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1.
Int J Biol Macromol ; : 131666, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38636755

RESUMO

Natural Rubber Latex (NRL) has shown to be a promising biomaterial for use as a drug delivery system to release various bioactive compounds. It is cost-effective, easy to handle, biocompatible, and exhibits pro-angiogenic and pro-healing properties for both soft and hard tissues. NRL releases compounds following burst and sustained release kinetics, exhibiting first-order release kinetics. Moreover, its pore density can be adjusted for tailored kinetics profiles. In addition, biotechnological applications of NRL in amblyopia, smart mattresses, and neovaginoplasty have demonstrated success. This comprehensive review explores NRL's diverse applications in biotechnology and biomedicine, addressing challenges in translating research into clinical practice. Organized into eight sections, the review emphasizes NRL's potential in wound healing, drug delivery, and metallic nanoparticle synthesis. It also addresses the challenges in enhancing NRL's physical properties and discusses its interactions with the human immune system. Furthermore, examines NRL's potential in creating wearable medical devices and biosensors for neurological disorders. To fully explore NRL's potential in addressing important medical conditions, we emphasize throughout this review the importance of interdisciplinary research and collaboration. In conclusion, this review advances our understanding of NRL's role in biomedical and biotechnological applications, offering insights into its diverse applications and promising opportunities for future development.

2.
Lab Chip ; 24(8): 2358-2359, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38501991

RESUMO

Correction for 'Integrated biosensors for monitoring microphysiological systems' by Lei Mou et al., Lab Chip, 2022, 22, 3801-3816, https://doi.org/10.1039/D2LC00262K.

3.
Biomater Adv ; 157: 213754, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38211507

RESUMO

Chronic wounds pose significant health concerns. Current treatment options include natural compounds like natural rubber latex (NRL) from Hevea brasiliensis. NRL, particularly the F1 protein fraction, has demonstrated bioactivity, biocompatibility, and angiogenic effects. So far, there is no study comparing F1 protein with total NRL serum, and the necessity of downstream processing remains unknown. Here, we evaluated the angiogenic potential of F1 protein compared to total NRL serum and the need for downstream processing. For that, ion exchange chromatography (DEAE-Sepharose), antioxidant activity, physicochemical characterization, cell culture in McCoy fibroblasts, and wound healing in Balb-C mice were performed. Also, the evaluation of histology and collagen content and the levels of inflammatory mediators were quantified. McCoy fibroblast cell assay showed that F1 protein (0.01 %) and total NRL serum (0.01 %) significantly increased cell proliferation by 47.1 ± 11.3 % and 25.5 ± 2.5 %, respectively. However, the AA of F1 protein (78.9 ± 0.8 %) did not show a significant difference compared to NRL serum (77.0 ± 1.1 %). F1 protein and NRL serum were more effective in wound management in rodents. Histopathological analysis confirmed accelerated healing and advanced tissue repair. Similarly, the F1 protein (0.01 %) increased collagen, showing that this fraction can stimulate the synthesis of collagen by fibroblastic cells. Regarding cytokines production (IL-10, TNF-α, IFN-γ), F1 protein and NRL serum did not exert an impact on the synthesis of these cytokines. Furthermore, we did not observe statistically significant changes in dosages of enzymes (MPO and EPO) among the groups. Nevertheless, Nitric Oxide dosage was reduced drastically when the F1 protein (0.01 %) protein was applied topically. These findings contribute to the understanding of F1 protein and NRL serum properties and provide insights into cost-effectiveness and practical applications in medicine and biotechnology. Therefore, further research is needed to assess the economic feasibility of downstream processing for NRL-based herbal medicine derived from Hevea brasiliensis.


Assuntos
Hevea , Borracha , Animais , Camundongos , Látex , Hevea/química , Cicatrização , Colágeno , Citocinas
4.
J Control Release ; 365: 744-758, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38072085

