Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 39
Filtrar
1.
AAPS PharmSciTech ; 23(6): 212, 2022 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-35918472

RESUMO

Squamous cell carcinoma (SCC) represents 20% of cases of non-melanoma skin cancer, and the most common treatment is the removal of the tumor, which can leave large scars. 5-Fluorouracil (5FU) is a drug used in the treatment of SCC, but it is highly hydrophilic, resulting in poor skin penetration in topical treatment. Some strategies can be used to increase the cutaneous penetration of the drug, such as the combination of liposomes containing penetration enhancers, for instance, surfactants, associated with the use of microneedling. Thus, the present work addresses the development of liposomes with penetration enhancers, such as sorbtitan monolaurate, span 20, for topical application of 5-FU and associated or not with the use of microneedling for skin delivery. Liposomes were developed using the lipid film hydration, resulting in particle size, polydispersity index, zeta potential, and 5-FU encapsulation efficiency of 88.08 nm, 0.169, -12.3 mV, and 50.20%, respectively. The presence of span 20 in liposomes potentiated the in vitro release of 5-FU. MTT assay was employed for cytotoxicity evaluation and the IC50 values were 0.62, 30.52, and 24.65 µM for liposomes with and without span 20 and 5-FU solution, respectively after 72-h treatment. Flow cytometry and confocal microscopy analysis evidenced high cell uptake for the formulations. In skin penetration studies, a higher concentration of 5-FU was observed in the epidermis + dermis, corresponding to 1997.71, 1842.20, and 2585.49 ng/cm2 in the passive penetration and 3214.07, 2342.84, and 5018.05 ng/cm2 after pretreatment with microneedles, for solution, liposome without and with span 20, respectively. Therefore, herein, we developed a nanoformulation for 5-FU delivery, with suitable physicochemical characteristics, potent skin cancer cytotoxicity, and cellular uptake. Span 20-based liposomes increased the skin penetration of 5-FU in association of microneedling. Altogether, the results shown herein evidenced the potential of the liposome containing span 20 for topical delivery of 5-FU.


Assuntos
Fluoruracila , Neoplasias Cutâneas , Hexoses , Humanos , Lipossomos/metabolismo , Tamanho da Partícula , Pele/metabolismo , Absorção Cutânea , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/metabolismo
2.
Molecules ; 26(9)2021 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-34063701

RESUMO

Agricultural production is influenced by the water content in the soil and availability of fertilizers. Thus, superabsorbent hydrogels, based on polyacrylamide, natural cashew tree gum (CG) and potassium hydrogen phosphate (PHP), as fertilizer and water releaser were developed. The structure, morphology, thermal stability and chemical composition of samples of polyacrylamide and cashew tree gum hydrogels with the presence of fertilizer (HCGP) and without fertilizer (HCG) were investigated, using X-ray diffractometry (XRD), Fourier Transformed Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), Thermogravimetric Analysis (TGA/DTG) and Energy Dispersive Spectroscopy (EDS). Swelling/reswelling tests, textural analysis, effect of pH, release of nutrients and kinetics were determined; the ecotoxicity of the hydrogels was investigated by the Artemia salina test. The results showed that PHP incorporation in the hydrogel favored the crosslinking of chains. This increased the thermal stability in HCGP but decreased the hardness and adhesion properties. The HCGP demonstrated good swelling capacity (~15,000 times) and an excellent potential for reuse after fifty-five consecutive cycles. The swelling was favored in an alkaline pH due to the ionization of hydrophilic groups. The sustained release of phosphorus in HCGP was described by the Korsmeyer-Peppas model, and Fickian diffusion is the main fertilizer release mechanism. Finally, the hydrogels do not demonstrate toxicity, and HCGP has potential for application in agriculture.


