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Nanoencapsulation of chemotherapeutics, including doxorubicin, can endow the formulations with unique properties, such as a decrease in adverse effects and toxicity. The chicken embryo model is an alternative and well-accepted strategy for evaluating the toxicity and efficacy of drugs and nanoformulations. Therefore, this study proposes the development of a new lipid nanocarrier for doxorubicin delivery (NanoLip-Dox) and posterior evaluation of toxicological profile and antitumoral efficacy against a breast tumor in chicken embryos. NanoLip-Dox showed a unimodal particle size (< 150 nm), negative zeta potential (-19.5 mV), absence of drug crystals, drug content of 0.099 mg·mL-1, and high entrapment efficiency (95%). NanoLip-Dox did not cause toxicity in the chicken embryos; in contrast, doxorubicin hydrochloride induced moderate irritation in the chorioallantoic membrane (at 862.1 µmol·L-1), a survival rate of 50% (at 1.7 µmol·L-1), and an increase in aspartate aminotransferase (at 862.1, 344.8, and 172.4 µmol·L-1). In addition, NanoLip-Dox (at 1.7 µmol·L-1) showed potent antitumor efficacy with a high tumor remission percentage (40.9 ± 9.7%) compared to the control group (8.6 ± 14.8%). These findings together with the absence of toxicity concerning morphological characteristics, weights of embryos and organs, hematologic parameters, and enzymatic activity (alanine aminotransferase, aspartate aminotransferase, and creatinine) suggest the safety and efficacy of NanoLip-Dox.
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Glioblastoma is the most common and lethal malignant brain tumor. Despite simvastatin (SVT) showing potential anticancer properties, its antitumoral effect against glioblastoma appears limited when the conventional oral administration route is selected. As a consequence, nose-to-brain delivery has been proposed as an alternative route to deliver SVT into the brain. This study aimed to prepare chitosan-coated simvastatin-loaded lipid-core nanocapsules (LNCSVT-chit) suitable for nose-to-brain delivery and capable of fostering antitumor effects against glioblastoma both in vitro and in vivo. Results showed that the nanocapsules present adequate particle size (mean diameter below 200 nm), narrow particle size distribution (PDI < 0.2), positive zeta potential and high encapsulation efficiency (nearly 100%). In vitro cytotoxicity of LNCSVT-chit was comparable to non-encapsulated SVT in C6 rat glioma cells, whereas LNCSVT-chit were more cytotoxic than non-encapsulated SVT after 72 h of incubation against U-138 MG human glioblastoma cell line. In studies carried out in rats, LNCSVT-chit significantly enhanced the amount of drug in rat brain tissue after intranasal administration (2.4-fold) when compared with free SVT. Moreover, LNCSVT-chit promoted a significant decrease in tumor growth and malignancy in glioma-bearing rats in comparison to control and free SVT groups. Additionally, LNCSVT-chit did not cause any toxicity in treated rats. Considered overall, the results demonstrated that the nose-to-brain administration of LNCSVT-chit represents a novel potential strategy for glioblastoma treatment.
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Quitosana , Glioblastoma , Nanocápsulas , Administração Intranasal , Animais , Encéfalo/metabolismo , Linhagem Celular Tumoral , Quitosana/uso terapêutico , Glioblastoma/tratamento farmacológico , Glioblastoma/metabolismo , Lipídeos , Ratos , SinvastatinaRESUMO
Aim: To evaluate the antitumor efficacy of bevacizumab-functionalized nanocapsules in a rat glioblastoma model after the pretreatment with nanocapsules functionalized with a peptide-specific to the epidermal growth factor receptor variant III. Materials & methods: Nanocapsules were prepared, physicochemical characterized and intranasally administered to rats. Parameters such as tumor size, histopathological characteristics and infiltration of CD8+ T lymphocytes were evaluated. Results: The strategy of treatment resulted in a reduction of 87% in the tumor size compared with the control group and a higher infiltration of CD8+ T lymphocytes in tumoral tissue. Conclusion: The block of two different molecular targets using nose-to-brain delivery represents a new and promising approach against glioblastoma.
