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1.
J Photochem Photobiol B ; 202: 111715, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31790882

RESUMO

Biomimetic gold nanoparticles of biological origin have created a significant impact on the field of biomedicine due to the great expectations of its applications. Because of this, the influences of biomimetic gold nanoparticles have been immensely studied, targeting various cancer cells. However, the impact of biomimetic gold nanoparticles against normal non-cancerous cells is scanty, which impose several limitations in their utility. Taking this as a challenge, we in this study report the biomimetic gold nanoparticles from marine seaweed Gelidium pusillum (G. pusillum) to evaluate its cytotoxic and biocompatible ability evidenced by fluorescence-based assays in cultured cells. The gold nanoparticles obtained in the study were spherical shaped with a mean diameter of 12 ± 4.2 nm. The seaweed extract plays a crucial role in stabilizing the gold nanoparticles to avoid aggregation and coalescence. At an IC50 concentration of 43.09 ± 1.6 µgmL-1, the biomimetic gold nanoparticles were found to be toxic to cancerous cells (MDA-MB-231). Whereas, biomimetic gold nanoparticles exhibit significant biocompatibility with human embryonic kidney cells even at a higher concentration of 150 µgmL-1. The morphological based fluorescence assays confirmed the ability of biomimetic gold nanoparticles in inducing apoptosis and thereby kills cancer cells. Altogether, the gold nanoparticles were safe to normal cells and did not show a significant impact. Hence, the novel biomimetic gold nanoparticles hold potential as multifaceted agent and can further be taken up to various biomedical applications.


Assuntos
Materiais Biocompatíveis/química , Ouro/química , Nanopartículas Metálicas/química , Apoptose/efeitos dos fármacos , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/farmacologia , Linhagem Celular Tumoral , Química Verde , Células HEK293 , Humanos , Nanopartículas Metálicas/toxicidade , Tamanho da Partícula , Extratos Vegetais/química , Alga Marinha/química , Alga Marinha/metabolismo
2.
Chemistry ; 26(5): 1091-1102, 2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-31743947

RESUMO

Spin-orbit charge-transfer intersystem crossing (SOCT-ISC) is useful for the preparation of heavy atom-free triplet photosensitisers (PSs). Herein, a series of perylene-Bodipy compact electron donor/acceptor dyads showing efficient SOCT-ISC is prepared. The photophysical properties of the dyads were studied with steady-state and time-resolved spectroscopies. Efficient triplet state formation (quantum yield ΦT =60 %) was observed, with a triplet state lifetime (τT =436 µs) much longer than that accessed with the conventional heavy atom effect (τT =62 µs). The SOCT-ISC mechanism was unambiguously confirmed by direct excitation of the charge transfer (CT) absorption band by using nanosecond transient absorption spectroscopy and time-resolved electron paramagnetic resonance (TREPR) spectroscopy. The factors affecting the SOCT-ISC efficiency include the geometry, the potential energy surface of the torsion, the spin density for the atoms of the linker, solvent polarity, and the energy matching of the 1 CT/3 LE states. Remarkably, these heavy atom-free triplet PSs were demonstrated as a new type of efficient photodynamic therapy (PDT) reagents (phototoxicity, EC50 =75 nm), with a negligible dark toxicity (EC50 =78.1 µm) compared with the conventional heavy atom PSs (dark toxicity, EC50 =6.0 µm, light toxicity, EC50 =4.0 nm). This study provides in-depth understanding of the SOCT-ISC, unveils the design principles of triplet PSs based on SOCT-ISC, and underlines their application as a new generation of potent PDT reagents.


Assuntos
Materiais Biocompatíveis/química , Fármacos Fotossensibilizantes/química , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Desenho de Drogas , Espectroscopia de Ressonância de Spin Eletrônica , Elétrons , Células HeLa , Humanos , Fármacos Fotossensibilizantes/síntese química , Fármacos Fotossensibilizantes/farmacologia , Teoria Quântica , Oxigênio Singlete/química , Oxigênio Singlete/metabolismo , Solventes/química , Marcadores de Spin
3.
Chem Commun (Camb) ; 55(87): 13112-13115, 2019 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-31612874

RESUMO

Biocompatible chemical cross-linked hybrid polyethylene glycol-based hydrogels were obtained from a sol-gel process using bis-silylated molecular precursors in biocompatible conditions. This soft procedure (pH = 7.4, at 25 °C), allows the production of microgels by microfluidics and easy encapsulation of a model protein (Bovin Serum Albumine, BSA).