Assuntos
Resinas Acrílicas/química , Anacardium , Hidrogéis/química , Gomas Vegetais/química , Animais , Artemia , Reagentes de Ligações Cruzadas , Preparações de Ação Retardada , Difusão , Fertilizantes , Hidrogênio/química , Concentração de Íons de Hidrogênio , Cinética , Microscopia Eletrônica de Varredura , Nutrientes , Fosfatos/química , Fósforo , Polímeros/química , Polissacarídeos/química , Potássio/química , Espectroscopia de Infravermelho com Transformada de Fourier , Árvores , Água , Difração de Raios X
3.
Int J Mol Sci ; 18(11)2017 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-29137157

RESUMO

Silver nanoparticles have been shown to possess considerable antibacterial activity, but in vivo applications have been limited due to the inherent, but low, toxicity of silver. On the other hand, silver nanoparticles could provide cutaneous protection against infection, due to their ability to liberate silver ions via a slow release mechanism, and their broad-spectrum antimicrobial action. Thus, in this work, we describe the development of a carboxymethyl cellulose-based hydrogel containing silver nanoparticles. The nanoparticles were prepared in the hydrogel in situ, utilizing two variants of cashew gum as a capping agent, and sodium borohydride as the reducing agent. This gum is non-toxic and comes from a renewable natural source. The particles and gel were thoroughly characterized through using rheological measurements, UV-vis spectroscopy, nanoparticles tracking analysis, and transmission electron microscopy analysis (TEM). Antibacterial tests were carried out, confirming antimicrobial action of the silver nanoparticle-loaded gels. Furthermore, rat wound-healing models were used and demonstrated that the gels exhibited improved wound healing when compared to the base hydrogel as a control. Thus, these gels are proposed as excellent candidates for use as wound-healing treatments.


Assuntos
Anacardium/química , Antibacterianos/farmacologia , Carboximetilcelulose Sódica/química , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Nanopartículas Metálicas/química , Ácidos Ftálicos/química , Prata/farmacologia , Cicatrização/efeitos dos fármacos , Animais , Masculino , Nanopartículas Metálicas/ultraestrutura , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Pseudomonas aeruginosa/efeitos dos fármacos , Ratos Wistar , Reologia , Staphylococcus aureus/efeitos dos fármacos
4.
Int J Biol Macromol ; 275(Pt 1): 133588, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38960246

RESUMO

The understanding of cancer immunity and antitumor factors generated by natural polysaccharides is not yet fully comprehended. Polysaccharides, like cashew gum (CG), can exhibit immunomodulatory action and may assist in the antitumor process and side effects relieve. This study aimed to determine the antitumor effect of CG alone or in combination with cyclophosphamide (CTX), and its interactions with immune cells, in a murine melanoma model, using the B16-F10 cell line. Tumor growth inhibition, hematological, histopathological, ELISA, flow cytometry, immunofluorescence, and qRT-PCR analyses were performed to elucidate the antitumor potential, involvement of immune cells, and potential toxic effects. CG showed significant tumor growth inhibition, reaching up to 42.9 % alone and 51.4 % in combination with CTX, with mild toxicity to organs. CG enhanced leukocyte count, even in the presence of CTX. Furthermore, CG influenced the activation of tumor-associated macrophages (TAM), characterized by an increase in Il4, as well as a reduction in Ifng, Il1b, Tgfb, and Il6 gene expression. Nevertheless, these effects did not compromise the antitumor activity of CG. In summary, the combination of CG with CTX is a promising approach for leukopenia, one of the most important side effects of cancer treatment and deserves further investigation.

5.
Carbohydr Polym ; 342: 122356, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39048219

RESUMO

In this study, we report the synthesis and characterization of pH-responsive nanoconjugates for targeted drug delivery. Galactomannan extracted from D. regia seeds was oxidized to form aldehyde groups, achieving a percentage of oxidation of 25.6 %. The resulting oxidized galactomannan (GMOX) was then copolymerized with PINIPAm-NH2, yielding a copolymer. The copolymer exhibited signals from both GMOX and PNIPAm-NH2 in its NMR spectrum, confirming successful copolymerization. Critical association concentration (CAC) studies revealed the formation of nanostructures, with lower CAC values observed at higher temperatures. The copolymer and GMOX reacted with doxorubicin (DOX), resulting in nanoconjugates with controlled drug release profiles, especially under acidic conditions similar to tumor microenvironments. Cytotoxicity assays demonstrated significant efficacy of the nanoconjugates against melanoma cells with reduced toxicity towards healthy cells. These findings underscore the potential of the pH-responsive nanoconjugates as promising candidates for targeted cancer therapy, offering improved therapeutic efficacy and reduced systemic side effects.


