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1.
Anal Chem ; 2020 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-32893620

RESUMO

An automated on-line isolation and fractionation system including controlling software was developed for selected nanosized biomacromolecules from human plasma by on-line coupled immunoaffinity chromatography-asymmetric flow field-flow fractionation (IAC-AsFlFFF). The on-line system was versatile, only different monoclonal antibodies, anti-apolipoprotein B-100, anti-CD9, or anti-CD61, were immobilized on monolithic disk columns for isolation of lipoproteins and extracellular vesicles (EVs). The platelet-derived CD61-positive EVs and CD9-positive EVs, isolated by IAC, were further fractionated by AsFlFFF to their size-based subpopulations (e.g., exomeres and exosomes) for further analysis. Field-emission scanning electron microscopy elucidated the morphology of the subpopulations, and 20 free amino acids and glucose in EV subpopulations were identified and quantified in the ng/mL range using hydrophilic interaction liquid chromatography-tandem mass spectrometry (HILIC-MS/MS). The study revealed that there were significant differences between EV origin and size-based subpopulations. The on-line coupled IAC-AsFlFFF system was successfully programmed for reliable execution of 10 sequential isolation and fractionation cycles (37-80 min per cycle) with minimal operator involvement, minimal sample losses, and contamination. The relative standard deviations (RSD) between the cycles for human plasma samples were 0.84-6.6%.

2.
ACS Appl Mater Interfaces ; 12(6): 6899-6909, 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-31967771

RESUMO

Heart tissue engineering is critical in the treatment of myocardial infarction, which may benefit from drug-releasing smart materials. In this study, we load a small molecule (3i-1000) in new biodegradable and conductive patches for application in infarcted myocardium. The composite patches consist of a biocompatible elastomer, poly(glycerol sebacate) (PGS), coupled with collagen type I, used to promote cell attachment. In addition, polypyrrole is incorporated because of its electrical conductivity and to induce cell signaling. Results from the in vitro experiments indicate a high density of cardiac myoblast cells attached on the patches, which stay viable for at least 1 month. The degradation of the patches does not show any cytotoxic effect, while 3i-1000 delivery induces cell proliferation. Conductive patches show high blood wettability and drug release, correlating with the rate of degradation of the PGS matrix. Together with the electrical conductivity and elongation characteristics, the developed biomaterial fits the mechanical, conductive, and biological demands required for cardiac treatment.

3.
Nanotechnology ; 2020 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-31978899

RESUMO

Amorphous SiO2-Nb2O5 nanolaminates and mixture films were grown by atomic layer deposition. The films were grown at 300 oC from Nb(OC2H5)5, Si2(NHC2H5)6, and O3 to thicknesses ranging from 13 to 130 nm. The niobium to silicon atomic ratio was varied in the range of 0.11-7.20. After optimizing the composition, resistive switching properties could be observed in the form of characteristic current-voltage behavior. Switching parameters in the conventional regime were well defined only in a SiO2:Nb2O5 mixture at certain, optimized, composition with Nb:Si atomic ratio of 0.13, whereas low-reading voltage measurements allowed recording memory effects in a wider composition range.

4.
ACS Omega ; 4(6): 11205-11214, 2019 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-31460221

RESUMO

Herein, we report an atomic layer deposition (ALD) process for Cu2O thin films using copper(II) acetate [Cu(OAc)2] and water vapor as precursors. This precursor combination enables the deposition of phase-pure, polycrystalline, and impurity-free Cu2O thin films at temperatures of 180-220 °C. The deposition of Cu(I) oxide films from a Cu(II) precursor without the use of a reducing agent is explained by the thermally induced reduction of Cu(OAc)2 to the volatile copper(I) acetate, CuOAc. In addition to the optimization of ALD process parameters and characterization of film properties, we studied the Cu2O films in the fabrication of photoconductor devices. Our proof-of-concept devices show that approximately 20 nm thick Cu2O films can be used for photodetection in the visible wavelength range and that the thin film photoconductors exhibit improved device characteristics in comparison to bulk Cu2O crystals.