RESUMO

Amphotericin B (AmB) is the gold standard for antifungal drugs. However, AmB systemic administration is restricted because of its side effects. Here, we report AmB loaded in natural rubber latex (NRL), a sustained delivery system with low toxicity, which stimulates angiogenesis, cell adhesion and accelerates wound healing. Physicochemical characterizations showed that AmB did not bind chemically to the polymeric matrix. Electronic and topographical images showed small crystalline aggregates from AmB crystals on the polymer surface. About 56.6% of AmB was released by the NRL in 120 h. However, 33.6% of this antifungal was delivered in the first 24 h due to the presence of AmB on the polymer surface. The biomaterial's excellent hemo- and cytocompatibility with erythrocytes and human dermal fibroblasts (HDF) confirmed its safety for dermal wound application. Antifungal assay against Candida albicans showed that AmB-NRL presented a dose-dependent behavior with an inhibition halo of 30.0 ± 1.0 mm. Galleria mellonella was employed as an in vivo model for C. albicans infection. Survival rates of 60% were observed following the injection of AmB (0.5 mg.mL-1) in G. mellonella larvae infected by C. albicans. Likewise, AmB-NRL (0.5 mg.mL-1) presented survival rates of 40%, inferring antifungal activity against fungus. Thus, NRL adequately acts as an AmB-sustained release matrix, which is an exciting approach, since this antifungal is toxic at high concentrations. Our findings suggest that AmB-NRL is an efficient, safe, and reasonably priced ($0.15) dressing for the treatment of cutaneous fungal infections.


Assuntos
Candidíase , Infecção dos Ferimentos , Humanos , Anfotericina B , Antifúngicos/química , Bandagens , Candida albicans , Candidíase/tratamento farmacológico , Látex , Testes de Sensibilidade Microbiana , Infecção dos Ferimentos/tratamento farmacológico
5.
Biomater Adv ; 157: 213739, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38154400

RESUMO

Advances and the discovery of new biomaterials have opened new frontiers in regenerative medicine. These biomaterials play a key role in current medicine by improving the life quality or even saving the lives of millions of people. Since the 2000s, Natural Rubber Latex (NRL) has been employed as wound dressings, mechanical barrier for Guided Bone Regeneration (GBR), matrix for drug delivery, and grafting. NRL is a natural polymer that can stimulate cell proliferation, neoangiogenesis, and extracellular matrix (ECM) formation. Furthermore, it is well established that proteins and other biologically active molecules present in the Natural Latex Serum (NLS) are responsible for the biological properties of NRL. NLS can be obtained from NRL by three main methods, namely (i) Centrifugation (fractionation of NRL in distinct fractions), (ii) Coagulation and sedimentation (coagulating NRL to separate the NLS from rubber particles), and (iii) Alternative extraction process (elution from NRL membrane). In this review, the chemical composition, physicochemical properties, toxicity, and other biological information such as osteogenesis, vasculogenesis, adhesion, proliferation, antimicrobial behavior, and antitumoral activity of NLS, as well as some of its medical instruments and devices are discussed. The progress in NLS applications in the biomedical field, more specifically in cell cultures, alternative animals, regular animals, and clinical trials are also discussed. An overview of the challenges and future directions of the applications of NLS and its derivatives in tissue engineering for hard and soft tissue regeneration is also given.


Assuntos
Hipersensibilidade ao Látex , Látex , Animais , Humanos , Alérgenos , Proteínas , Materiais Biocompatíveis
6.
Macromol Biosci ; 23(12): e2300276, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37534566

RESUMO

Several microfabrication technologies have been used to engineer native-like skeletal muscle tissues. However, the successful development of muscle remains a significant challenge in the tissue engineering field. Muscle tissue engineering aims to combine muscle precursor cells aligned within a highly organized 3D structure and biological factors crucial to support cell differentiation and maturation into functional myotubes and myofibers. In this study, the use of 3D bioprinting is proposed for the fabrication of muscle tissues using gelatin methacryloyl (GelMA) incorporating sustained insulin-like growth factor-1 (IGF-1)-releasing microparticles and myoblast cells. This study hypothesizes that functional and mature myotubes will be obtained more efficiently using a bioink that can release IGF-1 sustainably for in vitro muscle engineering. Synthesized microfluidic-assisted polymeric microparticles demonstrate successful adsorption of IGF-1 and sustained release of IGF-1 at physiological pH for at least 21 days. Incorporating the IGF-1-releasing microparticles in the GelMA bioink assisted in promoting the alignment of myoblasts and differentiation into myotubes. Furthermore, the myotubes show spontaneous contraction in the muscle constructs bioprinted with IGF-1-releasing bioink. The proposed bioprinting strategy aims to improve the development of new therapies applied to the regeneration and maturation of muscle tissues.