Assuntos
Materiais Biocompatíveis/síntese química , Hidrogéis/síntese química , Microfluídica , Polietilenoglicóis/síntese química , Soroalbumina Bovina/química , Animais , Materiais Biocompatíveis/química , Bovinos , Géis/química , Hidrogéis/química , Estrutura Molecular , Tamanho da Partícula , Polietilenoglicóis/química , Propriedades de Superfície
4.
Carbohydr Polym ; 225: 115210, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31521316

RESUMO

Macromolecular drugs, such as proteins and peptides, are lately readily available and used in the treatment of diseases including diabetes and cancer, as well as in therapies such as gene therapy, wound dressing, and tissue engineering. However, the bioavailability, the extent and the rate at which these drugs reach the target tissue are highly dependent on the carrier and on the route of administration. Among the multitude of biocompatible polymers used to design vehicles for macromolecular drugs, polysaccharides are preferred due to their mucoadhesive, antimicrobial, and anti-inflammatory properties. This review aims to give an overview on the evolution of polysaccharide-based vehicles recommended in the controlled delivery of proteins and peptides, mainly reported in the last five years. Both physically and chemically cross-linked drug delivery systems are presented such as: porous hydrogels, polyelectrolyte complexes and layer-by-layer thin films. Even if the pharmaceutical formulations for oral administration of proteins and peptides are preferred, other friendly routes are discussed in this review, such as transdermal delivery.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Hidrogéis , Peptídeos/farmacocinética , Polímeros , Polissacarídeos , Proteínas/farmacocinética , Animais , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/uso terapêutico , Disponibilidade Biológica , Diabetes Mellitus/tratamento farmacológico , Humanos , Hidrogéis/química , Hidrogéis/uso terapêutico , Substâncias Macromoleculares/farmacocinética , Neoplasias/tratamento farmacológico , Polímeros/química , Polímeros/uso terapêutico , Polissacarídeos/química , Polissacarídeos/uso terapêutico , Engenharia Tecidual
5.
Chem Commun (Camb) ; 55(82): 12360-12363, 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31559989

RESUMO

Photoactive nano TiO2 particles with fluorescent properties have attracted great attention because of their potential applications in photodynamic therapy. Herein we report first a simple method to prepare water soluble fluorescent nano titanium oxide particles from titanium-oxo-clusters (TOCs). The nano material was characterized as an aggregate of titanium-oxo-clusters, which can be used directly in aqueous systems for investigations in biomedical fields.


Assuntos
Materiais Biocompatíveis/síntese química , Corantes Fluorescentes/síntese química , Nanoestruturas/química , Titânio/química , Materiais Biocompatíveis/química , Pesquisa Biomédica , Corantes Fluorescentes/química , Tamanho da Partícula , Fotoquimioterapia , Solubilidade , Propriedades de Superfície
6.
Mater Sci Eng C Mater Biol Appl ; 105: 109912, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31546348

RESUMO

In this study, a simple and facile strategy was developed for the synthesis of novel hydroxyapatite (HA)/nanostructured monticellite ceramic composites by mechanical method. X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive x-ray spectroscopy (EDS) were used to peruse the phase structure, and morphology of soaked ceramic composites in simulated body fluid (SBF). The in vitro bioactivity of HA-based ceramic composites with nanostructured monticellite ranging from 0 to 50 wt% was evaluated via investigating the formation ability of bone-like calcium phosphates in SBF and the effect of obtained extracts from composites dissolution on osteoblast-like G-292 cell line. Moreover, In vitro cytocompatibility of the HA/monticellite ceramic composites was investigated by MTT, cell growth & adhesion and alkaline phosphatase (ALP) activity assays, and quantitative real-time PCR analysis. The results showed that HA/nanostructured monticellite ceramic composites could induce apatite formation in SBF. The cell proliferation and growth exposed to ceramic composites extracts were significantly stimulated and promoted at a certain concentration range compared to control for various time periods of cell culture. The optimized composite extract enhanced considerably gene expression of G-292 type X collagen (COLX) at different days. Also, G-292 cells were spread and adhered well on the ceramic composite disc. Furthermore, ALP activity of G-292 cells exposed to ceramic composites extracts was dramatically enhanced in comparison with pure HA extract (as control) at different concentrations for various time periods of cell culture. The results suggest that the optimized HA/nanostructured monticellite composite is promising biomaterial for clinical applications such as orthopedic and dentistry.