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Neoplasias Encefálicas , Glioblastoma , Nanocápsulas , Animais , Bevacizumab/uso terapêutico , Encéfalo , Neoplasias Encefálicas/tratamento farmacológico , Linhagem Celular Tumoral , Receptores ErbB , Glioblastoma/tratamento farmacológico , Nanocápsulas/uso terapêutico , Peptídeos/uso terapêutico , RatosRESUMO
Atherosclerosis is a non-resolving inflammatory condition that underlies major cardiovascular diseases.Recent clinical trial using an anti-inflammatory drug has showna reduction of cardiovascular mortality, but increased the susceptibility to infections. For this reason, tissue target anti-inflammatory therapies can represent a better option to regress atherosclerotic plaques. Docosahexaenoic acid (DHA) is a natural omega 3 fatty acidcomponentof algae oil and acts asaprecursor of several anti-inflammatory compounds, such the specialized proresolving lipid mediators(SPMs). During the atherosclerosis process, the inflammatory condition of the endothelium leads to the higher expression of adhesion molecules, such as Endothelial Cell Adhesion Molecule Plate 1 (PECAM-1 or CD31), as part of the innate immune response. Thus, the objective of this study was to develop lipid-core nanocapsules with DHA constituting the nucleus and anti-PECAM-1 on their surface and drive this structure to the inflamed endothelium. Nanocapsules were prepared by interfacial deposition of pre-formed polymer method. Zinc-II was added to bind anti-PECAM-1 to the nanocapsule surface by forming an organometallic complex. Swelling experiment showed that the algae oil act as non-solvent for the polymer (weight constant weight for 60 days, p > 0.428) indicating an adequate material to produce kinetically stable lipid-core nanocapsules (LNC). Five formulations were synthesized: Lipid-core nanocapsules containing DHA (LNC-DHA) or containing Medium-chain triglycerides (LNC-MCT), multi-wall nanocapsules containing DHA (MLNC-DHA) or containing MCT (MLNC-MCT) and the surface-functionalized (anti-PECAM-1) metal-complex multi-wall nanocapsules containing DHA (MCMN-DHA-a1). All formulations showed homogeneous macroscopic aspects without aggregation. The mean size of the nanocapsules measured by laser diffraction did not show difference among the samples (p = 0.241). Multi-wall nanocapsules (MLNC) showed a slight increase in the mean diameter and polydispersity index (PDI) measured by DLS, lower pH and an inversion in the zeta-potential (ξP) compared to LNCs. Conjugation test for anti-PECAM-1 showed 94.80% of efficiency. The mean diameter of the formulation had slightly increased from 160 nm (LCN-DHA) and 162 nm (MLNC-DHA) to 164 nm (MCMN-DHA-a1) indicating that the surface functionalization did not induce aggregation of the nanocapsules. Biological assays showed that the MCMN-DHA-a1 were uptaken by the HUVEC cells and did not decrease their viability. The surface-functionalized (anti- PECAM-1) metal-complex multi-wall nanocapsules containing DHA (MCMN-DHA-a1) can be considered adequate for pharmaceutical approaches.
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Anti-Inflamatórios/administração & dosagem , Aterosclerose/tratamento farmacológico , Ácidos Docosa-Hexaenoicos/administração & dosagem , Nanocápsulas/química , Molécula-1 de Adesão Celular Endotelial a Plaquetas/antagonistas & inibidores , Combinação de Medicamentos , Composição de Medicamentos/métodos , Células Endoteliais da Veia Umbilical Humana , Humanos , Lipídeos/química , Compostos Organometálicos/química , Tamanho da Partícula , Zinco/químicaRESUMO
Pequi is a Brazilian fruit used in folk medicine for pulmonary diseases treatment, but its oil presents bioavailability limitations. The use of nanocarriers can overcome this limitation. We developed nanoemulsions containing pequi oil (pequi-NE) and evaluated their effects in a lipopolysaccharide (LPS)-induced lung injury model. Free pequi oil or pequi-NE (20 mg/kg) was orally administered to A/J mice 16 and 4 h prior to intranasal LPS exposure, and the analyses were performed 24 h after LPS provocation. The physicochemical results revealed that pequi-NE comprised particles with mean diameter of 174-223 nm, low polydispersity index (0.11 ± 0.01), zeta potential of -7.13 ± 0.08 mV, and pH of 5.83 ± 0.12. In vivo evaluation showed that free pequi oil pretreatment reduced the influx of inflammatory cells into bronchoalveolar fluid (BALF), while pequi-NE completely abolished leukocyte accumulation. Moreover, pequi-NE, but not free pequi oil, reduced myeloperoxidase (MPO), TNF-α, IL-1ß, IL-6, MCP-1, and KC levels. Similar anti-inflammatory effects were observed when LPS-exposed animals were pre-treated with the nanoemulsion containing pequi or oleic acid. These results suggest that the use of nanoemulsions as carriers enhances the anti-inflammatory properties of oleic acid-containing pequi oil. Moreover, pequi's beneficial effect is likely due its high levels of oleic acid.