Assuntos
Bioimpressão , Tecidos Suporte , Tecidos Suporte/química , Fator de Crescimento Insulin-Like I/farmacologia , Engenharia Tecidual , Músculo Esquelético/fisiologia , Fibras Musculares Esqueléticas , Hidrogéis/farmacologia , Hidrogéis/química , Gelatina/farmacologia , Gelatina/química , Impressão Tridimensional
7.
Int J Biol Macromol ; 249: 126016, 2023 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-37516224

RESUMO

Films and coatings manufactured with bio-based renewable materials, such as biopolymers and essential oils, could be a sustainable and eco-friendly alternative for protecting and preserving agricultural products. In this work, we developed films and coatings from pectin and chitosan to protect strawberries (Fragaria x ananassa Duch.) from spoilage and microbial contamination. We developed three coatings containing equal amounts of glycerol and Sicilian lemon essential oil (LEO) nanoemulsion. We identified seventeen chemicals from LEO by GC-MS chromatogram, including d-limonene, α-Pinene, ß-Pinene, and γ-Terpinene. The pectin and chitosan coatings were further characterized using different physicochemical, mechanical, and biological methods. The films demonstrated satisfactory results in strength and elongation at the perforation as fruit packaging. In addition, the coatings did not influence the weight and firmness of the strawberry pulps. We observed that 100 % essential oil was released in 1440 min resulting from the erosion process. Also, the oil preserved the chemical stability of the films. Antioxidant activity (AA), measured by Electron Paramagnetic Resonance (EPR), showed that the coatings loaded with 2 % LEO nanoemulsion (PC + oil) showed that almost 50 % of AA from LEO nanoemulsion was preserved. The chitosan and the pectin-chitosan coatings (PC + oil) inhibited filamentous fungi and yeast contaminations in strawberries for at least 14 days, showing a relationship between the AA and antimicrobial results.


Assuntos
Quitosana , Fragaria , Óleos Voláteis , Óleos Voláteis/farmacologia , Óleos Voláteis/química , Fragaria/microbiologia , Quitosana/química , Pectinas/farmacologia , Pectinas/química , Antioxidantes/farmacologia , Antioxidantes/química , Conservação de Alimentos/métodos
8.
Int J Biol Macromol ; 242(Pt 1): 124779, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37172697

RESUMO

Psoriasis is a disease that causes keratinocytes to proliferate ten times faster than normal, resulting in chronic inflammation and immune cell infiltration in the skin. Aloe vera (A. vera) creams have been used topically for treating psoriasis because they contain several antioxidant species; however, they have several limitations. Natural rubber latex (NRL) has been used as occlusive dressings to promote wound healing by stimulating cell proliferation, neoangiogenesis, and extracellular matrix formation. In this work, we developed a new A. vera-releasing NRL dressing by a solvent casting method to load A. vera into NRL. FTIR and rheological analyzes revealed no covalent interactions between A. vera and NRL in the dressing. We observed that 58.8 % of the loaded A. vera, present on the surface and inside the dressing, was released after 4 days. Biocompatibility and hemocompatibility were validated in vitro using human dermal fibroblasts and sheep blood, respectively. We observed that ~70 % of the free antioxidant properties of A. vera were preserved, and the total phenolic content was 2.31-fold higher than NRL alone. In summary, we combined the antipsoriatic properties of A. vera with the healing activity of NRL to generate a novel occlusive dressing that may be indicated for the management and/or treatment of psoriasis symptoms simply and economically.


Assuntos
Aloe , Psoríase , Humanos , Animais , Ovinos , Borracha , Látex , Antioxidantes/farmacologia , Psoríase/tratamento farmacológico , Bandagens
9.
Int J Biol Macromol ; 242(Pt 1): 124778, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37172704

RESUMO

Natural rubber latex (NRL) is a biopolymer widely used in biomedical applications. In this work, we propose an innovative cosmetic face mask, combining the NRL's biological properties with curcumin (CURC), which has a high level of antioxidant activity (AA) to provide anti-aging benefits. Chemical, mechanical and morphological characterizations were performed. The CURC released by the NRL was evaluated by permeation in Franz cells. Cytotoxicity and hemolytic activity assays were performed to assess safety. The findings showed that the biological properties of CURC were preserved after loading in the NRL. About 44.2 % of CURC was released within the first six hours, and in vitro permeation showed that 9.36 % ± 0.65 was permeated over 24h. CURC-NRL was associated with a metabolic activity higher than 70 % in 3 T3 fibroblasts, cell viability ≥95 % in human dermal fibroblasts, and a hemolytic rate ≤ 2.24 % after 24 h. Furthermore, CURC-NRL maintained the mechanical characteristics (range suitable) for human skin application. We observed that CURC-NRL preserved ~20 % antioxidant activity from curcumin-free after loading in the NRL. Our results suggest that CURC-NRL has the potential to be used in the cosmetics industry, and the experimental methodology utilized in this study can be applied to different kinds of face masks.