Assuntos
Materiais Biocompatíveis/síntese química , Tecnologia Biomédica/métodos , Durapatita/síntese química , Nanoestruturas/química , Ácido Silícico/síntese química , Fosfatase Alcalina/metabolismo , Animais , Materiais Biocompatíveis/química , Adesão Celular , Linhagem Celular , Proliferação de Células , Cerâmica/química , Colágeno Tipo X/metabolismo , Corrosão , Durapatita/química , Humanos , Osteoblastos/citologia , Osteogênese , Tamanho da Partícula , Ácido Silícico/química , Difração de Raios X
7.
Biomed Mater Eng ; 30(4): 375-386, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31476142

RESUMO

BACKGROUND: The scaffold for head and neck reconstruction needs mechanical strength to maintain specific forms. Hydroxyapatite (HA) enhances the mechanical strength of hydrogel and is routinely used for cartilage regeneration. However, there is a demand for hydroxyapatite that controls chondrogenic cell behavior. OBJECTIVE: Our aim was to regulate HA morphology through a hydrothermal process using organic acid and enhance chondrocyte proliferation and differentiation using shaped-regulated HA. METHODS: HA was synthesized from dodecanedioic acid (DD:HA) and oleic acid (OA:HA) by a hydrothermal method and then coated onto glass plates. Surface properties of the samples were compared by various techniques. Surface roughness and contact angles were calculated. Proliferation and differentiation of chondrogenic cells were measured by MTT assays and Alcian Blue staining, respectively, after various incubation periods. RESULTS: The morphological structures of DD:HA and OA:HA were different; however, the crystallinity and chemical structures were similar. Surface roughness and hydrophilic behavior were higher on DD:HA. DD:HA enhanced chondrogenic cell proliferation over time. The differentiation of ATDC5 cells was also increased on the DD:HA surface compared with those in other groups. CONCLUSIONS: DD:HA enhanced cell viability to a greater extent than OA:HA did, indicating its excellent potential as an inorganic material compatible with chondrocyte regeneration.


Assuntos
Materiais Biocompatíveis/química , Condrócitos/citologia , Condrogênese , Ácidos Dicarboxílicos/química , Durapatita/química , Animais , Materiais Biocompatíveis/síntese química , Diferenciação Celular , Linhagem Celular , Proliferação de Células , Ácidos Dicarboxílicos/síntese química , Durapatita/síntese química , Camundongos , Propriedades de Superfície , Tecidos Suporte/química
8.
Mater Sci Eng C Mater Biol Appl ; 104: 109845, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31500034

RESUMO

The facile preparation of macroporous, super water absorbing, biocompatible hydrogels of chitosan involving the hydrothermal reaction of a mixture of chitosan (CH), succinic acid (SA) and urea (UR), all of which are sustainable materials, is reported. The structure of the dry CHSAUR was ascertained by CP MAS-SS NMR spectroscopy, Fourier transform infrared (FTIR) spectroscopy, powder x-ray diffraction analysis (PXRD), and thermogravimetric analysis (TGA). The principle role of UR in the synthesis was identified as the source of ammonia, which increased the pH of the acidic chitosan solution with reaction time, leading to the formation of the insoluble hydrogel of chitosan accompanied by the formation of pores of different sizes and volumes. In addition, a small fraction of urea participated in chemical reaction with the primary hydroxyl groups in the sixth position of the glucosamine repeat units of chitosan resulting in carbamate linkages. The as-prepared hydrogel, following workup and methanol extraction, was found to be chitosan crosslinked with succinic acid through electrostatic interaction. It was macroporous with percentage porosity varying between 49.4% to 64.2%. It also exhibited different extents of water uptake with the maximum of 760 ±â€¯20 g/g being for the one prepared with the weight ratio of 1: 4: 4 of chitosan: succinic acid: urea. The absorption of water is found to arise out of the porosity as well as presence of water attracting chitosan ammonium cation-succinate electrovalent bonds that are formed by the reaction between SA and ammonium cation of the chitosan backbone. The absorption of saline water was relatively poor suggesting that the saline water absorption might be arising largely due to the presence of micropores and specific interaction. The hydrogels exhibited Herschel-Bulkley rheological behavior. The extraction of CHSAUR with 0.1 N NaOH in methanol resulted in the removal of the physical crosslinks, consisting of succinate anions; the presence of chitosan with porous morphology was confirmed additionally by copper (+2) adsorption. In contrast to the widely reported method of preparing microporous chitosan scaffold of cylindrical shape that takes several days to a week, the present method offers a simple means of preparing macroporous chitosan of any shape and size in very large scale with soft foam-like morphology. With its biocompatibility towards mouse fibroblast cells it could find applications in drug delivery, biodegradable super water absorbency and haemostatic applications.


