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1.
Int J Biol Macromol ; 265(Pt 1): 130758, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38462106

RESUMO

Diclofenac sodium (DCF) was reported as an important emerging environmental pollutant and its removal from wastewater is very urgent. In this study, different alkyl substituted ionic liquids (1-alkyl -3-vinyl- imidazolium bromide [CnVIm]Br, n = 4, 6, 8, 10, 12) functionalized tragacanth gum (TG-CnBr) are prepared by radiation induced grafting and crosslinking polymerization. The adsorption behaviors of ionic liquids functionalized tragacanth gum for diclofenac sodium from aqueous solutions are examined. The adsorption capacity of TG-CnBr for diclofenac sodium increases with the increasing of alkyl chain length of the imidazolium cation and the hydrophobicity of the hydrogels. The maximum adsorption capacity by TG-C12Br for diclofenac sodium at 30, 40 and 50 °C were 327.87, 310.56 and 283.29 mg/g, respectively. The adsorption of TG-C12Br towards diclofenac sodium was little decreased with NaCl increasing. The removal efficiency was still remained 94.55 % within 5 adsorption-desorption cycles by 1 M HCl. Also, the adsorption mechanism including electrostatic attraction, hydrophobic interaction, hydrogen bonding, and π - π interaction was proposed.


Assuntos
Líquidos Iônicos , Tragacanto , Poluentes Químicos da Água , Diclofenaco/química , Tragacanto/química , Hidrogéis/química , Água , Adsorção , Poluentes Químicos da Água/química
2.
Int J Biol Macromol ; 257(Pt 1): 128343, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38007020

RESUMO

Herein, glutamic acid, lysine, arginine and glycine grafted tragacanth gum (TG) were synthesized and designated as TG-Glu, TG-Lys, TG-Arg, and TG-Gly, respectively. The corresponding degrees of substitution (DS) were 0.212, 0.255, 0.394, and 0.169. Thermal, antioxidant, and antibacterial properties of synthesized amino acid-grafted tragacanth gum (ATG) were investigated. The results suggested that the grafting of amino acids onto TG has the potential to alter its thermal properties. When compared with TG and amino acid alone, ATG exhibited significantly enhanced antioxidant and antibacterial properties, with these properties being concentration-dependent. At a concentration of 2 mg/mL for TG-Glu and 3 mg/mL for TG-Arg, TG-Gly, and TG-Lys, the scavenging rate for 2,2'-hypoazido-3-ethylbenzothiazoline sulfonate (ABTS) radical reached 100 %. On the other hand, the scavenging rate of TG-Glu for hydroxyl radical achieved 100 % even at a concentration as low as 1 mg/mL. These properties were accompanied by an increase in reducing force and a notable improvement in the ability to scavenge superoxide anion (O2-). Moreover, the combination of amino acids and TG represents a promising approach to enhance the antimicrobial activities of TG, with the bacteriostatic rate reaching 100 %. Consequently, ATG shows promise as a novel agent for both antioxidation and antimicrobial applications.


Assuntos
Anti-Infecciosos , Tragacanto , Antioxidantes/farmacologia , Tragacanto/química , Aminoácidos/metabolismo , Anti-Infecciosos/farmacologia , Antibacterianos/farmacologia
3.
Int J Biol Macromol ; 253(Pt 8): 127502, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37863139