5.
Chemistry ; 25(53): 12288-12293, 2019 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-31336013

RESUMO

HNO3 -oxidized carbon nanotubes catalyze oxidative dehydrogenative (ODH) carbon-carbon bond formation between electron-rich (hetero)aryls with O2 as a terminal oxidant. The recyclable carbocatalytic method provides a convenient and an operationally easy synthetic protocol for accessing various benzofused homodimers, biaryls, triphenylenes, and related benzofused heteroaryls that are highly useful frameworks for material chemistry applications. Carbonyls/quinones are the catalytically active site of the carbocatalyst as indicated by model compounds and titration experiments. Further investigations of the reaction mechanism with a combination of experimental and DFT methods support the competing nature of acid-catalyzed and radical cationic ODHs, and indicate that both mechanisms operate with the current material.

6.
Sci Rep ; 9(1): 4756, 2019 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-30894607

RESUMO

The dynamics of the origins and spread of farming are globally debated in anthropology and archaeology. Lately, numerous aDNA studies have turned the tide in favour of migrations, leaving only a few cases in Neolithic Europe where hunter-gatherers might have adopted agriculture. It is thus widely accepted that agriculture was expanding to its northern extreme in Sweden c. 4000 BC by migrating Funnel Beaker Culture (FBC) farmers. This was followed by intense contacts with local hunter-gatherers, leading to the development of the Pitted Ware Culture (PWC), who nonetheless relied on maritime prey. Here, we present archaeobotanical remains from Sweden and the Åland archipelago (Finland) showing that PWC used free-threshing barley and hulled and free-threshing wheat from c. 3300 BC. We suggest that these hunter-gatherers adopted cultivation from FBC farmers and brought it to islands beyond the 60th parallel north. Based on directly dated grains, land areas suitable for cultivation, and absence of signs of exchange with FBC in Sweden, we argue that PWC cultivated crops in Åland. While we have isotopic and lipid-biomarker proof that their main subsistence was still hunting/fishing/gathering, we argue small-scale cereal use was intended for ritual feasts, when cereal products could have been consumed with pork.

7.
ACS Appl Mater Interfaces ; 10(51): 44354-44367, 2018 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-30525379

RESUMO

Microfluidics technology is emerging as a promising strategy in improving the oral delivery of proteins and peptides. Herein, a multistage drug delivery system is proposed as a step forward in the development of noninvasive therapies. Undecylenic acid-modified thermally hydrocarbonized porous silicon (UnPSi) nanoparticles (NPs) were functionalized with the Fc fragment of immunoglobulin G for targeting purposes. Glucagon-like peptide-1 (GLP-1) was loaded into the NPs as a model antidiabetic drug. Fc-UnPSi NPs were coated with mucoadhesive chitosan and ultimately entrapped into a polymeric matrix with pH-responsive properties by microfluidic nanoprecipitation. The final formulation showed a controlled and narrow size distribution. The pH-responsive matrix remained intact in acidic conditions, dissolving only in intestinal pH, resulting in a sustained release of the payload. The NPs presented high cytocompatibility and increased levels of interaction with intestinal cells when functionalized with the Fc fragment, which was supported by the validation of the Fc-fragment integrity after conjugation to the NPs. Finally, the Fc-conjugated NPs showed augmented GLP-1 permeability in an intestinal in vitro model. These results highlight the potential of microfluidics as an advanced technique for the preparation of multistage platforms for oral administration. Moreover, this study provides new insights on the potential of the Fc receptor transcytotic capacity for the development of targeted therapies.


