tutorial review assesses the available and possible strategies for attaining higher selectivity and yield of value-added chemicals from lignin using nanocatalysts embedded in a photomicroreactor. The design of the photomicroreactor, the choice of photocatalysts and the techniques for assembling the catalysts in such confined spaces are crucial elements. Lignin, a predominant industrial byproduct and pollutant, has been recognized today as a rich reservoir for aromatic chemicals and a prominent resource. The conventional batch photocatalytic studies on lignin, often using dissolved lignin under alkaline conditions, often generates a wide range of valuable organic chemicals which find applications in the pharmaceutical, food processing, cosmetic and fine chemical industries. The role of photocatalysis in such lignin depolymerizations is questionable as the dissolution procedure initiates fragmentation of lignin prior to light exposure. The complexity of the lignin structure also impedes necessary and decisive information to understand the reaction mechanism during such reactions in batch photoreactors. Considering these facts, photocatalysis studies on lignin entail a thoughtful reevaluation and focus on understanding the role of photocatalysis in the product generation and authenticating the implicated reaction mechanisms. The development of a photocatalytic system for lignin depolymerization in a continuous microreactor is a superior approach for the generation of valuable products emanating from lignin depolymerization and the successful execution of such strategies can pave the way for the commercialization of bio-based chemicals.


Assuntos
Lignina/química , Microfluídica/instrumentação , Nanoestruturas/química , Processos Fotoquímicos , Catálise , Luz , Compostos Orgânicos/química
10.
Int J Biol Macromol ; 246: 125763, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37429338

RESUMO

Overusing pesticides, fertilizers, and synthetic dyes has significantly increased their presence in various parts of the environment. The transportation of these pollutants into agricultural soil and water through rivers, soils, and groundwater has seriously threatened human and ecosystem health. Applying techniques and materials to clean up agricultural sources from pesticides, heavy metals (HMs), and synthetic dyes (SDs) is one of the major challenges in this century. The sorption technique offers a viable solution to remediate these chemical pollutants (CHPs). Cellulose-based materials have become popular in nano and micro scales because they are widely available, safe to use, biodegradable, and have a significant ability to absorb substances. Nanoscale cellulose-based materials exhibit greater capacity in absorbing pollutants compared to their microscale counterparts because they possess a larger surface area. Many available hydroxyl groups (-OH) and chemical and physical modifications enable the incorporation of CHPs on to cellulose-based materials. Following this potential, this review aims to comprehensively summarize recent advancements in the field of nano- and micro-cellulose-based materials as effective adsorbents for CHPs, given the abundance of cellulosic waste materials from agricultural residues. The recent developments pertaining to the enhancement of the sorption capacity of cellulose-based materials against pesticides, HMs, and SDs, are deliberated.


Assuntos
Poluentes Ambientais , Metais Pesados , Praguicidas , Poluentes do Solo , Poluentes Químicos da Água , Humanos , Celulose/química , Ecossistema , Poluentes Químicos da Água/química , Solo , Corantes , Metais Pesados/química , Adsorção
11.
J Mater Chem B ; 11(44): 10538-10565, 2023 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-37909361

RESUMO

Polysaccharides have found extensive utilization as biomaterials in drug delivery systems owing to their remarkable biocompatibility, simple functionalization, and inherent biological properties. Within the array of polysaccharide-based biomaterials, there is a growing fascination for self-assembled polysaccharide nanogels (NG) due to their ease of preparation and enhanced appeal across diverse biomedical appliances. Nanogel (or nanohydrogel), networks of nanoscale dimensions, are created by physically or chemically linking polymers together and have garnered immense interest as potential carriers for delivering drugs due to their favorable attributes. These include biocompatibility, high stability, the ability to adjust particle size, the capacity to load drugs, and their inherent potential to modify their surface to actively target specific cells or tissues via the attachment of ligands that can recognize corresponding receptors. Nanogels can be engineered to respond to specific stimuli, such as pH, temperature, light, or redox conditions, allowing controlled release of the encapsulated drugs. This intelligent targeting capability helps prevent drug accumulation in unintended tissues and reduces the potential side effects. Herein, an overview of nanogels is offered, comprising their methods of preparation and the design of stimulus-responsive nanogels that enable controlled release of drugs in response to specific stimuli.