Assuntos
Doxorrubicina , Galactose , Mananas , Nanoconjugados , Doxorrubicina/farmacologia , Doxorrubicina/química , Mananas/química , Mananas/farmacologia , Galactose/química , Galactose/análogos & derivados , Humanos , Nanoconjugados/química , Concentração de Íons de Hidrogênio , Liberação Controlada de Fármacos , Linhagem Celular Tumoral , Portadores de Fármacos/química , Sobrevivência Celular/efeitos dos fármacos , Antibióticos Antineoplásicos/farmacologia , Antibióticos Antineoplásicos/química , Antineoplásicos/química , Antineoplásicos/farmacologia
6.
Chem Biol Interact ; 398: 111115, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38908811

RESUMO

In the present study, the effect of sulfonamide-chalcone 185 (SSC185) was investigated against B16-F10 metastatic melanoma cells aggressive actions, besides migration and adhesion processes, by in silico and in vitro assays. In silico studies were used to characterize the pharmacokinetic profile and possible targets of SSC185, using the pkCSM web server, and docking simulations with AutoDock Tools. Furthermore, the antimetastatic effect of SSC185 was investigated by in vitro experiments using MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide), colony, scratch, and cell adhesion assays, and atomic force microscopy (AFM). The molecular docking results show better affinity of SSC185 with the metalloproteinases-2 (MMP-2) and α5ß1 integrin. SSC185 effectively restricts the formation of colonies, migration, and adhesion of B16-F10 metastatic melanoma cells. Through the AFM images changes in cells morphology was identified, with a decrease in the filopodia and increase in the average cellular roughness. The results obtained demonstrate the potential of this molecule in inhibit the primordial steps for metastasis, which is responsible for a worse prognosis of late stage cancer, being the main cause of morbidity among cancer patients.


Assuntos
Adesão Celular , Movimento Celular , Chalcona , Simulação de Acoplamento Molecular , Sulfonamidas , Movimento Celular/efeitos dos fármacos , Adesão Celular/efeitos dos fármacos , Sulfonamidas/farmacologia , Sulfonamidas/química , Camundongos , Animais , Linhagem Celular Tumoral , Chalcona/farmacologia , Chalcona/química , Chalcona/análogos & derivados , Metaloproteinase 2 da Matriz/metabolismo , Melanoma Experimental/patologia , Melanoma Experimental/tratamento farmacológico , Melanoma Experimental/metabolismo , Microscopia de Força Atômica , Antineoplásicos/farmacologia , Antineoplásicos/química , Chalconas/farmacologia , Chalconas/química , Humanos
7.
Int J Biol Macromol ; 268(Pt 1): 131661, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38641286

RESUMO

In this study, two nanoemulsions were formulated with essential oil (EO) of Ocimum gratissimum with (EON) or without (EOE) cashew gum (CG). Subsequently, inhibition of melanosis and preservation of the quality of shrimp stored for 16 days at 4 ± 0.5 °C were evaluated. A computational approach was performed to predict the system interactions. Dynamic light scattering (DLS) and atomic force microscopy (AFM) were used for nanoparticle analysis. Gas chromatography and flame ionization detector (GC-FID) determined the chemical composition of the EO constituents. Shrimps were evaluated according to melanosis's appearance, psychrotrophic bacteria's count, pH, total volatile basic nitrogen, and thiobarbituric acid reactive substances. EON exhibited a particle size three times smaller than EOE. The shrimp treated with EON showed a more pronounced sensory inhibition of melanosis, which was considered mild by the 16th day. Meanwhile, in the other groups, melanosis was moderate (EOE) or severe (untreated group). Both EON and EOE treatments exhibited inhibition of psychrotrophic bacteria and demonstrated the potential to prevent lipid oxidation, thus extending the shelf life compared to untreated fresh shrimp. EON with cashew gum, seems more promising due to its physicochemical characteristics and superior sensory performance in inhibiting melanosis during shrimp preservation.