Assuntos
Materiais Biocompatíveis/síntese química , Quitosana/química , Hidrogéis/síntese química , Temperatura Ambiente , Ureia/química , Água/química , Células 3T3-L1 , Animais , Sobrevivência Celular , Reagentes para Ligações Cruzadas/química , Hidrogéis/química , Espectroscopia de Ressonância Magnética , Camundongos , Porosidade , Reologia , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria , Viscosidade , Difração de Raios X , Microtomografia por Raio-X
9.
J Mater Sci Mater Med ; 30(8): 92, 2019 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-31388767

RESUMO

Having similar properties with natural bone, has made porous NiTi shape memory alloy (SMA) a promising material for biomedical applications. In this study porous NiTi SMA has synthesized with 30 and 40 vol.% green porosity by self propagating high temperature synthesis (SHS) from elemental Ni and Ti powders. After synthesizing, the average porosity of specimens reached to 36.8 and 49.8% for green compacts with 30 and 40 vol.% of green porosity, respectively. Combustion products were characterized by XRD, SEM, EDS and electrochemical polarization test. Although desired B2 (NiTi) phase was the dominant phase, other phases like Ti2Ni, Ni3Ti and Ni4Ti3 are found. Electrochemical polarization analysis in simulated body fluids (SBF) shows that, synthesized porous NiTi has better corrosion resistance than solid one and hydroxy apatite coating on porous NiTi worsen electrochemical corrosion resistance which is because of bioactive behavior of hydroxy apatite.


Assuntos
Ligas/síntese química , Materiais Biocompatíveis/síntese química , Temperatura Alta , Microtecnologia/métodos , Níquel/química , Polimerização , Titânio/química , Ligas/química , Materiais Biocompatíveis/química , Teste de Materiais , Microscopia Eletrônica de Varredura , Porosidade , Pós/síntese química , Pós/química , Espectrometria por Raios X , Propriedades de Superfície , Difração de Raios X
10.
Photochem Photobiol Sci ; 18(10): 2442-2448, 2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31384873

RESUMO

In recent years, several drugs have become relatively easy to obtain with the rapid development of the economy and improvement in people's living standards. However, pathogenic bacteria have evolved strains that are resistant to certain drugs, such as antibiotics. Peptides are generally considered to be safe, have high tolerance to drugs, and are easy to manufacture. However, peptides are easily decomposed in complex biological environments. To solve this problem, many studies have modified peptides on the surface of nanomaterials to increase their functionality, biocompatibility, and stability. Meanwhile, nanomaterials have exhibited good absorption of near-infrared (NIR) light. When the NIR laser is focused on nanomaterials, photons are absorbed and the energy of the photons is converted into heat. Low-toxicity NRC03 peptide-conjugated dopamine/nano-reduced-graphene oxide (NRC03-DA/nRGO) nanomaterials are synthesized in this study for antibacterial testing using photothermal technology. The strains used in this study were Gram-positive Staphylococcus aureus (S. aureus). Our results indicated that the synthesized NRC03-DA/nRGO exhibits good absorption of NIR light and high photothermal conversion efficiency. Moreover, the synthesized NRC03-DA/nRGO inhibits the growth and survival of S. aureus. When the NRC03 peptide is modified on the surface of DA/nRGO, its biological stability is improved and the photothermal effect generated by NIR light produces additive effects, thereby indicating potential antibacterial applications.


Assuntos
Antibacterianos/farmacologia , Dopamina/química , Grafite/química , Nanoestruturas/química , Peptídeos/química , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos/química , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Raios Infravermelhos
11.
J Mater Sci Mater Med ; 30(8): 96, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31414231