RESUMO

Micronutrient deficiencies, such as iron, folic acid, and vitamins C and D, are currently prevalent due to inadequate consumption of natural food sources, namely raw vegetables and fruits. This deficiency is compounded by the growing reliance on synthetic nutraceuticals and processed food, which exhibit poor absorbency within the gastrointestinal tract. Scientific studies consistently indicate that naturally prepared whole foods are superior in terms of nutrient absorption compared to processed and synthetic supplements. To address this issue, we utilized FDA-approved tragacanth gum (TG) in the synthesis of nano-nutraceuticals by encapsulating beetroot juice and ball-milled sweet basil (Ocimum basilicum). TG, in its micro or macro form, possesses the remarkable ability to form hydrogels capable of absorbing water up to 50 times its weight. However, the hydrogel-forming property diminishes when TG is reduced to the nanoscale. We effectively exploited these properties to facilitate the synthesis of nano-nutraceuticals. The procedure involved encapsulating beetroot juice and sweet basil nanopowder using TG hydrogel, followed by freeze-drying. Subsequently, the freeze-dried encapsulated TG composite was subjected to ball-milling to achieve the desired nano-nutraceuticals. These nano-nutraceuticals naturally contain essential nutrients such as iron, folic acid, ascorbic acid, chlorophyll, niacin, and sugars, without the need for chemical processing or preservatives.


Assuntos
Ocimum basilicum , Oligoelementos , Tragacanto , Micronutrientes , Tragacanto/química , Suplementos Nutricionais , Antioxidantes , Ferro , Hidrogéis
4.
Int J Biol Macromol ; 249: 126041, 2023 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-37516227

RESUMO

As pivotal role of scaffold in tissue engineering (TE), the aim of present study was to design and development of extracellular matrix (ECM)-mimetic electrically conductive nanofibrous scaffolds composed of polyaniline-grafted tragacanth gum (TG-g-PANI) and poly(vinyl alcohol) (PVA) with different PANI content for skin tissue engineering (STE) application. The fabricated scaffolds were preliminary evaluated in terms of some physicochemical and biological properties. Cytocompatibility and cells proliferation properties of the scaffolds were examined with the well-known MTT assay, and it was found that the developed scaffolds have proper cytocompatibilities and can enhances the mouse fibroblast L929 cells adhesion as well as proliferation, which confirm their potential for STE applications. Hemocompatibility assay revealed that the hemolysis rate of the fabricated scaffolds were <2 % even at a relatively high concentration (200 µgmL-1) of samples, therefore, these scaffolds can be considered as safe. Human serum albumin (HSA) protein adsorption capacities of the fabricated scaffolds were quantified as 42 and 49 µgmg-1 that represent suitable values for a successful TE. Overall, the fabricated scaffold with 20 wt% of TG-g-PANI showed higher potential in both physicochemical and biological features than scaffold with 30 wt% of mentioned copolymer for STE application.


Assuntos
Nanofibras , Tragacanto , Camundongos , Animais , Humanos , Engenharia Tecidual , Álcool de Polivinil/química , Tecidos Suporte/química , Tragacanto/química , Nanofibras/química , Poliésteres/química , Matriz Extracelular
5.
Int J Biol Macromol ; 241: 124343, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37054856

RESUMO

Tragacanth is an abundant natural gum extracted from some plants and is dried for use in various applications from industry to biomedicines. It is a cost-effective and easily accessible polysaccharide with desirable biocompatibility and biodegradability, drawing much attention for use in new biomedical applications such as wound healing and tissue engineering. Moreover, this anionic polysaccharide with a highly branched structure has been used as an emulsifier and thickening agent in pharmaceutical applications. In addition, this gum has been introduced as an appealing biomaterial for producing engineering tools in drug delivery. Furthermore, the biological properties of tragacanth gum have made it a favorable biomaterial in cell therapies, and tissue engineering. This review aims to discuss the recent studies on this natural gum as a potential carrier for different drugs and cells.


Assuntos
Tragacanto , Tragacanto/química , Materiais Biocompatíveis/química , Sistemas de Liberação de Medicamentos , Excipientes , Terapia Baseada em Transplante de Células e Tecidos
6.
Int J Biol Macromol ; 237: 124250, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36996955