Assuntos
Sistemas de Liberação de Medicamentos , Polissacarídeos , Nanogéis/química , Preparações de Ação Retardada , Sistemas de Liberação de Medicamentos/métodos , Materiais Biocompatíveis
12.
Acc Chem Res ; 44(7): 469-78, 2011 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-21526846

RESUMO

Over the past 25 years, microwave (MW) chemistry has moved from a laboratory curiosity to a well-established synthetic technique used in many academic and industrial laboratories around the world. Although the overwhelming number of MW-assisted applications today are still performed on a laboratory (mL) scale, we expect that this enabling technology may be used on a larger, perhaps even production, scale in conjunction with radio frequency or conventional heating. Microwave chemistry is based on two main principles, the dipolar mechanism and the electrical conductor mechanism. The dipolar mechanism occurs when, under a very high frequency electric field, a polar molecule attempts to follow the field in the same alignment. When this happens, the molecules release enough heat to drive the reaction forward. In the second mechanism, the irradiated sample is an electrical conductor and the charge carriers, ions and electrons, move through the material under the influence of the electric field and lead to polarization within the sample. These induced currents and any electrical resistance will heat the sample. This Account summarizes a microwave (MW)-assisted synthetic approach for producing silver nanostructures. MW heating has received considerable attention as a promising new method for the one-pot synthesis of metallic nanostructures in solutions. Researchers have successfully demonstrated the application of this method in the preparation of silver (Ag), gold (Au), platinum (Pt), and gold-palladium (Au-Pd) nanostructures. MW heating conditions allow not only for the preparation of spherical nanoparticles within a few minutes but also for the formation of single crystalline polygonal plates, sheets, rods, wires, tubes, and dendrites. The morphologies and sizes of the nanostructures can be controlled by changing various experimental parameters, such as the concentration of metallic salt precursors, the surfactant polymers, the chain length of the surfactant polymers, the solvents, and the operation reaction temperature. In general, nanostructures with smaller sizes, narrower size distributions, and a higher degree of crystallization have been obtained more consistently via MW heating than by heating with a conventional oil-bath. The use of microwaves to heat samples is a viable avenue for the greener synthesis of nanomaterials and provides several desirable features such as shorter reaction times, reduced energy consumption, and better product yields.


Assuntos
Nanopartículas Metálicas/química , Micro-Ondas , Prata/química , Carboidratos/química , Cristalização , Ouro/química , Platina/química , Polímeros/química , Solventes/química , Tensoativos/química
13.
Sci Rep ; 12(1): 17986, 2022 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-36289249

RESUMO

A nanomagnetic hydrophilic heterogeneous copper catalyst, termed γ-Fe2O3@PEG@PAMAM G0-Cu, has been successfully prepared and characterized using FT-IR, XRD, FE-SEM, TEM, EDX, mapping, TGA/DTG, VSM and ICP analyses. The catalyst displayed excellent activity for the palladium-free Sonogashira cross coupling reaction of various aryl iodides and bromides with phenylacetylene derivatives in pure water. The presence of polyethylene glycol coupled with hydrophilic character of the Cu-catalyst adorned on γ-Fe2O3 MNPs provides the ready dispersion of the catalyst particles in water, leading to higher catalytic performance as well as facile catalyst recovery via simple magnetic decantation. The recovered catalyst was reused for at least six successive runs with little reduction in its catalytic activity and any noticeable changes in its structure. The use of water as a green solvent, without requiring any additive or organic solvent, as well as the exploitation of abundant and low-cost copper catalyst instead of expensive Pd catalyst along with the catalyst recovery and scalability, make this method favorable from environmental and economic points of view for the Sonogashira coupling reaction.


Assuntos
Cobre , Nanopartículas de Magnetita , Cobre/química , Iodetos , Brometos , Espectroscopia de Infravermelho com Transformada de Fourier , Polietilenoglicóis , Água , Solventes
14.
Int J Biol Macromol ; 222(Pt A): 1589-1604, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36202330

RESUMO

Biological biocides have the potential to reduce plant biotic stresses and boost development, but they tend to be unstable and degrade quickly. BCAs inhibit plant diseases and enhance crop productivity while being eco-friendly. Encapsulation research has increased in recent decades in response to the growing need for BCAs. These formulations can address the difficulties of free-form formulations. They can improve the efficacy of BCAs by prolonging their shelf life and offering the controlled release of biological components. Using a novel approach, they can be a potential platform for controlling biotic stressors, especially plant pathogens. Chitosan and alginate are two important biopolymers with great potential in enclosing BCAs. These can also be used alone for encapsulation, but their application in composite form eliminates the disadvantages of using them alone. However, several other biopolymers have significant roles in formulating BCAs, such as gums, gelatin, starch, and pectin. Given the amazing potential of these new formulations, this comprehensive review highlights more recent developments about encapsulating BCAs based on nano and micro-materials and their appliances in reducing plant biotic stressors. These prospects might provide the foundation for future opportunities to expand the efficacy and application BCAs by formulation technologies to combat plant pathogens.