RESUMO

Critical size bone defects that do not heal spontaneously are among the major reasons for the disability in majority of people with locomotor disabilities. Tissue engineering has become a promising approach for repairing such large tissue injuries including critical size bone defects. Three-dimension (3D) porous scaffolds based on piezoelectric polymers like poly(vinylidene fluoride-trifluoroethylene) (P(VDF-TrFE)) have received a lot of attention in bone tissue engineering due to their favorable osteogenic properties. Owing to the favourable redox properties, titanium dioxide (TiO2) nanostructures have gained a great deal of attention in bone tissue engineering. In this paper, tissue engineering scaffolds based on P(VDF-TrFE) loaded with TiO2 nanowires (TNW) were developed and evaluated for bone tissue engineering. Wet-chemical method was used for the synthesis of TNW. Obtained TNW were thoroughly characterized for the physicochemical and morphological properties using techniques such as X-Ray diffraction (XRD) analysis and transmission electron microscopy (TEM). Electrospinning was used to produce TNW incorporated P(VDF-TrFE) scaffolds. Developed scaffolds were characterized by state of art techniques such as Scanning Electron Microscopy (SEM), XRD and Differential scanning calorimetry (DSC) analyses. TEM analysis revealed that the obtained TiO2 nanostructures possess nanofibrous morphology with an average diameter of 26 ± 4 nm. Results of characterization of nanocomposite scaffolds confirmed the effective loading of TNW in P(VDF-TrFE) matrix. Fabricated P(VDF-TrFE)/TNW scaffolds possessed good mechanical strength and cytocompatibility. Osteoblast like cells showed higher adhesion and proliferation on the nanocomposite scaffolds. This investigation revealed that the developed P(VDF-TrFE) scaffolds containing TNW can be used as potential scaffolds for bone tissue engineering applications.


Assuntos
Osso e Ossos/citologia , Nanofios/química , Polivinil/química , Engenharia Tecidual , Tecidos Suporte/química , Titânio/química , Compostos de Vinila/química , Animais , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/fisiologia , Hidrocarbonetos Fluorados/química , Teste de Materiais , Camundongos , Nanocompostos/química , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Osteoblastos/fisiologia , Ratos , Engenharia Tecidual/instrumentação , Engenharia Tecidual/métodos
12.
J Mater Sci Mater Med ; 30(9): 98, 2019 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-31440844

RESUMO

Calcium magnesium silicate glasses could be suggested for the synthesis of scaffolds for hard tissue regeneration, as they present a high residual glassy phase, high hardness values and hydroxyapatite-forming ability. The use of trace elements in the human body, such as Cu, could improve the biological performance of such glasses, as Cu is known to play a significant role in angiogenesis. Nano-bioceramics are preferable compared to their micro-scale counterparts, because of their increased surface area, which improves both mechanical properties and apatite-forming ability due to the increased nucleation sites provided, their high diffusion rates, reduced sintering time or temperature, and high mechanical properties. The aim of the present work was the evaluation of the effect of different ratios of Ethanol/TEOS and total amount of the inserted ammonia to the particle size, morphology and bioactive, hemolytic and antibacterial behavior of nanoparticles in the quaternary system SiO2-CaO-MgO-CuO. Different ratios of Ethanol/TEOS and ammonia amount affected the size and morphology of bioactive nanopowders. The optimum materials were synthesized with the highest ethanol/TEOS ratio and ammonia amount as verified by the enhanced apatite-forming ability and antibacterial and non-hemolytic properties.


Assuntos
Amônia/farmacologia , Cálcio/química , Cobre/química , Etanol/farmacologia , Silicatos/síntese química , Apatitas/síntese química , Apatitas/química , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/química , Cerâmica/síntese química , Cerâmica/química , Relação Dose-Resposta a Droga , Eritrócitos/citologia , Eritrócitos/efeitos dos fármacos , Etanol/química , Vidro/química , Humanos , Teste de Materiais , Nanocompostos/química , Silicatos/química , Silicatos/farmacologia , Dióxido de Silício/química , Propriedades de Superfície/efeitos dos fármacos
13.
Artif Cells Nanomed Biotechnol ; 47(1): 3524-3539, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31437011

RESUMO

The nervous system is known as a crucial part of the body and derangement in this system can cause potentially lethal consequences or serious side effects. Unfortunately, the nervous system is unable to rehabilitate damaged regions following seriously debilitating disorders such as stroke, spinal cord injury and brain trauma which, in turn, lead to the reduction of quality of life for the patient. Major challenges in restoring the damaged nervous system are low regenerative capacity and the complexity of physiology system. Synthetic polymeric biomaterials with outstanding properties such as excellent biocompatibility and non-immunogenicity find a wide range of applications in biomedical fields especially neural implants and nerve tissue engineering scaffolds. Despite these advancements, tailoring polymeric biomaterials for design of a desired scaffold is fundamental issue that needs tremendous attention to promote the therapeutic benefits and minimize adverse effects. This review aims to (i) describe the nervous system and related injuries. Then, (ii) nerve tissue engineering strategies are discussed and (iii) physiochemical properties of synthetic polymeric biomaterials systematically highlighted. Moreover, tailoring synthetic polymeric biomaterials for nerve tissue engineering is reviewed.