RESUMO

This study aimed to investigate the segregative interaction of gelatin (G) and tragacanth gum (TG) and the stabilization of their water-in-water (W/W) emulsion by G-TG complex coacervate particles. Segregation was studied at different pHs, ionic strengths and biopolymer concentrations. Results showed that incompatibility was affected by increasing the biopolymer concentrations. So, three reigns were demonstrated in the phase diagram of the salt-free samples. NaCl significantly changed the phase behavior via enhancement of self-association of polysaccharide and changing solvent quality due to the charge screening effect of ions. The W/W emulsion prepared from these two biopolymers and stabilized with G-TG complex particles was stable for at least one week. The microgel particles improved emulsion stability by adsorption to the interface and creating a physical barrier. A fibrous and network-like structure of the G-TG microgels was observed by scanning electron microscopy images suggesting the Mickering emulsion stabilization mechanism. It was confirmed that the bridging flocculation between the microgel polymers led to phase separation after the stability period. Biopolymer incompatibility investigation is a useful tool to obtain beneficial knowledge for preparation new food formulation, especially no contain oil emulsions for low- calorie diets.


Assuntos
Microgéis , Tragacanto , Emulsões/química , Gelatina , Tragacanto/química , Água/química
7.
Carbohydr Polym ; 305: 120548, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36737197

RESUMO

Nanocomposite hydrogels based on tyramine conjugated gum tragacanth, poly (vinyl alcohol) (PVA), and halloysite nanotubes (HNTs) were prepared by electron beam irradiation and characterized. The FTIR, 1H NMR, and TGA results confirmed the chemical incorporation of HNTs into gum tragacanth. Gel content and swelling of hydrogels decreased with HNTs loading up to 20 % wt. The mechanical strength of hydrogels increased by increasing HNTs content up to 10 % with 371 kPa fracture stress at 0.95 fracture strain, compared to 312 kPa stress at 0.79 strain for gum tragacanth/PVA hydrogel. Hydrogel's biocompatibility and osteogenic activity were tested by seeding rabbit bone marrow mesenchymal stem cells. The cell viability was >85 % after 7 days of culture. In vitro secretion of ALP and calcium deposition on hydrogels in alizarin red assay after 21 days of culture indicated hydrogel potential for bone tissue engineering.


Assuntos
Engenharia Tecidual , Tragacanto , Animais , Coelhos , Argila , Elétrons , Hidrogéis/farmacologia , Hidrogéis/química , Engenharia Tecidual/métodos , Tragacanto/química , Álcool de Polivinil/química
8.
J Biomater Appl ; 37(8): 1409-1422, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36045495

RESUMO

Management of uncontrolled bleeding due to traumatic injuries occurring in battlefields and road traffic accidents is a major healthcare concern, especially in developing countries like India. Since natural coagulation mechanism alone is insufficient to achieve haemostasis quickly in such cases, application of an external haemostatic product is generally required to accelerate the coagulation process. We had recently reported preliminary comparison of four natural absorbent gums, which indicated towards haemostatic potential of gum tragacanth (GT) and xanthan gum (XG). Present study involves fabrication of haemostatic dressings incorporated with different concentrations of GT or XG, along with ciprofloxacin (a broad-spectrum antibiotic) and other excipients over woven cotton gauze. Prepared gauzes were investigated for physico-chemical characteristics, in-vitro blood interaction studies, antibacterial effect and in-vivo haemostatic efficacy in Sprague Dawley rats using two bleeding models. Acute dermal toxicity studies were also carried out as per OECD guidelines. SEM studies showed that gauzes coated with XG had thin, uniform layer of coating, while in case of GT; coating was comparatively rough with insoluble particles of GT adhering over gauze surface, forming voids on the fibers. Coated gauzes exhibited optimum mechanical properties in terms of tensile strength and percent extension at break. GT coated dressings showed good fluid uptake and retention ability in-vitro. Test gauzes were non-hemolytic in nature, did not elicit any dermal toxicity on animals' skin and had the ability to protect against E. coli infection. In-vivo efficacy studies in rat femoral artery and liver laceration bleeding models indicated that gauzes coated with 4% GT were able to clot blood in least time (36.67 ± 3.33s and 40 ± 2.58s respectively) as compared to other gum combinations and commercially available dressing 'Surgispon® (103.3 ± 4.22s and 85 ± 5.62s respectively). Results of this study validate our initial findings of the potential of gum tragacanth to be developed into a suitable haemostatic product.