Assuntos
Quitosana , Antígenos de Histocompatibilidade Classe I/metabolismo , Hipoglicemiantes , Derivados da Hipromelose , Dispositivos Lab-On-A-Chip , Nanopartículas , Receptores Fc/metabolismo , Silício , Administração Oral , Células CACO-2 , Quitosana/química , Quitosana/farmacocinética , Quitosana/farmacologia , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacocinética , Preparações de Ação Retardada/farmacologia , Antígenos de Histocompatibilidade Classe I/química , Humanos , Hipoglicemiantes/química , Hipoglicemiantes/farmacocinética , Hipoglicemiantes/farmacologia , Derivados da Hipromelose/química , Derivados da Hipromelose/farmacocinética , Derivados da Hipromelose/farmacologia , Nanopartículas/química , Nanopartículas/uso terapêutico , Porosidade , Receptores Fc/química , Silício/química , Silício/farmacocinética , Silício/farmacologia
8.
Angew Chem Int Ed Engl ; 57(52): 17104-17109, 2018 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-30370970

RESUMO

Dissolution of elemental gold in organic solutions is a contemporary approach to lower the environmental burden associated with gold recycling. Herein, we describe fundamental studies on a highly efficient method for the dissolution of elemental Au that is based on DMF solutions containing pyridine-4-thiol (4-PSH) as a reactive ligand and hydrogen peroxide as an oxidant. Dissolution of Au proceeds through several elementary steps: isomerization of 4-PSH to pyridine-4-thione (4-PS), coordination with Au0 , and then oxidation of the Au0 thione species to AuI simultaneously with oxidation of free pyridine thione to elemental sulfur and further to sulfuric acid. The final dissolution product is a AuI complex bearing two 4-PS ligands and SO4 2- as a counterion. The ligand is crucial as it assists the oxidation process and stabilizes and solubilizes the formed Au cations.

9.
Biomaterials ; 185: 322-332, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30267958

RESUMO

Orally administrable drug delivery vehicles are developed to manage incurable inflammatory bowel disease (IBD), however, their therapeutic outcomes are compromised by the side effects of systemic drug exposure. Herein, we use hyaluronic acid functionalized porous silicon nanoparticle to bridge enzyme-responsive hydrogel and pH-responsive polymer, generating a hierarchical structured (nano-in-nano-in-micro) vehicle with programmed properties to fully and sequentially overcome the multiple obstacles for efficiently delivering drugs locally to inflamed sites of intestine. After oral administration, the pH-responsive matrix protects the embedded hybrid nanoparticles containing drug loaded hydrogels against the spatially variable physiological environments of the gastrointestinal tract until they reach the inflamed sites of intestine, preventing premature drug release. The negatively charged hybrid nanoparticles selectively target the inflamed sites of intestine, and gradually release drug in response to the microenvironment of inflamed intestine. Overall, the developed hierarchical structured and programmed vehicles load, protect, transport and release drugs locally to inflamed sites of intestine, contributing to superior therapeutic outcomes. Such strategy could also inspire the development of numerous hierarchical structured vehicles by other porous nanoparticles and stimuli-responsive materials for the local delivery of various drugs to treat plenty of inflammatory gastrointestinal diseases, including IBD, gastrointestinal cancers and viral infections.


Assuntos
Anti-Inflamatórios/administração & dosagem , Budesonida/administração & dosagem , Preparações de Ação Retardada/química , Doenças Inflamatórias Intestinais/tratamento farmacológico , Intestinos/efeitos dos fármacos , Silício/química , Administração Oral , Animais , Anti-Inflamatórios/farmacocinética , Anti-Inflamatórios/uso terapêutico , Budesonida/farmacocinética , Budesonida/uso terapêutico , Linhagem Celular , Sistemas de Liberação de Medicamentos , Humanos , Ácido Hialurônico/análogos & derivados , Concentração de Íons de Hidrogênio , Doenças Inflamatórias Intestinais/imunologia , Doenças Inflamatórias Intestinais/patologia , Intestinos/imunologia , Intestinos/patologia , Masculino , Camundongos Endogâmicos C57BL , Nanopartículas/química , Polímeros/química , Porosidade
10.
Small ; 14(27): e1800462, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29855134