Assuntos
Curcumina , Borracha , Humanos , Antioxidantes/farmacologia , Máscaras , Curcumina/farmacologia , Curcumina/química , Envelhecimento
10.
Lab Chip ; 22(20): 3801-3816, 2022 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-36074812

RESUMO

Microphysiological systems (MPSs), also known as organ-on-a-chip models, aim to recapitulate the functional components of human tissues or organs in vitro. Over the last decade, with the advances in biomaterials, 3D bioprinting, and microfluidics, numerous MPSs have emerged with applications to study diseased and healthy tissue models. Various organs have been modeled using MPS technology, such as the heart, liver, lung, and blood-brain barrier. An important aspect of in vitro modeling is the accurate phenotypical and functional characterization of the modeled organ. However, most conventional characterization methods are invasive and destructive and do not allow continuous monitoring of the cells in culture. On the other hand, microfluidic biosensors enable in-line, real-time sensing of target molecules with an excellent limit of detection and in a non-invasive manner, thereby effectively overcoming the limitation of the traditional techniques. Consequently, microfluidic biosensors have been increasingly integrated into MPSs and used for in-line target detection. This review discusses the state-of-the-art microfluidic biosensors by providing specific examples, detailing their main advantages in monitoring MPSs, and highlighting current developments in this field. Finally, we describe the remaining challenges and potential future developments to advance the current state-of-the-art in integrated microfluidic biosensors.


Assuntos
Técnicas Biossensoriais , Microfluídica , Materiais Biocompatíveis , Técnicas Biossensoriais/métodos , Humanos , Dispositivos Lab-On-A-Chip , Fígado , Microfluídica/métodos
11.
Small ; 18(39): e2201401, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35978444

RESUMO

The human brain and central nervous system (CNS) present unique challenges in drug development for neurological diseases. One major obstacle is the blood-brain barrier (BBB), which hampers the effective delivery of therapeutic molecules into the brain while protecting it from blood-born neurotoxic substances and maintaining CNS homeostasis. For BBB research, traditional in vitro models rely upon Petri dishes or Transwell systems. However, these static models lack essential microenvironmental factors such as shear stress and proper cell-cell interactions. To this end, organ-on-a-chip (OoC) technology has emerged as a new in vitro modeling approach to better recapitulate the highly dynamic in vivo human brain microenvironment so-called the neural vascular unit (NVU). Such BBB-on-a-chip models have made substantial progress over the last decade, and concurrently there has been increasing interest in modeling various neurological diseases such as Alzheimer's disease and Parkinson's disease using OoC technology. In addition, with recent advances in other scientific technologies, several new opportunities to improve the BBB-on-a-chip platform via multidisciplinary approaches are available. In this review, an overview of the NVU and OoC technology is provided, recent progress and applications of BBB-on-a-chip for personalized medicine and drug discovery are discussed, and current challenges and future directions are delineated.


Assuntos
Doença de Alzheimer , Barreira Hematoencefálica , Transporte Biológico , Encéfalo , Humanos , Dispositivos Lab-On-A-Chip
12.
Int J Biol Macromol ; 211: 568-579, 2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35533848

RESUMO

Gold nanoparticles (AuNPs) have shown interesting properties and specific biofunctions, providing benefits and new opportunities for controlled release systems. In this research, we demonstrated the use of natural rubber latex (NRL) from Hevea brasiliensis as a carrier of AuNPs and the antibiotic metronidazole (MET). We prepared AuNP-MET-NRL and characterized by physicochemical, biological and in vitro release assays. The effect of AuNPs on MET release was evaluated using UV-Vis and Laser-Induced Breakdown Spectroscopy (LIBS) techniques. AuNPs synthesized by Turkevich and Frens method resulted in a spherical shape with diameters of 34.8 ± 5.5 nm. We verified that there was no emergence or disappearance of new vibrational bands. Qualitatively and quantitatively, we showed that the MET crystals dispersed throughout the NRL. The Young's modulus and elongation values at dressing rupture were in the range appropriate for human skin application. 64.70% of the AuNP-MET complex was released within 100 h, exhibiting a second-order exponential release profile. The LIBS technique allowed monitoring of the AuNP release, indicating the Au emission peak reduction at 267.57 nm over time. Moreover, the dressing displayed an excellent hemocompatibility and fibroblast cell viability. These results demonstrated that the AuNP-MET-NRL wound dressing is a promising approach for dermal applications.