Assuntos
Anacardium , Ocimum , Óleos Voláteis , Animais , Óleos Voláteis/farmacologia , Óleos Voláteis/química , Ocimum/química , Anacardium/química , Penaeidae/química , Gomas Vegetais/química , Conservação de Alimentos/métodos
8.
Int J Biol Macromol ; 274(Pt 2): 133048, 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38857734

RESUMO

Epiisopiloturine (EPI) is a compound found in jaborandi leaves with antiparasitic activity, which can be enhanced when incorporated into nanoparticles (NP). Cashew Gum (CG), modified by carboxymethylation, is used to produce polymeric nanomaterials with biological activity. In this study, we investigated the antimicrobial potential of carboxymethylated CG (CCG) NP containing EPI (NPCCGE) and without the alkaloid (NPCCG) against bacteria and parasites of the genus Leishmania. We conducted theoretical studies, carboxymethylated CG, synthesized NP by nanoprecipitation, characterized them, and tested them in vitro. Theoretical studies confirmed the stability of modified carbohydrates and showed that the EPI-4A30 complex had the best interaction energy (-8.47 kcal/mol). CCG was confirmed by FT-IR and presented DSabs of 0.23. NPCCG and NPCCGE had average sizes of 221.94 ± 144.086 nm and 247.36 ± 3.827 nm, respectively, with homogeneous distribution and uniform surfaces. No NP showed antibacterial activity or cytotoxicity to macrophages. NPCCGE demonstrated antileishmanial activity against L. amazonensis, both in promastigote forms (IC50 = 9.52 µg/mL, SI = 42.01) and axenic amastigote forms (EC50 = 6.6 µg/mL, SI = 60.60). The results suggest that nanostructuring EPI in CCG enhances its antileishmanial activity.

9.
J Pharm Pharmacol ; 76(6): 732-742, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38546507

RESUMO

OBJECTIVES: Angico gum (AG) (Anadenanthera colubrina var. Cebil [Griseb.] Altschul) is utilized by some Brazilian communities to alleviate symptoms from gastroesophageal reflux disease. Here, we aimed to investigate the "in vitro" topical protective capacity of AG on human esophageal mucosa. METHODS: Biopsies of the distal esophageal mucosa were collected from 35 patients with heartburn (24 non-erosive and 11 with erosive oesophagitis (EE)) and mounted in Üssing chambers. AG was applied topically, followed by exposure with acid solution (pH 2.0 or pH 1.0), where transepithelial electrical resistance (TER) and The transepithelial permeability for fluorescein was assessed. The incubation of the AG labeled with FITC in the esophageal mucosa was localized by fluorescence microscopy. KEY FINDINGS: Pretreatment with AG prevented the drop in TER induced by acid solution, as well as significantly decreases the fluorescein permeability in non-erosive patients. The protective effect of AG was sustained for up to 120 min both in biopsies of non-erosive and erosive esophagitis. Confocal microscope images showed mucosal luminal adherence of FITC-labeled AG. CONCLUSION: AG had a prolonged topical protective effect against acid solution in mucosal biopsies of patients with non-erosive and erosive esophagitis.