RESUMO

The last decade has seen remarkable advances in the development of drug delivery systems as alternative to parenteral injection-based delivery of insulin. Neonatal Fc receptor (FcRn)-mediated transcytosis has been recently proposed as a strategy to increase the transport of drugs across the intestinal epithelium. FcRn-targeted nanoparticles (NPs) could hijack the FcRn transcytotic pathway and cross the epithelial cell layer. In this study, a novel nanoparticulate system for insulin delivery based on porous silicon NPs is proposed. After surface conjugation with albumin and loading with insulin, the NPs are encapsulated into a pH-responsive polymeric particle by nanoprecipitation. The developed NP formulation shows controlled size and homogeneous size distribution. Transmission electron microscopy (TEM) images show successful encapsulation of the NPs into pH-sensitive polymeric particles. No insulin release is detected at acidic conditions, but a controlled release profile is observed at intestinal pH. Toxicity studies show high compatibility of the NPs with intestinal cells. In vitro insulin permeation across the intestinal epithelium shows approximately fivefold increase when insulin is loaded into FcRn-targeted NPs. Overall, these FcRn-targeted NPs offer a toolbox in the development of targeted therapies for oral delivery of insulin.


Assuntos
Albuminas/química , Antígenos de Histocompatibilidade Classe I/química , Insulina/química , Nanopartículas/química , Polímeros/química , Receptores Fc/química , Silício/química , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Transmissão , Nanopartículas/ultraestrutura , Porosidade
11.
Anal Chim Acta ; 1024: 93-100, 2018 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-29776551

RESUMO

New chemical vapor reaction (CVR) and atomic layer deposition (ALD)-conversion methods were utilized for preparation of metal organic frameworks (MOFs) coatings of solid phase microextraction (SPME) Arrow for the first time. With simple, easy and convenient one-step reaction or conversion, four MOF coatings were made by suspend ALD iron oxide (Fe2O3) film or aluminum oxide (Al2O3) film above terephthalic acid (H2BDC) or trimesic acid (H3BTC) vapor. UIO-66 coating was made by zirconium (Zr)-BDC film in acetic acid vapor. As the first documented instance of all-gas phase synthesis of SPME Arrow coatings, preparation parameters including CVR/conversion time and temperature, acetic acid volume, and metal oxide film/metal-ligand films thickness were investigated. The optimal coatings exhibited crystalline structures, excellent uniformity, satisfactory thickness (2-7.5 µm), and high robustness (>80 times usage). To study the practical usefulness of the coatings for the extraction, several analytes with different chemical properties were tested. The Fe-BDC coating was found to be the most selective and sensitive for the determination of benzene ring contained compounds due to its highly hydrophobic surface and unsaturated metal site. UIO-66 coating was best for small polar, aromatic, and long chain polar compounds owing to its high porosity. The usefulness of new coatings were evaluated for gas chromatography-mass spectrometer (GC-MS) determination of several analytes, present in wastewater samples at three levels of concentration, and satisfactory results were achieved.

12.
Adv Mater ; 30(24): e1703393, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29024054

RESUMO

Herein, a novel nanohybrid based on porous silicon, gold nanoparticles (Au NPs), and acetalated dextran (DPSi/DAu@AcDEX) is reported to encapsulate and deliver one drug and increase the computer tomography (CT) signal for acute-liver-failure (ALF) theranostics. A microfluidic-assisted method is used to co-encapsulate different NPs in a single step. By alternating the surface properties of different NPs and by modulating the composition of the organic phase, both PSi and Au NPs are effectively encapsulated into the polymer matrix simultaneously, thus further achieving a multifunctional application. This system can be used to identify pathologically changes in the tissues and selectively deliver drugs to these sites. The loading of a therapeutic compound (XMU-MP-1) improves the drug solubility, precise, in situ drug delivery, and the drug-functioning time. In vivo results confirm a superior treatment effect and better compliance of this newly developed nanoformulation than free compound. This nanosystem plays a crucial role in targeting the lesion area, thus increasing the local drug concentration important for ALF reverse-effect. Moreover, the residence of Au NPs within the matrix further endows our system for CT-imaging. Altogether, these results support that this nanohybrid is a potential theranostic platform for ALF.