Assuntos
Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Tecido Nervoso/citologia , Tecido Nervoso/efeitos dos fármacos , Polímeros/química , Polímeros/farmacologia , Engenharia Tecidual/métodos , Animais , Materiais Biocompatíveis/síntese química , Humanos , Polímeros/síntese química
14.
Carbohydr Polym ; 223: 115118, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31426975

RESUMO

New biocompatible amphiphilic block copolymers were prepared using two natural compounds as starting materials, a polysaccharide (dextran) and a bile acid (deoxycholic acid). The copolymers were synthesized by dipolar 1,3-cycloaddition reaction between dextran with azide end groups and deoxycholic acid - oligo(ethylene glycol)s polyester with propargyl end groups. Different copolymer composition were obtained by variation of molecular weights of dextran (Mn 4.5, 8, 15 kDa) and polyester (Mn 2-6 kDa), as well as the length of oligo(ethylene glycol) (2-4 ethylenglycol units) used for polyester synthesis. These copolymers can for micelle like aggregates in aqueous medium with nanometric size (50-600 nm) and spherical form, as assessed by light scattering, atomic force microscopy and transmission electron microscopy. Encapsulation of the hydrophobic drug curcumin in micelles could increase 68,181 times its water solubility, and curcumin release from micelles was slow and with reduced burst effect.


Assuntos
Antineoplásicos/química , Materiais Biocompatíveis/síntese química , Curcumina/química , Ácido Desoxicólico/química , Dextranos/química , Polímeros/síntese química , Tensoativos/síntese química , Materiais Biocompatíveis/química , Cápsulas/química , Liberação Controlada de Fármacos , Interações Hidrofóbicas e Hidrofílicas , Micelas , Conformação Molecular , Tamanho da Partícula , Polímeros/química , Solubilidade , Propriedades de Superfície , Tensoativos/química
15.
Nanoscale ; 11(30): 14237-14241, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31317999

RESUMO

The construction of the hierarchical nanostructures of inorganic materials with high stability has attracted great attention for photothermal therapy. In this paper, we presented the preparation of urchin-like LaWO4Cl nanostructures assembled with nanoribbons via a facile solvothermal reaction. X-ray diffraction (XRD) analysis confirmed the formation of good crystalline urchin-like LaWO4Cl assemblies. Energy dispersive X-ray spectroscopy (EDX) and X-ray photoelectron spectroscopy (XPS) revealed the element composition of the prepared urchin-like nanostructures. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) investigations showed that the urchin-like LaWO4Cl assemblies were composed of single crystalline nanoribbons with diameters less than 10 nm. When excited with an 808 nm near-infrared (NIR) laser at the power density of 1.91 W cm-2 for 5 min, the temperature quickly increased to 52 °C. The in vitro cytotoxicity of urchin-like LaWO4Cl was tested with human cervical cancer cells (HeLa), revealing excellent biocompatibility. More importantly, the photothermal treatment with urchin-like LaWO4Cl displayed great therapeutic efficacy in vitro. Thus, urchin-like LaWO4Cl would be a new promising NIR light-driven photothermal agent, which can also pave a new way for the material design of PTT agents.


Assuntos
Materiais Biocompatíveis/química , Raios Infravermelhos , Nanoestruturas/química , Óxidos/química , Tungstênio/química , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Células HeLa , Humanos , Fototerapia
16.
J Mater Sci Mater Med ; 30(8): 88, 2019 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-31325082

RESUMO

Calcium phosphate (CaP)-containing materials, such as hydroxyapatite and brushite, are well studied bone grafting materials owing to their similar chemical compositions to the mineral phase of natural bone and kidney calculi. In recent studies, magnesium phosphate (MgP)-containing compounds, such as newberyite and struvite, have shown promise as alternatives to CaP. However, the different ways in degradation and release of Mg2+ and Ca2+ ions in vitro may affect the biocompatibility of CaP and MgP-containing compounds. In the present paper, newberyite, struvite, and brushite 3D porous structures were constructed by 3D-plotting combining with a two-step cementation process, using magnesium oxide (MgO) as a starting material. Briefly, 3D porous green bodies fabricated by 3D-plotting were soaked in (NH4)2HPO4 solution to form semi-manufactured 3D porous structures. These structures were then soaked in different phosphate solutions to translate the structures into newberyite, struvite, and brushite porous scaffolds. Powder X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive spectrometry (EDS) were used to characterize the phases, morphologies, and compositions of the 3D porous scaffolds. The porosity, compressive strength, in vitro degradation and cytotoxicity on MC3T3-E1 osteoblast cells were assessed as well. The results showed that extracts obtained from immersing scaffolds in alpha-modified essential media induced minimal cytotoxicity and the cells could be attached merely onto newberyite and brushite scaffolds. Newberyite and brushite scaffolds produced through our 3D-plotting and two-step cementation process showed the sustained in vitro degradation and excellent biocompatibility, which could be used as scaffolds for the bone tissue engineering.