Assuntos
Hemostáticos , Tragacanto , Ratos , Animais , Tragacanto/química , Escherichia coli , Ratos Sprague-Dawley , Hemostáticos/farmacologia , Hemostáticos/uso terapêutico , Hemorragia/tratamento farmacológico , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Antibacterianos/química , Bandagens
9.
Int J Biol Macromol ; 226: 1411-1425, 2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36442552

RESUMO

Hybridization of nanomaterials (NMs) with natural polymers is one of the best techniques to promote their exciting properties. In this way, the main objective of this work was to investigate the efficiency of decoration of the graphene oxide (GO) nano-sheets with tragacanth gum (TG) polysaccharide. To aim this, different approaches were used (with and without ultrasonic treatment) and various tests (XRD, FTIR, Raman, UV-Vis, DLS, Zeta potential, contact angle, AFM, FE-SEM, TEM, and MTT assay) were conducted. Test results indicated that the nano-hybrids were successfully synthesized. Furthermore, our findings represented that, the TG hybridized GO (TG-GO) appreciably enhanced the biocompatibility of GO. Moreover, it was demonstrated that the ultrasonic treatment of TG solution put a remarkable impact on the microstructure, wettability, and also surface charge characteristic of fabricated nano-hybrids and consequently improved the biocompatibility against L929-fibroblast cells.


Assuntos
Grafite , Nanoestruturas , Tragacanto , Tragacanto/química , Grafite/farmacologia , Grafite/química , Polímeros
10.
Biofouling ; 38(10): 965-983, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36519335

RESUMO

Biomaterial associated bacterial infections are indomitable to treatment due to the rise in antibiotic resistant strains, thereby triggering the need for new antibacterial agents. Herein, composite bactericidal hydrogels were formulated by incorporating silver nanotriangles (AgNTs) inside a hybrid polymer network of Gum Tragacanth/Sodium Alginate (GT/SA) hydrogels. Physico-chemical examination revealed robust mechanical strength, appreciable porosity and desirable in vitro enzymatic biodegradation of composite hydrogels. The antibacterial activity of AgNT-hydrogel was tested against planktonic and biofilm-forming Gram-negative (Escherichia coli and Pseudomonas aeruginosa) and Gram-positive (Staphylococcus aureus) bacteria. For all the strains, AgNT-hydrogel showed a dose-dependent decrease in bacterial growth. The addition of AgNT-hydrogels (40-80 mg ml-1) caused 87% inhibition of planktonic biomass and up to 74% reduction in biofilm formation. Overall, this study proposes a promising approach for designing antibacterial composite hydrogels to mitigate various forms of bacterial infection.


Assuntos
Infecções Estafilocócicas , Tragacanto , Humanos , Prata/farmacologia , Prata/química , Hidrogéis/farmacologia , Hidrogéis/química , Tragacanto/química , Alginatos/farmacologia , Biofilmes , Bactérias , Escherichia coli , Antibacterianos/farmacologia , Antibacterianos/química
11.
Acta Chim Slov ; 69(3): 714-721, 2022 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-36196822

RESUMO

A novel superparamagnetic nano-composite of Fe3O4@SiO2 coated by tragacanth gum (TG) as a natural product has been prepared. The obtained SiO2@Fe3O4@TG nanoparticles were characterized by Fourier transform infrared spectroscopy, energy dispersive X-ray analysis, scanning electron microscopy and dynamic light scattering analyzer. The magnetic nano-composite was applied for the loading and delivery of metformin, an oral diabetes medicine. The conditions for the loading of the drug were optimized by a central composite design optimization method. The maximum loading efficiency of the sorbent for metformin was obtained at pH 7 and its maximum in-vitro release was achieved at pH 1.6, using a phosphate-buffered saline medium. The loading capacity of the sorbent was dependent on the initial metformin concentration and exceeded to 19.6 mg/g in a 200 mg/L solution. A study of the adsorption isotherms for the drug indicated the best fitting into the Langmuir and Freundlich isotherms at the low and high metformin concentrations, respectively. The results indicated that the prepared Fe3O4@SiO2@TG adsorbent, as a non-toxic and low-cost sorbent, was quite appropriate for drug delivery applications.