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Glioblastoma (GBM) is the most lethal form of brain tumor, being characterized by the rapid growth and invasion of the surrounding tissue. The current standard treatment for glioblastoma is surgery, followed by radiotherapy and concurrent chemotherapy, typically with temozolomide. Although extensive research has been carried out over the past years to develop a more effective therapeutic strategy for the treatment of GBM, efforts have not provided major improvements in terms of the overall survival of patients. Consequently, new therapeutic approaches are urgently needed. Overcoming the blood-brain barrier (BBB) is a major challenge in the development of therapies for central nervous system (CNS) disorders. In this context, the intranasal route of drug administration has been proposed as a non-invasive alternative route for directly targeting the CNS. This route of drug administration bypasses the BBB and reduces the systemic side effects. Recently, several formulations have been developed for further enhancing nose-to-brain transport, mainly with the use of nano-sized and nanostructured drug delivery systems. The focus of this review is to provide an overview of the strategies that have been developed for delivering anticancer compounds for the treatment of GBM while using nasal administration. In particular, the specific properties of nanomedicines proposed for nose-to-brain delivery will be critically evaluated. The preclinical and clinical data considered supporting the idea that nasal delivery of anticancer drugs may represent a breakthrough advancement in the fight against GBM.
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Antineoplásicos/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Glioblastoma/tratamento farmacológico , Mucosa Nasal/metabolismo , Administração Intranasal , Animais , Barreira Hematoencefálica/metabolismo , Encéfalo/efeitos dos fármacos , Sistemas de Liberação de Medicamentos/métodos , HumanosRESUMO
Zeaxanthin nanoparticles (Zea-NP) and zeaxanthin nanoemulsion (Zea-NE) were incorporated in yogurt. Control yogurt (CY), yogurt added of nanoparticles (Y-NP) and yogurt added of nanoemulsion (Y-NE) were evaluated weekly regarding pH, titratable acidity, color, textural parameters, viscosity and syneresis during 28â¯days. Zeaxanthin retention in Y-NP and Y-NE was also determined over storage. Sensory attributes and morphology were evaluated in all yogurt samples, and zeaxanthin bioaccessibility after in vitro digestion was analyzed in Y-NP and Y-NE after preparation. At the end of storage time, zeaxanthin retention was higher in Y-NP (22.31⯱â¯2.53%) than in Y-NE (16.84⯱â¯0.53%). Despite the lower firmness and viscosity observed in Y-NP, these changes were not sensory perceived. The bioaccessibility after in vitro digestion suggested that nanoencapsulation provided a controlled release of the carotenoid. Zea-NP can be incorporated in yogurt, allowing the dispersion of a hydrophobic compound in a hydrophilic matrix, providing stability.
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Carotenoides/química , Fenômenos Químicos , Nanopartículas/química , Paladar , Iogurte/análise , Zeaxantinas/química , ViscosidadeRESUMO
BACKGROUND: Resveratrol (RSV) has attracted interest as an alternative drug for the treatment of acute lung injury (ALI) and other pulmonary diseases, but its poor oral bioavailability is a limitation. In this study, we employed drug delivery nanotechnology to improve the stability, lung localization and efficacy of orally administered resveratrol to control lung damage leading to ALI. METHODS AND MATERIALS: RSV-loaded lipid-core nanocapsules (RSV-LNCs), prepared by interfacial deposition of biodegradable polymers, were given orally to A/J mice prior to lipopolysaccharide (LPS) intranasal instillation. Inflammatory changes, oxidative stress and lung tissue elastance were assessed 24 h after LPS challenge. RESULTS: RSV-LNCs (5 mg/kg), given 1, 4, 6 or 12 h but not 24 h before provocation, inhibited LPS-induced leukocyte accumulation in the bronchoalveolar fluid (BALF), whereas unloaded nanocapsules (ULNCs) or free RSV (5 mg/kg) were ineffective. RSV-LNCs (2.5-10 mg/kg) but not ULNCs or RSV improved lung function and prevented total leukocyte and neutrophil accumulation equally in both BALF and lung tissue when given 4 h before LPS challenge. Similar findings were seen concerning the generation of a range of pro-inflammatory cytokines such as IL-6, KC, MIP-1α, MIP-2, MCP-1 and RANTES in lung tissue. In addition, only RSV-LNCs inhibited MDA levels and SOD activity in parallel with blockade of the ERK and PI3K/Akt pathways following LPS provocation. CONCLUSION: Nanoformulation of RSV in biodegradable oil-core polymers is an effective strategy to improve the anti-ALI activity of RSV, suggesting that the modified-release formulation of this plant polyphenol may be of great value in clinical conditions associated with ALI and respiratory failure.