Assuntos
Ouro , Látex , Nanopartículas Metálicas , Metronidazol , Bandagens , Ouro/química , Humanos , Látex/química , Nanopartículas Metálicas/química , Metronidazol/farmacologia , Borracha/química
13.
J Biomater Sci Polym Ed ; 33(6): 705-726, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34927570

RESUMO

Natural latex serum (NLS) is one of the natural rubber latex fractions from Hevea brasiliensis tree, which is formed by centrifuged serum and is composed of proteins, acids, nucleotides, salts and carbohydrates. The proteins present in NLS have demonstrated several interesting biological properties, including angiogenic, healing, osteogenic, anti-inflammatory, antimicrobial, in addition to inducing neovascularization, bone formation and osseointegration. Thus, we proposed to characterize NLS by physicochemical techniques and to investigate the biocompatibility by toxicological assays and safety test in Galleria mellonella. Infrared spectrum showed vibrational bands characteristic of amide I, II and III that are linked to the protein content, which was confirmed by the High Performance Liquid Chromatography profile and by the Electrophoresis analysis. This material did not exhibit hemolytic (rate <0.5%) and cytotoxic effects (viability >70%) and was able to enhance the proliferation of fibroblasts (>600%) after 3 days. The pronounced proliferative effect observed in fibroblast cells can be explained by the presence of the fibroblast growth factor (FGF) like protein revealed by the Western blot test. Moreover, NLS did not provoke toxic effects (survival ∼ 80%) on the G. mellonella model, indicating that it is a biocompatible and safe material.


Assuntos
Hevea , Látex , Hevea/química , Látex/química , Proteínas de Plantas/metabolismo , Proteínas , Cicatrização
14.
Food Chem ; 373(Pt B): 131476, 2022 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-34731815

RESUMO

Soybean and its derivatives are rich sources of nutrients and bioactive compounds with antioxidant properties, however, the wastes with high nutritional value are discarded by the industry. This study aimed to evaluate centesimal composition, microbial safety and antioxidant activity of soybean processing wastes (okara and okara flour) and soymilk. High fiber, carbohydrate, energy and lipids contents were found. Antioxidant activity by spectrophotometric and Electron Paramagnetic Resonance assays showed values for soybean (72.4% and 83.5%), okara (9.6% and 7.7%), okara flour (30.7% and 11.5%) and soymilk (28.4% and 36.5%). The total phenolic content was an average of 3.33 mg of gallic acid equivalent.g-1. Infrared spectra revealed no significant changes in the absorption bands, guaranteeing non-alteration in the compounds composition after processing. Microbiological assays indicated that soybean derivatives are safe for consumption. These results reinforce that these wastes contain bioactive compounds of interest with great potential to generate high value added products.


Assuntos
Leite de Soja , Antioxidantes/análise , Farinha , Manipulação de Alimentos
15.
Membranes (Basel) ; 11(8)2021 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-34436361

RESUMO

This study aimed to differentiate human mesenchymal stem cells (hMSCs) from the human umbilical cord in cholinergic-like neurons using a natural membrane. The isolation of hMSCs from Wharton's jelly (WJ) was carried out using "explant" and mononuclear cells by the density gradient from umbilical blood and characterized by flow cytometry. hMSCs were seeded in a natural functional biopolymer membrane to produce neurospheres. RT-PCR was performed on hMSCs and neurospheres derived from the umbilical cord. Neural precursor cells were subjected to a standard cholinergic-like neuron differentiation protocol. Dissociated neurospheres, neural precursor cells, and cholinergic-like neurons were characterized by immunocytochemistry. hMSCs were CD73+, CD90+, CD105+, CD34- and CD45- and demonstrated the trilineage differentiation. Neurospheres and their isolated cells were nestin-positive and expressed NESTIN, MAP2, ßIII-TUBULIN, GFAP genes. Neural precursor cells that were differentiated in cholinergic-like neurons expressed ßIII-TUBULIN protein and choline acetyltransferase enzyme. hMSCs seeded on the natural membrane can differentiate into neurospheres, obtaining neural precursor cells without growth factors or gene transfection before cholinergic phenotype differentiation.