Assuntos
Metformina , Nanopartículas , Tragacanto , Adsorção , Compostos Férricos , Nanopartículas Magnéticas de Óxido de Ferro , Fosfatos , Dióxido de Silício/química , Espectroscopia de Infravermelho com Transformada de Fourier , Tragacanto/química
12.
Nanoscale ; 14(32): 11635-11654, 2022 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-35904404

RESUMO

In this report, biogenic, crystalline (∼60.5 ± 2%) bowknot structured silica nanoparticles (BSNPs) of length ∼ 274 ± 7 nm and width ∼ 36 ± 2 nm were isolated from invasive species viz. Lantana camara. These were then chemically modified using nitrogen containing moieties viz. APTES and CTAB. These modified BSNPs were then used as electrostatic cross-linking agents for the formation of tragacanth gum (TG) hydrogels. The cytocompatible CTAB@BSNP-TG hydrogels documented ∼10-12 fold enhancement in anti-bacterial activity against Staphylococcus aureus and Pseudomonas aeruginosa when compared with TG hydrogels. Disruption of the bacterial membrane by ROS generation and protein leakage were responsible for anti-bacterial activity. A cell migration assay suggested that CTAB@BSNP-TG augmented the cell proliferation of NIH-3T3 cells compared to other TG hydrogels. The present study will pave the path for the development of organic-inorganic hybrid nanocomposite-based hydrogels for anti-bacterial and cell migration applications.


Assuntos
Nanopartículas , Tragacanto , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Cetrimônio , Hidrogéis/química , Hidrogéis/farmacologia , Camundongos , Dióxido de Silício , Tragacanto/química
13.
Int J Biol Macromol ; 207: 193-204, 2022 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-35248610

RESUMO

This study focuses on polyester fabric modification to produce environmentally-friendly multifunctional fabrics for varied applications. The nanoparticles of iron oxide were achieved from ferrous sulfate solution under alkaline conditions and applied to Tragacanth gum to form an efficient layer on the polyester surface. The synthesis of Fe3O4 nanoparticles with a crystal size of 12 nm was approved in the XRD spectra and iron oxide/Tragacanth gum nanocomposites with an agglomerated size of about 62 nm were confirmed by the SEM and EDX techniques. The formation of hydroxyl and iron oxide bands was observed in the FTIR and XPS patterns. The superparamagnetic behavior of treated samples exhibited by VSM with a magnetic saturation of 0.86 emu/g. The products showed an antibacterial activity (95 and 91%) toward Gram-positive and -negative bacteria. The absorbance intensity of methylene blue decreased from 2.6 to 1.6 by the treated sample. The synthesized nanoparticles on the treated surface indicated a lower release of iron ions and cell toxicity. The rate of cell duplication increased under a magnetic field with 60 Hz and 0.5 mT for 20 min/day. The product color changed from white to a brownish hue and the wetting capacity and thermal ability increased.


Assuntos
Nanopartículas , Tragacanto , Compostos Férricos , Nanopartículas/química , Poliésteres/química , Têxteis , Tragacanto/química
14.
Crit Rev Food Sci Nutr ; 62(14): 3913-3929, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33427482