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Lesão Pulmonar Aguda/tratamento farmacológico , Lesão Pulmonar Aguda/enzimologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Nanocápsulas/química , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Resveratrol/administração & dosagem , Resveratrol/uso terapêutico , Transdução de Sinais , Lesão Pulmonar Aguda/complicações , Administração Oral , Animais , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Líquido da Lavagem Broncoalveolar , Citocinas/metabolismo , Mediadores da Inflamação/metabolismo , Lipopolissacarídeos , Pulmão/efeitos dos fármacos , Masculino , Camundongos Endogâmicos , Neutrófilos/efeitos dos fármacos , Neutrófilos/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Hipersensibilidade Respiratória/complicações , Hipersensibilidade Respiratória/patologia , Resveratrol/farmacologiaRESUMO
Linseed oil was nanoencapsulated with chia seed mucilage (CSM) as structuring material. Linseed oil nanoparticles (LO-NP) were evaluated regarding particle size distribution, zeta potential, pH, viscosity, encapsulation efficiency, loading capacity, morphology, FT-IR and thermal properties. Furthermore, the nanoparticles were spray-dried, and oxidative stability was evaluated during 28â¯days under storage at accelerated conditions (40⯰C). The bioaccessibility of spray dried nanoparticles (SP LO-NP) was also evaluated after in vitro digestion. Thereafter, SP LO-NP were utilized in the enrichment of orange juice, and physicochemical and sensory evaluation of pure orange juice and orange juice with SP LO-NP were evaluated. Nanoparticles in suspension presented a mean diameter of 356⯱â¯2.83â¯nm, zeta potential of -22.75⯱â¯3.89â¯mV and encapsulation efficiency of 52%. No significant differences regarding consumer acceptance were observed between pure orange juice and orange juice with SP LO-NP. The results suggest that CSM can be used as structuring material to nanoencapsulate hydrophobic compounds, allowing its solubility in foods with high water content. Furthermore, the SP LO-NP provided a good bioaccessibility to linseed oil after in vitro digestion, which represents an advantage to incorporate the nanoparticles in food.
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Citrus sinensis/química , Alimentos Fortificados , Sucos de Frutas e Vegetais , Óleo de Semente do Linho/química , Mucilagem Vegetal/química , Salvia/química , Nanotecnologia , Sementes/químicaRESUMO
Annona vepretorum is an endemic species of the Caatinga biome, known in Northeastern Brazil as "araticum" and/or "pinha da Caatinga". In the present study it was evaluated the neuropharmacological potential of the essential oil obtained from the leaves of Annona vepretorum, as well as of the inclusion complexes of oil obtained with cyclodextrin. Thus, were used neuropharmacological tests already consolidated in the literature like open-field, elevated plus maze, rota-rod, tail suspension test, thiopental-induced sleep test, among others. The acute treatment of essential oil (EO) has anxiolytic, sedative, antiepileptic and antidepressant effects. The anxiolytic and anticonvulsant effects seems to be related to the GABAergic system, probably in the receptor subtypes that mediate the effects of the benzodiazepines, to generate anxiolytic activity. The sedative effect seems to be involved with other signaling pathways. The antidepressant effect of EO seems to be related to its action on serotonergic receptors. It was verified that some behavioral parameters were improved with the oil complexed with ß-cyclodextrin, but this effect was not uniform for all the doses and tests used. Further studies are needed in order to use other options for drug delivery systems. Thus, the essential oil of Annona vepretorum is a promising agent with neurobiological activity and a potential target for drug discovery, since the natural products such as medicinal plants have been a source of new therapeutic proposals.