Assuntos
Quitosana , Quitosana/farmacologia , Alginatos , Plantas , Estresse Fisiológico , Biopolímeros/farmacologia
15.
Chemosphere ; 302: 134825, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35526681

RESUMO

The use of a cheap and effective adsorption approach based on biomass-activated carbon (AC) to remediate heavy metal contamination is clearly desirable for developing countries that are economically disadvantaged yet have abundant biomass. Therefore, this review provides an update of recent works utilizing biomass waste-AC to adsorb commonly-encountered adsorbates like Cr, Pb, Cu, Cd, Hg, and As. Various biomass wastes were employed in synthesizing AC via two-steps processing; oxygen-free carbonization followed by activation. In recent works related to the activation step, the microwave technique is growing in popularity compared to the more conventional physical/chemical activation method because the microwave technique can ensure a more uniform energy distribution in the solid adsorbent, resulting in enhanced surface area. Nonetheless, chemical activation is still generally preferred for its ease of operation, lower cost, and shorter preparation time. Several mechanisms related to heavy metal adsorption on biomass wastes-AC were also discussed in detail, such as (i) - physical adsorption/deposition of metals, (ii) - ion-exchange between protonated oxygen-containing functional groups (-OH, -COOH) and divalent metal cations (M2+), (iii) - electrostatic interaction between oppositely-charged ions, (iv) - surface complexation between functional groups (-OH, O2-, -CO-NH-, and -COOH) and heavy metal ions/complexes, and (v) - precipitation/co-precipitation technique. Additionally, key parameters affecting the adsorption performance were scrutinized. In general, this review offers a comprehensive insight into the production of AC from lignocellulosic biomass and its application in treating heavy metals-polluted water, showing that biomass-originated AC could bring great benefits to the environment, economy, and sustainability.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Adsorção , Biomassa , Carvão Vegetal , Íons , Cinética , Lignina
16.
J Mater Chem B ; 10(31): 5873-5912, 2022 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-35880440

RESUMO

Tannic acid (TA), a natural polyphenol, is a hydrolysable amphiphilic tannin derivative of gallic acid with several galloyl groups in its structure. Tannic acid interacts with various organic, inorganic, hydrophilic, and hydrophobic materials such as proteins and polysaccharides via hydrogen bonding, electrostatic, coordinative bonding, and hydrophobic interactions. Tannic acid has been studied for various biomedical applications as a natural crosslinker with anti-inflammatory, antibacterial, and anticancer activities. In this review, we focus on TA-based hydrogels for biomaterials engineering to help biomaterials scientists and engineers better realize TA's potential in the design and fabrication of novel hydrogel biomaterials. The interactions of TA with various natural or synthetic compounds are deliberated, discussing parameters that affect TA-material interactions thus providing a fundamental set of criteria for utilizing TA in hydrogels for tissue healing and regeneration. The review also discusses the merits and demerits of using TA in developing hydrogels either through direct incorporation in the hydrogel formulation or indirectly via immersing the final product in a TA solution. In general, TA is a natural bioactive molecule with diverse potential for engineering biomedical hydrogels.


Assuntos
Hidrogéis , Taninos , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Hidrogéis/química , Polifenóis/farmacologia , Taninos/química , Cicatrização
17.
J Control Release ; 350: 175-192, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35914615

RESUMO

Chitosan is a natural polymer with acceptable biocompatibility, biodegradability, and mechanical stability; hence, it has been widely appraised for drug and gene delivery applications. However, there has been no comprehensive assessment to tailor-make chitosan cross-linkers of various types and functionalities as well as complex chitosan-based semi- and full-interpenetrating networks for drug delivery systems (DDSs). Herein, various fabrication methods developed for chitosan hydrogels are deliberated, including chitosan crosslinking with and without diverse cross-linkers. Tripolyphosphate, genipin and multi-functional aldehydes, carboxylic acids, and epoxides are common cross-linkers used in developing biomedical chitosan for DDSs. Methods deployed for modifying the properties and performance of chitosan hydrogels, via their composite production (semi- and full-interpenetrating networks), are also cogitated here. In addition, recent advances in the fabrication of advanced chitosan hydrogels for drug delivery applications such as oral drug delivery, transdermal drug delivery, and cancer therapy are discussed. Lastly, thoughts on what is needed for the chitosan field to continue to grow is also debated in this comprehensive review article.