RESUMO

Naturally occurring plant-based gums and their engineered bio-nanostructures have gained an immense essence of excellence in several industrial, biotechnological, and biomedical sectors of the modern world. Gums derived from bio-renewable resources that follow green chemistry principles are considered green macromolecules with unique structural and functional attributes. For instance, gum mostly obtained as exudates are bio-renewable, bio-degradable, bio-compatible, sustainable, overall cost-effective, and nontoxic. Gum exudates also offer tunable attributes that play a crucial role in engineering bio-nanostructures of interest for several bio- and non-bio applications, e.g., food-related items, therapeutic molecules, sustained and controlled delivery cues, bio-sensing constructs, and so on. With particular reference to plant gum exudates, this review focuses on applied perspectives of various gums, i.e., gum Arabic, gum albizzia, gum karaya, gum tragacanth, and gum kondagogu. After a brief introduction with problem statement and opportunities, structural and physicochemical attributes of plant-based natural gums are presented. Following that, considerable stress is given to green synthesis and stabilization of gum-based bio-nanostructures. The final part of the review focuses on the bio- and non-bio related applications of various types of gums polysaccharides-oriented bio-nanostructures.


Assuntos
Nanoestruturas , Tragacanto , Goma Arábica/química , Gomas Vegetais , Polissacarídeos , Tragacanto/química
15.
Int J Biol Macromol ; 192: 869-882, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34634330

RESUMO

Injectable hydrogels have been known as promising materials for the regeneration of irregular shape tissue defects. In this study, novel thermosensitive methylcellulose (MC) hydrogels containing bassorin (Ba) and halloysite nanotubes (HNTs) have been developed for application in bone tissue engineering. Bassorin isolated from gum tragacanth (GT) with the concentration of 0.25-1.5 w/v% was blended with MC. The best MC/Ba gel (containing 0.5% bassorin) was chosen based on the results of injectability and rheological tests. HNTs (1-7%) were added to this formulation and tested for the physicochemical, mechanical, rheological, degradation, swelling, and biological properties. In vitro biological evaluations including cell proliferation (by MTT assay), cell attachment (by SEM), osteogenic activity (by Alizarin Red staining and alkaline phosphatase assay), and osteogenic gene expression (by quantitative real-time polymerase chain reaction) were done using MG-63 cells. Results showed that bassorin led to the increased gel-forming ability (at a lower temperature) and mechanical properties of MC hydrogel. The presence of HNTs and bassorin affected the degradation rate and swelling degree of MC-based hydrogel. Results showed significant enhancement in cell proliferation, differentiation, and mineralization, as well as higher bone-specific gene expression of the cell on bassorin and HNTs incorporated MC compared to pure MC hydrogel.


Assuntos
Regeneração Óssea , Fenômenos Químicos , Hidrogéis/química , Metilcelulose/química , Nanotubos/química , Tragacanto/química , Diferenciação Celular , Sobrevivência Celular , Fenômenos Mecânicos , Nanotubos/ultraestrutura , Porosidade , Reologia , Solubilidade , Análise Espectral , Engenharia Tecidual , Tecidos Suporte
16.
Int J Biol Macromol ; 184: 909-925, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-34144070

RESUMO

Microwave assisted homogeneous heating, selectivity in radical formation, and the faster polymerization facilitate the synthesis, structures, properties, and the higher branching associated stability of multifunctional multipolymers. Thus, the optimum gum tragacanth (GMTR)-grafted pentapolymer hydrogel/ HG2 was synthesized from three monomers, i.e., cis-butenedioic acid (cBDA), N-hydroxymethylacryalamide (NHMAm), and 2-(methacryloyloxy)ethanol (MAOE), and in situ generated 2-(3-((hydroxymethyl)amino)-3-oxopropoxy)ethyl-2-methylbutanoate (CM1) and 2-hydroxyethyl 3-(N-(hydroxymethyl)-2-methylbutanamido)-2-methylpropanoate (CM2) comonomers through microwave assisted facile polymerization in aqueous medium. Here, twenty-one GMTR-grafted-[cBDA-co-CM1-co-NHMAm-co-CM2-co-MAOE/ HG1] hydrogels were prepared by using variable amounts of synthesis parameters, of which the optimum HG2 was chosen for the scale-up repetitive As(III)-exclusion. RSM was used to measure the optimum power-temperature-time of microwave irradiation. The structures of HG1, HG2, and As(III)-adsorbed HG2/ As(III)-HG2, in situ anchored comonomers, GMTR-grafting, reusability, thermostability, and surface phenomena were comprehended by XPS, NMR, UV-vis, FTIR, TG, XRD, DLS, and SEM analyses; pHPZC; network parameters; and thermodynamic variables. The geometries, electronic structures, and variable coordinations of As(III) with HG2 were investigated through DFT studies of HG2 and As(OH)3-HG2. The highest exclusion efficiency of 25 mg HG2 within 5-100 mg L-1 As(III) and at 298 K was 192.91 mg g-1, which was significantly higher than that of HG1.