16.
Int J Biol Macromol ; 189: 597-606, 2021 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-34418421

RESUMO

Millions of people are burned worldwide every year and 265,000 of the cases are fatal. The development of burn treatment cannot consist only of the administration of a single drug. Due to the infection risk, antibiotics are used in conjunction with gels and damp bandages. In this work, an inexpensive curative based on silver sulfadiazine (SS) and natural rubber latex (NRL) was developed to treat burn wounds. It was produced by the casting method. The infrared spectrum presented no interaction between drug and biopolymer. At the same time, electronic micrographs showed that the SS crystals are inserted on the polymeric dressing surface. Mechanical properties after the drug incorporation were considered suitable for dermal application. About 32.4% of loaded SS was released in 192 h by the dressings that also inhibited the growth of Candida albicans and Candida parapsilosis at 75.0 and 37.5 µg·mL-1, respectively. The curative proved to be biocompatible when applied to fibroblast cells, in addition to enhancing cellular proliferation and, in the hemocompatibility test, no hemolytic effects were observed. The good results in mechanical, antifungal and biological assays, combined with the average bandage cost of $0.10, represent an exciting alternative for treating burn wounds.


Assuntos
Bandagens , Queimaduras/tratamento farmacológico , Queimaduras/microbiologia , Candida/fisiologia , Borracha/farmacologia , Sulfadiazina de Prata/uso terapêutico , Animais , Antifúngicos/farmacologia , Candida/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Cinética , Camundongos , Testes de Sensibilidade Microbiana , Células NIH 3T3 , Ovinos , Sulfadiazina de Prata/química , Sulfadiazina de Prata/farmacologia , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier
17.
Mater Sci Eng C Mater Biol Appl ; 126: 112126, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34082943

RESUMO

The past decades have witnessed tremendous progress in biomaterials in terms of functionalities and applications. To realize various functions such as tissue engineering, tissue repair, and controlled release of therapeutics, a biocompatible and biologically active material is often needed. However, it is a difficult task to find either synthetic or natural materials suitable for in vivo applications. Nature has provided us with the natural rubber latex from the rubber tree Hevea brasiliensis, a natural polymer that is biocompatible and has been proved as inducing tissue repair by enhancing the vasculogenesis process, guiding and recruiting cells responsible for osteogenesis, and acting as a solid matrix for controlled drug release. It would be extremely useful if medical devices can be fabricated with materials that have these biological properties. Recently, various types of natural rubber latex-based biomedical devices have been developed to enhance tissue repair by taking advantage of its biological properties. Most of them were used to enhance tissue repair in chronic wounds and critical bone defects. Others were used to design drug release systems to locally release therapeutics in a sustained and controlled manner. Here, we summarize recent progress made in these areas. Specifically, we compare various applications and their performance metrics. We also discuss critical problems with the use of natural rubber latex in biomedical applications and highlight future opportunities for biomedical devices produced either with pre-treated natural rubber latex or with proteins purified from the natural rubber latex.


Assuntos
Hevea , Liberação Controlada de Fármacos , Hevea/metabolismo , Látex , Proteínas de Plantas/metabolismo , Proteínas , Borracha
18.
J Appl Biomater Funct Mater ; 19: 22808000211005383, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33781110

RESUMO

The incorporation of drugs and bioactive compounds in the natural rubber latex (NRL) matrix has been an alternative for the development of transdermal release membranes. Ibuprofen (IBF) is known to be used to treat inflammatory diseases, but when administered orally, high concentrations can cause some adverse problems. In this work, the incorporation of IBF in the NRL membranes was evaluated by physical-chemical, in vitro permeation, hemocompatibility and molecular modeling assays. In addition, the in vitro release profile of IBF in acid and basic media was analyzed during 96 h. The IBF-NRL membrane exhibited the absence of intermolecular bonding that could hinder drug release and presented compatible mechanical properties for applications as a cutaneous adhesive (0.58 and 1.12 MPa to Young's modulus and rupture tension, respectively). The IBF-NRL system did not present a significant hemolysis degree (1.67%) within 24 h. The release test indicated that in the first hours of the study, 48.5% IBF was released at basic pH and 22.5% at acidic pH, which is characteristic of a burst effect. Then, a stable release profile was observed until the end of the assay, with total IBF release of 60% in alkaline medium and 50% in acidic medium. The drug permeation results indicated that the IBF-NRL membranes can be used for the local skin treatment with permeation of 3.11% of IBF. Dynamic Molecular simulations indicated a pronounced electric dipole in the ionized form of IBF, which suggests a more effective interaction with water, explaining the efficient drug release in alkaline solutions. In general, the results demonstrate that the IBF-NRL membrane has great potential for a new adhesive that can be used for the treatment of inflammatory processes and injuries.