Assuntos
Mucosa Esofágica , Refluxo Gastroesofágico , Humanos , Refluxo Gastroesofágico/tratamento farmacológico , Refluxo Gastroesofágico/prevenção & controle , Mucosa Esofágica/efeitos dos fármacos , Mucosa Esofágica/patologia , Mucosa Esofágica/metabolismo , Masculino , Feminino , Pessoa de Meia-Idade , Adulto , Permeabilidade , Impedância Elétrica , Administração Tópica , Biopolímeros , Idoso , Fluoresceína/administração & dosagem , Esôfago/efeitos dos fármacos , Esôfago/patologia , Esôfago/metabolismo , Azia/tratamento farmacológico , Azia/prevenção & controle , Relevância Clínica
10.
Int J Biol Macromol ; 243: 125254, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37295699

RESUMO

The present work explores the esterification reaction in the polysaccharide extracted from the seaweed Gracilaria birdiae and investigates its antioxidant potential. The reaction process was conducted with phthalic anhydride at different reaction times (10, 20 and 30 min), using a molar ratio of 1:2 (polymer: phthalic anhydride). Derivatives were characterized by FTIR, TGA, DSC and XRD. The biological properties of derivatives were investigated by assays of cytotoxicity and antioxidant activity (2,2-diphenyl-1-picrylhydroxyl - DPPH and 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt - ABTS). The results obtained by FT-IR confirmed the chemical modification, there was a reduction related to the presence of carbonyl and hydroxyl groups when compared to the in nature polysaccharide spectrum. TGA analysis showed a change in the thermal behavior of the modified materials. X-ray diffraction, it was shown that the in nature polysaccharide appeared as an amorphous material, while the material obtained after the chemical modification process had increased crystallinity, due to the introduction of phthalate groups. For the biological assays, it was observed that the phthalate derivative was more selective than the unmodified material for the murine metastatic melanoma tumor cell line (B16F10), revealing a good antioxidant profile for DPPH and ABTS radicals.


Assuntos
Antineoplásicos , Gracilaria , Animais , Camundongos , Antioxidantes/química , Anidridos Ftálicos , Galactanos , Espectroscopia de Infravermelho com Transformada de Fourier , Antineoplásicos/química , Polissacarídeos/química
11.
Laryngoscope ; 133(1): 162-168, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35258096

RESUMO

OBJECTIVE: This study aimed to evaluate the in vivo protective effect of the angico gum biopolymer in reducing the inflammatory response and preserving the integrity of the laryngeal and esophageal mucosa. STUDY DESIGN: Animal study. METHODS: A murine surgical model of gastroesophageal reflux disease was accomplished and subsequently treated with angico gum or omeprazole. On days 3 and 7 post surgery, samples of the larynx and esophagus, respectively, were collected to measure the level of inflammation (wet weight and myeloperoxidase activity) and mucosal integrity (transepithelial electrical resistance and mucosal permeability to fluorescein). RESULTS: Angico gum and omeprazole decreased laryngeal inflammation (wet weight and myeloperoxidase activity) and dramatically improved the integrity of the laryngeal mucosa. It also reduced inflammation (decreased wet weight and myeloperoxidase activity) of the esophagus and preserved the barrier function (inferred by assessing the integrity of the mucosa). CONCLUSION: This study demonstrates the protective effect of angico gum in an experimental gastroesophageal reflux disease model. Angico gum attenuates inflammation and impairment of the mucosal barrier function not only in the larynx but also in the esophagus. LEVEL OF EVIDENCE: NA Laryngoscope, 133:162-168, 2023.


Assuntos
Mucosa Esofágica , Refluxo Gastroesofágico , Camundongos , Animais , Refluxo Gastroesofágico/tratamento farmacológico , Impedância Elétrica , Mucosa , Modelos Animais de Doenças
12.
Pharmaceuticals (Basel) ; 16(2)2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-37259411