Assuntos
Nanopartículas , Dextranos , Ouro , Humanos , Falência Hepática Aguda , Regeneração Hepática , Silício , Nanomedicina Teranóstica
13.
Int J Pharm ; 536(1): 241-250, 2018 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-29195917

RESUMO

Bone tissue engineering is considered an alternative approach for conventional strategies available to treat bone defects. In this study, we have developed bone scaffolds composed of hydroxyapaptite (HAp), gelatin and mesoporous silica, all recognized as promising materials in bone tissue engineering due to favorable biocompatibility, osteoconductivity and drug delivery potential, respectively. These materials were coupled with conductive polypyrrole (PPy) polymer to create a novel bone scaffold for regenerative medicine. Conductive and non-conductive scaffolds were made by slurry casting method and loaded with a model antibiotic, vancomycin (VCM). Their properties were compared in different experiments in which scaffolds containing PPy showed good mechanical properties, higher protein adsorption and higher percentage of VCM release over a long duration of time compared to non-conductive scaffolds. Osteoblast cells were perfectly immersed into the gelatin matrix and remained viable for 14 days. Overall, new conductive composite bone scaffolds were created and the obtained results strongly verified the applicability of this conductive scaffold in drug delivery, encouraging its further development in tissue engineering applications.


Assuntos
Regeneração Óssea/efeitos dos fármacos , Polímeros/química , Pirróis/química , Dióxido de Silício/química , Vancomicina/química , Animais , Materiais Biocompatíveis/química , Osso e Ossos/efeitos dos fármacos , Células Cultivadas , Sistemas de Liberação de Medicamentos/métodos , Durapatita/química , Condutividade Elétrica , Gelatina/química , Camundongos , Osteoblastos/efeitos dos fármacos , Engenharia Tecidual/métodos , Tecidos Suporte
14.
ChemSusChem ; 10(24): 4879-4890, 2017 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-29112334

RESUMO

Ionic liquids are used to dewater a suspension of birch Kraft pulp cellulose nanofibrils (CNF) and as a medium for water-free topochemical modification of the nanocellulose (a process denoted as "WtF-Nano"). Acetylation was applied as a model reaction to investigate the degree of modification and scope of effective ionic liquid structures. Little difference in reactivity was observed when water was removed, after introduction of an ionic liquid or molecular co-solvent. However, the viscoelastic properties of the CNF suspended in two ionic liquids show that the more basic, but non-dissolving ionic liquid, allows for better solvation of the CNF. Vibrio fischeri bacterial tests show that all ionic liquids in this study were harmless. Scanning electron microscopy and wide-angle X-ray scattering on regenerated samples show that the acetylated CNF is still in a fibrillar form. 1 D and 2 D NMR analyses, after direct dissolution in a novel ionic liquid electrolyte solution, indicate that both cellulose and residual xylan on the surface of the nanofibrils reacts to give acetate esters.

15.
Nanomedicine (Lond) ; 12(21): 2581-2596, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28960138

RESUMO

AIM: To carboxylate kraft lignin toward the functionalization of carboxylated lignin nanoparticles (CLNPs) with a block copolymer made of PEG, poly(histidine) and a cell-penetrating peptide and then evaluate the chemotherapeutic potential of the innovative nanoparticles. MATERIALS & METHODS: The produced nanoparticles were characterized and evaluated in vitro for stability and biocompatibility and the drug release profiles and antiproliferative effect were also assessed. RESULTS: The prepared CLNPs showed spherical shape and good size distribution, good stability in physiological media and low cytotoxicity in all the tested cell lines. A poorly water-soluble cytotoxic agent was successfully loaded into the CLNPs, improving its release profiles in a pH-sensitive manner and showing an enhanced antiproliferative effect in the different cancer cells compared with a normal endothelial cell line. CONCLUSION: The resulting CLNPs are promising candidates for anticancer therapy.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Portadores de Fármacos/química , Lignina/química , Nanopartículas/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Peptídeos Penetradores de Células/química , Liberação Controlada de Fármacos , Histidina/química , Humanos , Concentração de Íons de Hidrogênio , Teste de Materiais , Tamanho da Partícula , Polietilenoglicóis/química , Propriedades de Superfície
16.
Int J Pharm ; 531(1): 47-58, 2017 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-28802795