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Annona/química , Ansiolíticos/farmacologia , Anticonvulsivantes/farmacologia , Antidepressivos/farmacologia , Neurônios GABAérgicos/efeitos dos fármacos , Hipnóticos e Sedativos/farmacologia , Óleos Voláteis/farmacologia , Neurônios Serotoninérgicos/efeitos dos fármacos , Animais , Ansiedade/tratamento farmacológico , Comportamento Animal/efeitos dos fármacos , Masculino , Camundongos , Extratos Vegetais/farmacologia , Folhas de Planta/química , Plantas Medicinais/química , Transdução de Sinais/efeitos dos fármacosRESUMO
Drug delivery to the brain represents a challenge, especially in the therapy of central nervous system malignancies. Simvastatin (SVT), as with other statins, has shown potential anticancer properties that are difficult to exploit in the central nervous system (CNS). In the present work the physicoâ»chemical, mucoadhesive, and permeability-enhancing properties of simvastatin-loaded poly-ε-caprolactone nanocapsules coated with chitosan for nose-to-brain administration were investigated. Lipid-core nanocapsules coated with chitosan (LNCchit) of different molecular weight (MW) were prepared by a novel one-pot technique, and characterized for particle size, surface charge, particle number density, morphology, drug encapsulation efficiency, interaction between surface nanocapsules with mucin, drug release, and permeability across two nasal mucosa models. Results show that all formulations presented adequate particle sizes (below 220 nm), positive surface charge, narrow droplet size distribution (PDI < 0.2), and high encapsulation efficiency. Nanocapsules presented controlled drug release and mucoadhesive properties that are dependent on the MW of the coating chitosan. The results of permeation across the RPMI 2650 human nasal cell line evidenced that LNCchit increased the permeation of SVT. In particular, the amount of SVT that permeated after 4 hr for nanocapsules coated with low-MW chitosan, high-MW chitosan, and control SVT was 13.9 ± 0.8 µg, 9.2 ± 1.2 µg, and 1.4 ± 0.2 µg, respectively. These results were confirmed by SVT ex vivo permeation across rabbit nasal mucosa. This study highlighted the suitability of LNCchit as a promising strategy for the administration of simvastatin for a nose-to-brain approach for the therapy of brain tumors.
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OBJECTIVE: To evaluate, for the first time, the use of SCC4 cell monolayers as an alternative sublingual barrier model and study the influence of nanoencapsulation on carvedilol transport across SCC4 cell monolayers. SIGNIFICANCE: The sublingual cavity is an interesting route for administration of drugs with limited oral bioavailability due to hepatic first pass metabolism. By this route, the drug is directly absorbed into blood circulation. In this sense, mucoadhesive carvedilol-loaded nanocapsules (CAR-NC) were previously proposed for the administration of this drug by sublingual route. Carvedilol is used for cardiovascular diseases and suffers metabolism in liver when orally administrated. Nanoencapsulation of carvedilol controlled its permeation across porcine sublingual mucosa. METHODS: Carvedilol-loaded cationic nanocapsules were prepared by interfacial deposition of a preformed polymer. Drug permeation studies were carried out in Transwell® inserts. The integrity of cell monolayers after the drug transport was assessed by transepithelial electric resistance. Compatibility of the CAR-NC with the SCC4 cells was evaluated by the Sulforhodamine B assay. RESULTS: The drug permeated the cell monolayer by a controlled way when nanoencapsulated and this profile had a linear relation with those observed in porcine sublingual mucosa. The integrity of the cell monolayer was maintained after drug permeation and CAR-NC was no cytotoxic to SCC4 cells. CONCLUSION: Nanoencapsulated carvedilol permeated by a controlled and safe way by SCC4 cell monolayer. SCC4 cells monolayers may be used as in vitro model for sublingual drug transport studies in the development of novel formulations.