Assuntos
Quitosana , Aldeídos , Ácidos Carboxílicos , Sistemas de Liberação de Medicamentos/métodos , Compostos de Epóxi , Hidrogéis , Polímeros
18.
Carbohydr Polym ; 251: 116986, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33142558

RESUMO

Natural biopolymers, polymeric organic molecules produced by living organisms and/or renewable resources, are considered greener, sustainable, and eco-friendly materials. Natural polysaccharides comprising cellulose, chitin/chitosan, starch, gum, alginate, and pectin are sustainable materials owing to their outstanding structural features, abundant availability, and nontoxicity, ease of modification, biocompatibility, and promissing potentials. Plentiful polysaccharides have been utilized for making assorted (nano)catalysts in recent years; fabrication of polysaccharides-supported metal/metal oxide (nano)materials is one of the effective strategies in nanotechnology. Water is one of the world's foremost environmental stress concerns. Nanomaterial-adorned polysaccharides-based entities have functioned as novel and more efficient (nano)catalysts or sorbents in eliminating an array of aqueous pollutants and contaminants, including ionic metals and organic/inorganic pollutants from wastewater. This review encompasses recent advancements, trends and challenges for natural biopolymers assembled from renewable resources for exploitation in the production of starch, cellulose, pectin, gum, alginate, chitin and chitosan-derived (nano)materials.


Assuntos
Biopolímeros , Nanoestruturas , Purificação da Água/métodos , Adsorção , Alginatos , Catálise , Celulose , Quitina , Quitosana , Conservação dos Recursos Hídricos , Química Verde , Nanoestruturas/química , Nanotecnologia , Pectinas , Amido , Águas Residuárias/química , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificação
19.
ACS Appl Bio Mater ; 4(6): 5106-5121, 2021 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-35007059

RESUMO

A one-pot and facile method with assistance of high gravity was applied for the synthesis of inorganic two-dimensional MOF-5 embedded MXene nanostructures. The innovative inorganic MXene/MOF-5 nanostructure was applied in co-delivery of drug and gene, and to increase its bioavailability and interaction with the pCRISPR, the nanomaterial was coated with alginate and chitosan. The polymer-coated nanosystems were fully characterized, and the sustained DOX delivery and comprehensive cytotoxicity studies were conducted on the HEK-293, PC12, HepG2, and HeLa cell lines, demonstrating acceptable and excellent cell viability at both very low (0.1 µg.mL-1) and high (10 µg·mL-1) concentrations. The chitosan-coated nanocarriers showed superior relative cell viability compared to others, more than 60% on average of relative cell viability in all of the cell lines. Then, alginate-coated nanocarriers ranked at second place on the higher relative cell viability, more than 50% on average for all of the cell lines. Also, MTT results showed a complete dose-dependence, and by increasing the time of treatment from 24 to 72 h, the relative cell viability decreased by a meaningful slope; however, this decrease was optimized by coating the nanocarrier with chitosan and alginate. The nanosystems were also tagged with pCRISPR to analyze the potential application in the co-delivery of drug/gene. CLSM images of the HEK-293 and HeLa cell lines unveiled successful delivery of pCRISPR into the cells, and the enhanced green fluorescent protein (EGFP) reached up to ca. 26% for the HeLa cell line. Also, a considerable drug payload of 35.7% was achieved, which would be because of the interactions between the nanocarrier and the doxorubicin. In this unprecedented report pertaining to the synthesis of MXene assisted by a MOF and high-gravity technique, the methodology and the optimized ensuing MXene/MOF-5 nanosystems can be further developed for the co-delivery of drug/gene in animal models.


Assuntos
Quitosana , Alginatos , Animais , Quitosana/química , Doxorrubicina/farmacologia , Células HEK293 , Células HeLa , Humanos , Polímeros/química
20.
Int J Biol Macromol ; 171: 130-149, 2021 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-33412195

RESUMO

This review summarizes and broadly classifies all of the major sustainable natural carbohydrate bio-macromolecular manifestations in nature - from botanical (cellulose, starch, and pectin), seaweed (alginate, carrageenan, and agar), microbial (bacterial cellulose, dextran, and pullulan), and animal (hyaluronan, heparin, chitin, and chitosan) sources - that have been contrived into electrospun fibers. Furthermore, a relative study of these biomaterials for the fabrication of nanofibers by electrospinning and their characteristics viz. solution behavior, blending nature, as well as rheological and fiber attributes are discussed. The potential multidimensional applications of nanofibers (filtration, antimicrobial, biosensor, gas sensor, energy storage, catalytic, and tissue engineering) originating from these polysaccharides and their major impacts on the properties, functionalities, and uses of these electrospun fibers are compared and critically examined.


Assuntos
Materiais Biocompatíveis/química , Nanofibras/química , Nanotecnologia/métodos , Engenharia Tecidual/métodos , Ágar/química , Alginatos/química , Animais , Carragenina/química , Celulose/química , Quitina/química , Quitosana/química , Dextranos/química , Técnicas Eletroquímicas , Glucanos/química , Heparina/química , Humanos , Ácido Hialurônico/química , Nanofibras/ultraestrutura , Pectinas/química , Amido/química
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