Assuntos
Substâncias Macromoleculares/síntese química , Tragacanto/química , Adsorção , Teoria da Densidade Funcional , Hidrogéis , Concentração de Íons de Hidrogênio , Substâncias Macromoleculares/química , Micro-Ondas , Estrutura Molecular , Polimerização , Temperatura
17.
Molecules ; 26(6)2021 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-33802011

RESUMO

The use of naturally occurring materials in biomedicine has been increasingly attracting the researchers' interest and, in this regard, gum tragacanth (GT) is recently showing great promise as a therapeutic substance in tissue engineering and regenerative medicine. As a polysaccharide, GT can be easily extracted from the stems and branches of various species of Astragalus. This anionic polymer is known to be a biodegradable, non-allergenic, non-toxic, and non-carcinogenic material. The stability against microbial, heat and acid degradation has made GT an attractive material not only in industrial settings (e.g., food packaging) but also in biomedical approaches (e.g., drug delivery). Over time, GT has been shown to be a useful reagent in the formation and stabilization of metal nanoparticles in the context of green chemistry. With the advent of tissue engineering, GT has also been utilized for the fabrication of three-dimensional (3D) scaffolds applied for both hard and soft tissue healing strategies. However, more research is needed for defining GT applicability in the future of biomedical engineering. On this object, the present review aims to provide a state-of-the-art overview of GT in biomedicine and tries to open new horizons in the field based on its inherent characteristics.


Assuntos
Tragacanto/química , Tragacanto/metabolismo , Tragacanto/farmacologia , Antibacterianos/química , Astragalus gummifer/metabolismo , Materiais Biocompatíveis/química , Sistemas de Liberação de Medicamentos/métodos , Embalagem de Alimentos/métodos , Nanofibras/química , Poliésteres/química , Medicina Regenerativa/métodos , Engenharia Tecidual/métodos , Tecidos Suporte/química , Cicatrização/efeitos dos fármacos
18.
J Biomed Mater Res A ; 109(11): 2164-2172, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-33866680

RESUMO

Oral administration of insulin is one of the most challenging topics within this area, because insulin is degraded in stomach before it enters the bloodstream. In this study, for the first time, a nano-carrier for controlled and targeted oral delivery of insulin was developed using de-esterified Tragacanth and chitosan. The fabricated nanoparticles were synthesized using coacervation technique and their properties were optimized using response surface methodology. The effect of experimental variables on the particle size and loading efficiency was examined. In addition, the interactions between components were analyzed using Fourier transform infrared. The thermal stability of nanoparticles was studied by thermal gravimetric analysis. The insulin loading efficiency was measured and in vitro release profile and ex vivo insulin permeability was determined. Optimized nanoparticles showed spherical shape with a size less than 200 nm and zeta potential of +17 mV. Owing to their nanoscale dimensions and mucoadhesiveness, nanoparticles were synthesized using medium molecular weight of Chitosan. The insulin loading efficacy for the system was 6.4%, released under simulated gastrointestinal conditions in a pH-dependent manner. Based on all of the obtained results, it can be concluded that these nanoparticles can potentially be utilized as a carrier for the oral insulin delivery.