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Anti-Hipertensivos/síntese química , Anti-Hipertensivos/metabolismo , Carvedilol/síntese química , Carvedilol/metabolismo , Sistemas de Liberação de Medicamentos/métodos , Nanocápsulas/química , Administração Sublingual , Anti-Hipertensivos/administração & dosagem , Transporte Biológico/efeitos dos fármacos , Transporte Biológico/fisiologia , Carvedilol/administração & dosagem , Humanos , Nanocápsulas/administração & dosagem , Células Tumorais CultivadasRESUMO
Fungal resistance is the major problem related to fluconazole treatments. This study aims to develop innovative lipid core nanocapsules and nanostructured lipid carriers containing fluconazole, to study in vitro antifungal activity and to assess the possibility of resistance reversion in Candida albicans, C. glabrata, C. krusei, and C. tropicalis isolates. The action mechanism of nanoparticles was investigated through efflux pumps and scanning electron microscopy studies. The lipid core nanocapsules and nanostructured lipid carriers were prepared by interfacial deposition of preformed polymer and high-pressure homogenization methods, respectively. Both nanostructures presented sizes below 250 nm, SPAN < 1.6, negative zeta potential, pH slightly acid, high drug content and controlled drug release. The nanostructured lipid carriers were unable to reverse the fungal resistance. Lipid core nanoparticles displayed advantages such as a reduction in the effective dose of fluconazole and resistance reversion in all isolates tested - with multiple mechanisms of resistance. The main role of the supramolecular structure and the composition of the nanoparticles on antifungal mechanisms of action were discussed. The results achieved through this study have an impact on clinical therapy, with a potential application in the treatment of fungal infections caused by resistant isolates of Candida spp.
Assuntos
Antifúngicos/farmacologia , Candida/efeitos dos fármacos , Preparações de Ação Retardada/química , Farmacorresistência Fúngica/efeitos dos fármacos , Fluconazol/farmacologia , Proteínas Fúngicas/antagonistas & inibidores , Nanopartículas/química , Transportadores de Cassetes de Ligação de ATP/antagonistas & inibidores , Transportadores de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/metabolismo , Candida/genética , Candida/crescimento & desenvolvimento , Candida/metabolismo , Candida albicans/efeitos dos fármacos , Candida albicans/genética , Candida albicans/crescimento & desenvolvimento , Candida albicans/metabolismo , Candida glabrata/efeitos dos fármacos , Candida glabrata/genética , Candida glabrata/crescimento & desenvolvimento , Candida glabrata/metabolismo , Candida tropicalis/efeitos dos fármacos , Candida tropicalis/genética , Candida tropicalis/crescimento & desenvolvimento , Candida tropicalis/metabolismo , Caprilatos/química , Composição de Medicamentos/métodos , Farmacorresistência Fúngica/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Expressão Gênica , Genes MDR/efeitos dos fármacos , Hexoses/química , Concentração de Íons de Hidrogênio , Testes de Sensibilidade Microbiana , Nanopartículas/ultraestrutura , Palmitatos/química , Tamanho da Partícula , Triglicerídeos/química , Verapamil/farmacologiaRESUMO
The data presented here are related to the research paper entitled "PCL-b-P(MMA-co-DMAEMA)2 new triblock copolymer for novel pH-sensitive nanocapsules intended for drug delivery to tumors" by Franco et al. [1]. Characterization data of PCL-diol, macroinitiator Br-PCL-Br, homopolymers (PMMA and PDMAEMA) and copolymers (batch 1 and batch 2) analyzed by FTIR, SEC and NMR, as well as, characterization of PCL-NS formulation by laser diffraction and DLS analysis, initial nanocapsule formulations and 1C-NC and 2C-NC formulations, including hydrodynamic diameter at different pH media, and DMSO cytotoxicity.
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The industrial development of polymeric nanoparticle suspensions, as drug delivery systems, is limited due to the problems in maintaining stability of suspensions. In this work, a spray-drying technique was applied to dry nanocapsule and nanosphere suspensions prepared by nanoprecipitation of polyesters using SiO(2) as adjuvant. Powders obtained from nanocapsules presented stable drug recoveries and morphological characteristics after 5 months. For nanocapsules, nanostructures around 200 nm were observed by scanning electron microscopy (SEM) on the surface of microparticles of SiO(2), whereas for the nanosphere formulation, nanostructures with a reduced diameter (60-90 nm) were observed, despite the particle sizes of each original suspension being similar, when measured by photon correlation spectroscopy (PCS). In order to investigate the morphological aspects of nanocapsule and nanosphere powders, several nanosphere formulations were spray-dried using different concentrations of SiO(2) and a comparative study of the different colloidal systems (nanocapsules, nanospheres, nanoemulsion or nanodispersion) was carried out by PCS. SEM analyses showed that nanostructures with reduced diameter are formed independently of the adjuvant concentration. The dynamic properties of these systems allowed to suggest that the structure of the nanosphere particle (polymer, sorbitan monostearate and polysorbate 80) was a polymeric matrix dispersing the sorbitan monostearate which, when submitted to the spray-drying process in the presence of SiO(2), gave nanostructures presenting diameters around 80 nm covering the microparticles due to the release of lipophilic surfactant from the polymeric matrix.