RESUMO

Hydrogels are structures that have value for application in the area of tissue engineering because they mimic the extracellular matrix. Naturally obtained polysaccharides, such as chitosan (CH) and cashew gum, are materials with the ability to form polymeric networks due to their physicochemical properties. This research aimed to develop a scaffold based on chitosan and phthalated cashew tree gum and test it as a support for the growth of human mesenchymal stem cells. In this study, phthalation in cashew gum (PCG) was performed by using a solvent-free route. PCG-CH scaffold was developed by polyelectrolyte complexation, and its ability to support adherent stem cell growth was evaluated. The scaffold showed a high swelling rate. The pore sizes of the scaffold were analyzed by scanning electron microscopy. Human dental pulp stem cells (hDPSCs) were isolated, expanded, and characterized for their potential to differentiate into mesenchymal lineages and for their immunophenotypic profile. Isolated mesenchymal stem cells presented fibroblastoid morphology, plastic adhesion capacity, and differentiation in osteogenic, adipogenic, and chondrogenic lineages. Mesenchymal stem cells were cultured in scaffolds to assess cell adhesion and growth. The cells seeded on the scaffold showed typical morphology, attachment, and adequate distribution inside the matrix pores. Thus, cells seeded in the scaffold may improve the osteoinductive and osteoconductive properties of these biomaterials.

13.
Int J Biol Macromol ; 230: 123272, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36649864

RESUMO

Nanotechnology is a crucial technology in recent years has resulted in new and creative applications of nanomedicine. Polymeric nanoparticles have increasing demands in pharmaceutical applications and require high reproducibility, homogeneity, and control over their properties. Work explores the use of cashew phthalate gum (PCG) as a particle-forming polymer. PCG exhibited a pH-sensitive behavior due to the of acid groups on its chains, and control drug release. We report the development of nanoparticles carrying benznidazole. Formulations were characterized by DLS, encapsulation efficiency, drug loading, FTIR, pH-responsive behavior, release, and in vitro kinetics. Interaction between polymer and drug was an evaluated by molecular dynamics. Morphology was observed by SEM, and in vitro cytotoxicity by MTT assay. Trypanocidal effect for epimastigote and trypomastigote forms was also evaluated. NPs responded to the slightly basic pH, triggering the release of BNZ. In acidic medium, they presented small size, spherical shape, and good stability. It was indicated NP with enhanced biological activity, reduced cytotoxicity, high anti T. cruzi performance, and pH-sensitive release. This work investigated properties related to the development and enhancement of nanoparticles. PCG has specific physicochemical properties that make it a promising alternative to drug delivery, however, there are still challenges to be overcome.


Assuntos
Anacardium , Nanopartículas , Trypanosoma cruzi , Reprodutibilidade dos Testes , Nanopartículas/química , Liberação Controlada de Fármacos , Polímeros/farmacologia , Concentração de Íons de Hidrogênio , Portadores de Fármacos/farmacologia
14.
Int J Biol Macromol ; 232: 123058, 2023 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-36669633

RESUMO

Lemon gum (LG) obtained from Citrus × latifolia in Brazil was isolated and characterized. In addition, gum biocompatibility was evaluated in vitro and in vivo by Galleria mellonella and mice model. The cytotoxicity against tumor cells was also evaluated. The ratio of arabinose:galactose: rhamnose:4-OMe-glucuronic acid was 1:0.65:0.06:0.15. Small traces of protein were detected, emphasizing the isolate purity. Molar mass was 8.08 × 105 g/mol, with three different degradation events. LG showed antiproliferative activity against human prostate adenocarcinoma cancer cells, with percentage superior to 50 %. In vivo toxicity models demonstrated that LG is biocompatible polymer, with little difference in the parameters compared to control group. These results demonstrate advance in the study of LG composition and toxicity, indicating a potential for several biomedical and biotechnological future applications.


Assuntos
Adenocarcinoma , Citrus , Masculino , Animais , Camundongos , Humanos , Próstata , Galactanos , Adenocarcinoma/tratamento farmacológico
15.
Int J Biol Macromol ; 182: 1419-1436, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33965482

RESUMO

The natural polysaccharides, due to their structural diversity, commonly present very distinct solubility and physical chemical properties and additionally have intrinsic biological activities that, gene-rally, reveal themselves in a light way. The chemical modification of the molecular structure can improve these parameters. In this review, original articles that approached the quaternization of polysaccharides for purposes of biological application were selected, without limitation of year of publication, in the databases Scopus, Web of Science and PubMed. The results obtained from the bibliographic survey indicate that the increase in positive charges caused by quaternization improves the interaction between modified polysaccharides and structures that have negative charges on their surface, such as the cell wall of microorganisms and some cells in the human body, such as the DNA. This greater interaction is reflected as an increase in the biological activity of all polysaccharides broached in this study. Another important data obtained was the fact that the chemical changes did not affect or irrelevantly affect the toxicity of almost all of the polysaccharides that were quaternized. Therefore, polysaccharide quaternization is a safe and effective way to obtain improvements in the biological behavior of these macromolecules.