Assuntos
Materiais Biocompatíveis/síntese química , Fosfatos de Cálcio/química , Compostos de Magnésio/química , Óxido de Magnésio/farmacologia , Microtecnologia/métodos , Fosfatos/química , Estruvita/química , Tecidos Suporte/química , Animais , Materiais Biocompatíveis/química , Cimentos para Ossos/síntese química , Cimentos para Ossos/química , Células Cultivadas , Precipitação Química/efeitos dos fármacos , Força Compressiva , Óxido de Magnésio/química , Teste de Materiais , Camundongos , Conformação Molecular , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Osteoblastos/fisiologia , Polimerização/efeitos dos fármacos , Porosidade , Pós/síntese química , Pós/química , Engenharia Tecidual/instrumentação , Engenharia Tecidual/métodos
17.
Molecules ; 24(14)2019 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-31330957

RESUMO

Massive blood loss is responsible for numerous causes of death. Hemorrhage may occur on the battlefield, at home or during surgery. Commercially available biomaterials may be insufficient to deal with excessive bleeding. Therefore novel, highly efficient hemostatic agents must be developed. The aim of the following research was to obtain a new type of biocompatible chitosan-based hemostatic agents with increased hemostatic properties. The biomaterials were obtained in a quick and efficient manner under microwave radiation using l-aspartic and l-glutamic acid as crosslinking agents with no use of acetic acid. Ready products were investigated over their chemical structure by FT-IR method which confirmed a crosslinking process through the formation of amide bonds. Their high porosity above 90% and low density (below 0.08 g/cm3) were confirmed. The aerogels were also studied over their water vapor permeability and antioxidant activity. Prepared biomaterials were biodegradable in the presence of human lysozyme. All of the samples had excellent hemostatic properties in contact with human blood due to the platelet activation confirmed by blood clotting tests. The SEM microphotographs showed the adherence of blood cells to the biomaterials' surface. Moreover, they were biocompatible with human dermal fibroblasts (HDFs). The biomaterials also had superior antibacterial properties against both Staphylococcus aureus and Escherichia coli. The obtained results showed that proposed chitosan-based hemostatic agents have great potential as a hemostatic product and may be applied under sterile, as well as contaminated conditions, by both medicals and individuals.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Quitosana/química , Hemostáticos/química , Hemostáticos/farmacologia , Antibacterianos/síntese química , Antioxidantes/síntese química , Antioxidantes/química , Antioxidantes/farmacologia , Bactérias/efeitos dos fármacos , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Coagulação Sanguínea/efeitos dos fármacos , Técnicas de Química Sintética , Hemostáticos/síntese química , Teste de Materiais , Testes de Sensibilidade Microbiana , Estrutura Molecular , Porosidade , Análise Espectral , Relação Estrutura-Atividade
18.
Biomater Sci ; 7(9): 3599-3608, 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31339146

RESUMO

Bio-inspired wet adhesives attract considerable attention in the biomedical field. However, achieving reversible and controllable wet adhesion still remains a challenging issue. In this study, we report a new thermo-responsive polysaccharide wet adhesive conjugate named Chitosan-Catechol-poly(N-isopropyl acrylamide) (Chitosan-Catechol-pNIPAM), where catechol, the wet adhesive moiety, and pNIPAM, the thermal responsive group, are chemically tethered to a chitosan backbone. The as-synthesized Chitosan-Catechol-pNIPAM presents a reversible sol-gel transition behavior when the temperature is cycled below and above the lower critical solution temperature (LCST, 35 °C), along with dynamic switching between lubrication and wet adhesion on various materials. Based on these excellent features, Chitosan-Catechol-pNIPAM can realize controllable attachment/detachment behavior over the skin through heating/cooling processes. Due to its good biocompatibility, the Chitosan-Catechol-pNIPAM coated syringe needles exhibit instant hemostasis after removing the needles from the punctured sites of mouse veins. Overall, the as-synthesized Chitosan-Catechol-pNIPAM is expected to be used as a new intelligent adhesive in various biomedical settings.