RESUMO

We introduce atomic layer deposition (ALD) as a novel method for the ultrathin coating (nanolayering) of minitablets. The effects of ALD coating on the tablet characteristics and taste masking were investigated and compared with the established coating method. Minitablets containing bitter tasting denatonium benzoate were coated by ALD using three different TiO2 nanolayer thicknesses (number of deposition cycles). The established coating of minitablets was performed in a laboratory-scale fluidized-bed apparatus using four concentration levels of aqueous Eudragit® E coating polymer. The coated minitablets were studied with respect to the surface morphology, taste masking capacity, in vitro disintegration and dissolution, mechanical properties, and uniformity of content. The ALD thin coating resulted in minimal increase in the dimensions and weight of minitablets in comparison to original tablet cores. Surprisingly, ALD coating with TiO2 nanolayers decreased the mechanical strength, and accelerated the in vitro disintegration of minitablets. Unlike previous studies, the studied levels of TiO2 nanolayers on tablets were also inadequate for effective taste masking. In summary, ALD permits a simple and rapid method for the ultrathin coating (nanolayering) of minitablets, and provides nanoscale-range TiO2 coatings on porous minitablets. More research, however, is needed to clarify its potential in tablet taste masking applications.


Assuntos
Comprimidos , Tecnologia Farmacêutica/métodos , Ácidos Polimetacrílicos , Solubilidade , Paladar , Titânio
17.
Small ; 13(33)2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28714245

RESUMO

Ischemic heart disease is the leading cause of death globally. Severe myocardial ischemia results in a massive loss of myocytes and acute myocardial infarction, the endocardium being the most vulnerable region. At present, current therapeutic lines only ameliorate modestly the quality of life of these patients. Here, an engineered nanocarrier is reported for targeted drug delivery into the endocardial layer of the left ventricle for cardiac repair. Biodegradable porous silicon (PSi) nanoparticles are functionalized with atrial natriuretic peptide (ANP), which is known to be expressed predominantly in the endocardium of the failing heart. The ANP-PSi nanoparticles exhibit improved colloidal stability and enhanced cellular interactions with cardiomyocytes and non-myocytes with minimal toxicity. After confirmation of good retention of the radioisotope 111-Indium in relevant physiological buffers over 4 h, in vivo single-photon emission computed tomography (SPECT/CT) imaging and autoradiography demonstrate increased accumulation of ANP-PSi nanoparticles in the ischemic heart, particularly in the endocardial layer of the left ventricle. Moreover, ANP-PSi nanoparticles loaded with a novel cardioprotective small molecule attenuate hypertrophic signaling in the endocardium, demonstrating cardioprotective potential. These results provide unique insights into the development of nanotherapies targeted to the injured region of the myocardium.


Assuntos
Endocárdio/patologia , Nanopartículas/química , Transdução de Sinais , Animais , Sobrevivência Celular , Fenômenos Químicos , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Hidrodinâmica , Hipertrofia , Masculino , Nanopartículas/ultraestrutura , Ratos Wistar , Propriedades de Superfície , Distribuição Tecidual
18.
Adv Healthc Mater ; 6(20)2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28714596