Assuntos
Ibuprofeno , Borracha , Liberação Controlada de Fármacos
19.
J Biomater Sci Polym Ed ; 32(1): 93-111, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32897812

RESUMO

Skin wound infection requires carefully long-term treatment with an immense financial burden to healthcare systems worldwide. Various strategies such as drug delivery systems using polymer matrix from natural source have been used to enhance wound healing. Natural rubber latex (NRL) from Hevea brasiliensis has shown angiogenic and tissue repair properties. Gentamicin sulfate (GS) is a broad-spectrum antibiotic which inhibits the growth of a wide variety of microorganisms and, because of this, it has also been applied topically for treatment of local infections. The aim of this study was to develop a GS release system using NRL as matrix for Staphylococcus aureus and Escherichia coli infected skin ulcers treatment, without changing drug antibiotic properties. The matrix did not change the GS antimicrobial activity against S. aureus and E. coli strains. Moreover, the NRL-GS biomembrane did not exhibit hemolytic activity, being non-toxic to red blood cells. The eluates of NRL-GS biomembranes and GS solutions did not significantly reduce the survival of Caenorhabditis elegans worms for 24 h at any of the tested concentrations. Thus, these results emphasize that the NRL-GS biomembrane proved to be a promising biomaterial for future studies on the development of dressings for topical uses, inexpensive and practicable, keeping drug antibiotic properties against pathogens and to reduce the side effects.


Assuntos
Úlcera Cutânea , Staphylococcus aureus , Antibacterianos/farmacologia , Biopolímeros , Escherichia coli , Gentamicinas , Humanos
20.
Mater Sci Eng C Mater Biol Appl ; 119: 111589, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33321634

RESUMO

Wounds can take longer to heal in diabetic patients, increasing the risk of infections and other complications. The most common wounds in diabetic patients are diabetic foot ulcers, a severe complication associated with diabetes mellitus. The United States alone spends $18.7 billion annually on care for these wounds including pain and infection management. If improperly managed, infected lesions may require amputation. The enormous cost associated with wound care and the dire consequences if not cared for properly, emphasize the need to develop strategies to accelerate the healing of diabetic foot wounds. Natural rubber latex (NRL), extracted from Hevea brasiliensis (the rubber tree), has been widely applied as a carrier system for several pharmacologically active compounds. Furthermore, it has been shown to encourage angiogenesis, facilitate cell adhesion, and accelerate wound healing. When NRL dressings are applied to wounds of diabetic patients, exudate release is upregulated. The production of exudate is essential to wound healing as it provides the nutrients, proteins, cells, and environment required for regeneration. Despite its benefits, it is necessary to control excess exudate to avoid prolonged healing resulting from dermatitis, maceration of the wound edges, and lesion growth. In order to solve the problem of excessive exudate release induced by NRL membrane application, we aimed to regulate humidity by absorbing excess exudate and increase water vapor transmission. We developed a highly absorptive, permeable, alginate loaded NRL dressing. Adding alginate to NRL membranes, swelling was increased up to 80-fold, absorbing 4.80 g of water per gram of dry membrane. Moreover, water vapor transmission was improved drastically as the material transmitted 480% more water vapor than pure NRL membranes. Furthermore, in vitro tests demonstrated not only that the membranes are biocompatible, but that they also enhance cell proliferation. Through a cell proliferation assay, we observed that fibroblast proliferation was improved by the presence of NRL while the keratinocytes benefit from the presence of alginate. The NRL-alginate dressings have great potential to improve diabetic wound care by accelerating the healing process.


Assuntos
Diabetes Mellitus , Látex , Alginatos , Bandagens , Exsudatos e Transudatos , Humanos , Cicatrização
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