Assuntos
Resinas Acrílicas/química , Materiais Biocompatíveis/química , Catecóis/química , Quitosana/química , Hemostasia , Adesivos Teciduais/química , Animais , Materiais Biocompatíveis/síntese química , Masculino , Camundongos , Coelhos , Ratos , Ratos Wistar , Aderências Teciduais , Adesivos Teciduais/síntese química
19.
Biomater Sci ; 7(9): 3764-3778, 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31342016

RESUMO

Fluorinated polymers are strong candidates for development of new cardiovascular medical devices, due to their lower thrombogenicity as compared to other polymers used for cardiovascular implants. Few studies have reported the development of fluorinated polyesters and their potential in blood contact applications has never been examined. In this study, we developed a versatile method for preparing trifluoromethyl-functionalized poly(lactic acid) that can be potentially extended to prepare a new class of polyesters with various halogen or halocarbon substitutions. The resulting fluorinated polymer was hydrophobic relative to poly(lactic acid) and extracts from this polymer showed no in vitro cytotoxicity to NIH-3T3 mouse fibroblast cells. A preliminary consideration of the blood interactions of the CF3-functionalized polyester was evaluated by measuring the amount of the adsorbed albumin and fibrinogen from human blood plasma. The fluorinated polyester adsorbed and retained higher amounts of albumin and fibrinogen with a higher albumin/fibrinogen ratio as compared to poly(lactic acid), suggesting enhanced hemocompatibility. Plasma protein adsorption is the first event that occurs seconds after device implantation and controlling the adsorbed proteins will dictate the performance of medical implants.


Assuntos
Materiais Biocompatíveis/química , Hidrocarbonetos Fluorados/sangue , Hidrocarbonetos Fluorados/química , Poliésteres/química , Adsorção , Animais , Materiais Biocompatíveis/síntese química , Células Cultivadas , Fibrinogênio/química , Humanos , Interações Hidrofóbicas e Hidrofílicas , Camundongos , Estrutura Molecular , Células NIH 3T3 , Poliésteres/síntese química , Albumina Sérica Humana/química , Propriedades de Superfície
20.
Colloids Surf B Biointerfaces ; 182: 110353, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31336281

RESUMO

Great advantages bestowed by mesoporous silica nanoparticles (MSNs) including high surface area, tailorable pore diameter and surface chemistry, and large pore volume render them as efficient tools in biomedical applications. Herein, MSNs with different surface chemistries were synthesized and investigated in terms of biocompatibility and their impact on the morphology of bone marrow-derived mesenchymal stem cells both in 2D and 3D culture systems. Bare MSNs (BMSNs) were synthesized by template removing method using tetraethylorthosilicate (TEOS) as a precursor. The as-prepared BMSNs were then used to prepare amine-functionalized (AMSNs), carboxyl-functionalized (CMSNs) and polymeric amine-functionalized (PMSNs) samples, consecutively. These nanoparticles were characterized by scanning electron microscopy, zeta potential measurement, dynamic light scattering, BET (Brunauer, Emmett, Teller) analysis, and FTIR technique. In a 3D culture system, stem cells were encapsulated in alginate hydrogel in which MSNs of different functionalities were incorporated. The results showed good biocompatibility for both BMSNs and AMSNs in 2D and 3D culture systems. For these samples, the viability of about 80% was acquired after 2 weeks of 3D culture. When compared to the control, CMSNs caused higher cell proliferation in the 2D culture; while they showed cytotoxic effects in the 3D culture system. Interestingly, polymeric amine-functionalized silica nanoparticles (PMSNs) resulted in disrupted morphology and very low viability in the 2D cell culture and even less viability in 3D environment in comparison to BMSNs and AMSNs. This significant decrease in cell viability was attributed to the higher uptake values of highly positively charged PMSNs by cells as compared to other MSNs. This up-regulated uptake was evaluated by using an inductively coupled plasma optical emission spectroscopy instrument (ICP-OES). These results uncover different interactions between cell and nanoparticles with various surface chemistries. Building on these results, new windows are opened for employing biocompatible nanoparticles such as BMSNs and AMSNs, even at high concentrations, as potential cargos for carrying required growth and/or differentiation factors for tissue engineering applications.


Assuntos
Materiais Biocompatíveis/síntese química , Células-Tronco Mesenquimais/efeitos dos fármacos , Nanopartículas/química , Dióxido de Silício/química , Alginatos/química , Materiais Biocompatíveis/farmacologia , Técnicas de Cultura de Células , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Humanos , Hidrogéis , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/fisiologia , Nanopartículas/ultraestrutura , Porosidade , Silanos/química , Dióxido de Silício/farmacologia , Eletricidade Estática , Relação Estrutura-Atividade , Propriedades de Superfície , Engenharia Tecidual/métodos
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