RESUMO

An advanced oral drug delivery system that can effectively deliver drugs with poor oral bioavailability is strongly desirable. Herein, a multifunctional nano-in-micro structured composite is developed by encapsulation of the mucoadhesive poly(methyl vinyl ether-co-maleic acid) modified halloysite nanotubes (HNTs) with the pH-responsive hydroxypropyl methylcellulose acetate succinate by the microfluidics to control the drug release, increase cell-particle interaction, and improve drug absorption. The microparticles show spherical shape, homogeneous particle size distribution (58 ± 1 µm), and pH-responsive dissolution behavior at pH > 6, and they prevent the premature release of curcumin in simulated pH conditions of the stomach and immediately release the curcumin in simulated pH conditions of the small intestine. The surface modification of HNT with mucoadhesive poly(methyl vinyl ether-co-maleic acid) significantly enhances its interactions with the intestinal Caco-2/HT29-MTX cells and the mouse small intestines, and increases the permeability of curcumin across the co-cultured Caco-2/HT29-MTX cell monolayers by about 13 times compared to the free curcumin. Therefore, the developed multifunctional nanotube-mucoadhesive poly(methyl vinyl ether-co-maleic acid)@hydroxypropyl methylcellulose acetate succinate composite is a promising oral drug delivery system for drugs with poor oral bioavailability.


Assuntos
Portadores de Fármacos/química , Maleatos/química , Éteres Metílicos/química , Metilcelulose/análogos & derivados , Nanotubos/química , Polivinil/química , Administração Oral , Animais , Células CACO-2 , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Curcumina/química , Curcumina/metabolismo , Curcumina/farmacologia , Portadores de Fármacos/farmacologia , Liberação Controlada de Fármacos , Células HT29 , Humanos , Concentração de Íons de Hidrogênio , Intestino Delgado/metabolismo , Metilcelulose/química , Camundongos , Tamanho da Partícula , Permeabilidade/efeitos dos fármacos
19.
Nanomedicine (Lond) ; 12(12): 1401-1420, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28524813

RESUMO

AIM: To evaluate the chemotherapeutic potential of a novel multifunctional nanocomposite encapsulating both porous silicon (PSi) and gold (Au) nanoparticles in a polymeric nanocomplex. MATERIALS & METHODS: The nanocomposite was physicochemically characterized and evaluated in vitro for biocompatibility, cellular internalization, endosomolytic properties, cytoplasmatic drug delivery and chemotherapeutic efficacy. RESULTS: The nanocomposites were successfully produced and exhibited adequate physicochemical properties and superior in vitro cyto- and hemocompatibilities. The encapsulation of PSi nanoparticles in the nanocomplexes significantly enhanced their cellular internalization and enabled their endosomal escape, resulting in the efficient cytoplasmic delivery of these nanosystems. Sorafenib-loaded nanocomposites showed a potent in vitro antiproliferative effect on MDA-MB-231 breast cancer cells. CONCLUSION: The multifunctional nanocomposite herein presented exhibits great potential as a chemotherapeutic nanoplatform.

20.
Int J Pharm ; 525(1): 160-174, 2017 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-28432020

RESUMO

Active pharmaceutical ingredients (APIs) are predominantly organic solid powders. Due to their bulk properties many APIs require processing to improve pharmaceutical formulation and manufacturing in the preparation for various drug dosage forms. Improved powder flow and protection of the APIs are often anticipated characteristics in pharmaceutical manufacturing. In this work, we have modified acetaminophen particles with atomic layer deposition (ALD) by conformal nanometer scale coatings in a one-step coating process. According to the results, ALD, utilizing common chemistries for Al2O3, TiO2 and ZnO, is shown to be a promising coating method for solid pharmaceutical powders. Acetaminophen does not undergo degradation during the ALD coating process and maintains its stable polymorphic structure. Acetaminophen with nanometer scale ALD coatings shows slowed drug release. ALD TiO2 coated acetaminophen particles show cytocompatibility whereas those coated with thicker ZnO coatings exhibit the most cytotoxicity among the ALD materials under study when assessed in vitro by their effect on intestinal Caco-2 cells.


Assuntos
Acetaminofen/química , Excipientes/química , Nanotecnologia , Células CACO-2 , Humanos , Pós , Propriedades de Superfície
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