Assuntos
Polissacarídeos/química , Polissacarídeos/farmacologia , Anti-Infecciosos/farmacologia , Antineoplásicos/farmacologia , Antioxidantes/farmacologia , Bases de Dados como Assunto , Conformação Molecular , Polissacarídeos/toxicidade
16.
J Mater Chem B ; 9(34): 6825-6835, 2021 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-34369539

RESUMO

This research reports, for the first time, the immobilization of an enzyme - Rhus vernificera laccase - on cashew gum (CG) nanoparticles (NPs) and its application as a biological layer in the design and development of an electrochemical biosensor. Laccase-CG nanoparticles (LacCG-NPs) were prepared by the nanoprecipitation method and characterized by UV-Vis spectrophotometry, atomic force microscopy, scanning electron microscopy, attenuated total reflectance-Fourier-transform infrared spectroscopy, circular dichroism, cyclic voltammetry, and electrochemical impedance spectroscopy. The average size and stability of the NPs were predicted by DLS and zeta potential. The ATR-FTIR results clearly demonstrated an interaction between -NH and -OH groups to form LacCG-NPs. The average size found for LacCG-NPs was 280 ± 53 nm and a polydispersity index of 0.309 ± 0.08 indicated a good particle size distribution. The zeta potential shows a good colloidal stability. The use of a natural product to prepare the enzymatic nanoparticles, its easy synthesis and the immobilization efficiency should be highlighted. LacCG-NPs were successfully applied as a biolayer in the development of an amperometric biosensor for catechol detection. The resulting device showed a low response time (6 s), good sensitivity (7.86 µA µM-1 cm-2), wide linear range of 2.5 × 10-7-2.0 × 10-4 M, and low detection limit (50 nM).


Assuntos
Materiais Biocompatíveis/química , Técnicas Biossensoriais , Catecóis/análise , Lacase/química , Nanopartículas/química , Gomas Vegetais/química , Anacardium/química , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/metabolismo , Configuração de Carboidratos , Técnicas Eletroquímicas , Lacase/metabolismo , Teste de Materiais , Modelos Moleculares , Nanopartículas/metabolismo , Tamanho da Partícula , Gomas Vegetais/isolamento & purificação , Gomas Vegetais/metabolismo , Toxicodendron/enzimologia
17.
Int J Biol Macromol ; 193(Pt A): 450-456, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34688680

RESUMO

Enoxaparin is an effective biological molecule for prevention and treatment of coagulation disorders. However, it is poorly absorbed in the gastrointestinal tract. In this study, we developed an Eudragit® L100 coated chitosan core shell nanoparticles for enoxaparin oral delivery (Eud/CS/Enox NPs) through a completely eco-friendly method without employing any high-energy homogenizer technique and any organic solvents. Spherical nanocarriers were successfully prepared with particle size lower than 300 nm, polydispersity index about 0.12 and zeta potential higher than +25 mV, entrapment efficiency greater than 95% and the in vitro release behavior confirms the good colloidal stability and the successful Eudragit® L100 coating process demonstrated by negligible cumulative enoxaparin release (<10%) when the particles are submitted to simulated gastric fluid conditions. Finally, we demonstrated that the core-shell structure of the particle influenced the drug release mechanism of the formulations, indicating the presence of the Eudragit® L100 on the surface of the particles. These results suggested that enteric-coating approach and drug delivery nanotechnology can be successfully explored as potential tools for oral delivery of enoxaparin.