Assuntos
Quitosana , Portadores de Fármacos , Insulina , Nanocompostos , Tragacanto , Administração Oral , Animais , Quitosana/química , Quitosana/farmacologia , Portadores de Fármacos/química , Portadores de Fármacos/farmacologia , Humanos , Insulina/química , Insulina/farmacocinética , Insulina/farmacologia , Masculino , Nanocompostos/química , Nanocompostos/uso terapêutico , Ratos , Ratos Wistar , Tragacanto/química , Tragacanto/farmacologia
19.
Food Chem ; 354: 129492, 2021 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-33756322

RESUMO

Gelatin and tragacanth were employed to fabricate antimicrobial nanocomposites with 1, 3, and 5% zinc oxide nanoparticles (ZnO-NPs). FT-IR and XRD proved new chemical interactions among GEL/TGC/ZnO-NPs and higher crystallinity of nanocomposites, respectively. DSC showed a significant increase in melting point temperature (Tm) from ~ 90 to ~ 93-101 °C after adding 1-5% ZnO-NPs. Ultimate tensile strength (UTS) was remarkably increased to 31.21, 34.57, and 35.06 MPa, as well as Young's Modulus to 287.44, 335.47, and 367.04 MPa after incorporating 1, 3, and 5% ZnO-NPs. The ZnO-NPs dose-dependently reduced the water vapor permeability (WVP) of the films. FE-SEM analysis from surface and cross-section illustrated the compact and homogenous structure of the nanocomposites even up to 5% ZnO-NPs. The ZnO-NPs-containing nanocomposites had a good antimicrobial activity (~10-20 mm) against both Staphylococcus aureus and Escherichia coli. Generally, the results indicated that the prepared nanocomposite films are promising antimicrobial bio-materials for food packaging.


Assuntos
Anti-Infecciosos/química , Embalagem de Alimentos/métodos , Gelatina/química , Nanocompostos/química , Tragacanto/química , Óxido de Zinco/química , Anti-Infecciosos/farmacologia , Varredura Diferencial de Calorimetria , Cor , Escherichia coli/efeitos dos fármacos , Nanopartículas Metálicas/química , Nanocompostos/toxicidade , Permeabilidade/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Resistência à Tração , Água/química
20.
Int J Biol Macromol ; 179: 101-115, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33621571

RESUMO

Angiogenic-osteogenic cell encapsulation system is a technical need for human mesenchymal stem cell (hMSC)-based bone tissue engineering (BTE). Here, we have developed a highly efficient hMSC encapsulation system by incorporating bivalent cobalt doped nano-hydroxyapatite (HAN) and gum tragacanth (GT) as angiogenic-osteogenic components into the calcium alginate (CA) beads. Physico-chemical characterizations revealed that the swelling and degradation of HAN incorporated CA-GT beads (GT-HAN) were 1.34 folds and 2 folds higher than calcium alginate (CA) beads. Furthermore, the diffusion coefficient of solute molecule was found 2.5-fold higher in GT-HAN with respect to CA bead. It is observed that GT-HAN supports the long-term viability of encapsulated hMSC and causes 50% less production of reactive oxygen species (ROS) in comparison to CA beads. The expression of osteogenic differentiation markers was found 1.5-2.5 folds higher in the case of GT-HAN in comparison to CA. A similar trend was observed for hypoxia inducible factor 1 alpha (HIF-1α) and vascular endothelial growth factor (VEGF). The soluble secretome from hMSC encapsulated in the GT-HAN induced proliferation of endothelial cells and supported tube formation (2.5-fold higher than CA beads). These results corroborated that GT-HAN could be used as an angiogenic-osteogenic cell encapsulation matrix for hMSC encapsulation and BTE application.


Assuntos
Alginatos/química , Osso e Ossos/metabolismo , Células Imobilizadas/metabolismo , Cobalto/química , Durapatita/química , Células-Tronco Mesenquimais/metabolismo , Neovascularização Fisiológica , Osteogênese , Engenharia Tecidual , Tragacanto/química , Humanos
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