Assuntos
Quitosana/química , Portadores de Fármacos/química , Enoxaparina/química , Nanopartículas/química , Liberação Controlada de Fármacos , Tamanho da Partícula
18.
Int J Biol Macromol ; 190: 801-809, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34508723

RESUMO

We developed a new hydrophobic polymer based on angico gum (AG), and we produced new nanoparticles to expand the applications of natural polysaccharides in nanomedicine. Phthalate angico gum (PAG) was characterized by 1H NMR, FTIR, elementary analysis, solubility, XRD, and TG. PAG was a hydrophobic and semi-crystalline material, a relevant characteristic for drug delivery system applications. As a proof of concept, nevirapine (NVP) was selected for nanoparticles development. Plackett-Burman's experimental design was used to understand the influence of several factors in nanoparticles production. PAG proved to be a versatile material for producing nanoparticles with different characteristics. Optimized nanoparticles were produced using desirability parameters. NVP-loaded PAG nanoparticles formulation showed 202.1 nm of particle size, 0.23 of PDI, -17.1 of zeta potential, 69.8 of encapsulation efficiency, and promoted modified drug release for 8 h. Here we show that PAG presents as a promising biopolymer for drug delivery systems.


Assuntos
Química Verde , Nanopartículas/química , Nanotecnologia , Ácidos Ftálicos/química , Gomas Vegetais/química , Liberação Controlada de Fármacos , Humanos , Microscopia de Força Atômica , Peso Molecular , Nevirapina/farmacologia , Tamanho da Partícula , Espectroscopia de Prótons por Ressonância Magnética , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria , Difração de Raios X
19.
Int J Biol Macromol ; 166: 144-154, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33190824

RESUMO

Aminated poly(N-isopropylacrylamide) (PNIPAm-NH2) was grafted onto oxidized galactomannan polysaccharide extracted from Delonix regia (OXGM) via Schiff base reaction by a simple, rapid synthetic route, deprived of the use of organic solvents. Grafting was confirmed by FTIR and 1H NMR and the self-organizing ability of the obtained nanoparticle copolymers was investigated by dynamic light scattering (DLS). The minimum concentration required for self-organization (CAC) at 25 °C was higher than at 50 °C. Lower critical solution temperature (LCST) was in the range 34-40 °C, depending on both inserted PNIPAm-NH2 molar mass and on the presence of reduced imine bond. Synthesized copolymers are promising candidates for drug delivery as they show good cell viability, particle size around 250 nm and transition temperature closer to that of human body. Reaction success points out to the possibility of use free aldehyde groups of oxidized polysaccharide, not used in the copolymerization, to form a pro-drug with substances that possess NH2 groups in their structure, such as doxorubicin.


Assuntos
Resinas Acrílicas/química , Materiais Biocompatíveis/síntese química , Fabaceae/química , Mananas/química , Galactose/análogos & derivados , Polimerização , Bases de Schiff/química , Sementes/química , Temperatura de Transição
20.
Carbohydr Polym ; 251: 117077, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33142620

RESUMO

The objective of this research was to modify chicha gum with phthalic anhydride to obtain a new biologically active material. The chemical modification of the gum structure was proven through FTIR, elemental analysis, XRD, TG, and DSC. The derived materials demonstrated excellent inhibitory effect against P. aeruginosa and K. pneumoniae species (rating 100% inhibition) and could also inhibit Escherichia coli growth. The best antimicrobial activity observed for the derivatives suggests that chicha gum hydrophobization due to the addition of phthalic groups improved the interaction of these derivatives with bacterial cell wall components. On the other hand, the derivatives increased CC50 in macrophages but did not present acute toxicity or hemolytic activity, indicating that they are promising for use in prophylaxis or treatment of infections caused by Gram-negative bacteria.


Assuntos
Antibacterianos/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Anidridos Ftálicos/química , Gomas Vegetais/química , Sterculia/química , Animais , Sobrevivência Celular , Esterificação , Feminino , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Testes de Sensibilidade Microbiana
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA