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1.
Nat Commun ; 11(1): 4848, 2020 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-32973166

RESUMO

Polydopamine (PDA) is a simple and versatile conformal coating material that has been proposed for a variety of uses; however in practice its performance is often hindered by poor mechanical properties and high roughness. Here, we show that blue-diode laser annealing dramatically improves mechanical performance and reduces roughness of PDA coatings. Laser-annealed PDA (LAPDA) was shown to be >100-fold more scratch resistant than pristine PDA and even better than hard inorganic substrates, which we attribute to partial graphitization and covalent coupling between PDA subunits during annealing. Moreover, laser annealing provides these benefits while preserving other attractive properties of PDA, as demonstrated by the superior biofouling resistance of antifouling polymer-grafted LAPDA compared to PDA modified with the same polymer. Our work suggests that laser annealing may allow the use of PDA in mechanically demanding applications previously considered inaccessible, without sacrificing the functional versatility that is so characteristic of PDA.


Assuntos
Indóis/química , Indóis/efeitos da radiação , Lasers , Polímeros/química , Polímeros/efeitos da radiação , Incrustação Biológica , Materiais Revestidos Biocompatíveis/química , Teste de Materiais , Propriedades de Superfície
2.
PLoS One ; 15(7): e0235283, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32614918

RESUMO

Recurrent caries, the development of carious lesions at the interface between the restorative material and the tooth structure, is highly prevalent and represents the primary cause for failure of dental restorations. Correspondingly, we exploited the self-assembly and strong antibiofilm activity of amphipathic antimicrobial peptides (AAMPs) to form novel coatings on dentin that aimed to prevent recurrent caries at susceptible cavosurface margins. AAMPs are alternative to traditional antimicrobial agents and antibiotics with the ability to target the complex and heterogeneous organization of microbial communities. Unlike approaches that have focused on using these AAMPs in aqueous solutions for a transient activity, here we assess the effects on microcosm biofilms of a long-acting AAMPs-based antibiofilm coating to protect the tooth-composite interface. Genomewise, we studied the impact of AAMPs coatings on the dental plaque microbial community. We found that non-native all D-amino acids AAMPs coatings induced a marked shift in the plaque community and selectively targeted three primary acidogenic colonizers, including the most common taxa around Class II composite restorations. Accordingly, we investigated the translational potential of our antibiofilm dentin using multiphoton pulsed near infra-red laser for deep bioimaging to assess the impact of AAMPs-coated dentin on plaque biofilms along dentin-composite interfaces. Multiphoton enabled us to record the antibiofilm potency of AAMPs-coated dentin on plaque biofilms throughout exaggeratedly failed interfaces. In conclusion, AAMPs-coatings on dentin showed selective and long-acting antibiofilm activity against three dominant acidogenic colonizers and potential to resist recurrent caries to promote and sustain the interfacial integrity of adhesive-based interfaces.


Assuntos
Anti-Infecciosos/administração & dosagem , Peptídeos Catiônicos Antimicrobianos/administração & dosagem , Biofilmes/efeitos dos fármacos , Placa Dentária/tratamento farmacológico , Anti-Infecciosos/farmacologia , Peptídeos Catiônicos Antimicrobianos/farmacologia , Biofilmes/crescimento & desenvolvimento , Materiais Revestidos Biocompatíveis/química , Dentina/química , Dentina/microbiologia , Durapatita/química , Humanos , Proteínas Imobilizadas/administração & dosagem , Proteínas Imobilizadas/farmacologia , Microbiota/efeitos dos fármacos
3.
Proc Natl Acad Sci U S A ; 117(28): 16127-16137, 2020 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-32601214

RESUMO

Thrombogenic reaction, aggressive smooth muscle cell (SMC) proliferation, and sluggish endothelial cell (EC) migration onto bioinert metal vascular stents make poststenting reendothelialization a dilemma. Here, we report an easy to perform, biomimetic surface engineering strategy for multiple functionalization of metal vascular stents. We first design and graft a clickable mussel-inspired peptide onto the stent surface via mussel-inspired adhesion. Then, two vasoactive moieties [i.e., the nitric-oxide (NO)-generating organoselenium (SeCA) and the endothelial progenitor cell (EPC)-targeting peptide (TPS)] are clicked onto the grafted surfaces via bioorthogonal conjugation. We optimize the blood and vascular cell compatibilities of the grafted surfaces through changing the SeCA/TPS feeding ratios. At the optimal ratio of 2:2, the surface-engineered stents demonstrate superior inhibition of thrombosis and SMC migration and proliferation, promotion of EPC recruitment, adhesion, and proliferation, as well as prevention of in-stent restenosis (ISR). Overall, our biomimetic surface engineering strategy represents a promising solution to address clinical complications of cardiovascular stents and other blood-contacting metal materials.


Assuntos
Adesivos/química , Materiais Revestidos Biocompatíveis/química , Peptídeos/química , Stents , Adesivos/síntese química , Animais , Materiais Biomiméticos/síntese química , Materiais Biomiméticos/química , Adesão Celular , Movimento Celular , Proliferação de Células , Células Cultivadas , Química Click , Células Progenitoras Endoteliais/citologia , Endotélio Vascular/citologia , Endotélio Vascular/fisiologia , Humanos , Miócitos de Músculo Liso/citologia , Óxido Nítrico/química , Compostos Organosselênicos/química , Peptídeos/síntese química , Proteínas/química , Coelhos , Stents/efeitos adversos , Trombose/etiologia , Trombose/prevenção & controle
4.
Int J Nanomedicine ; 15: 2605-2615, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32368043

RESUMO

Objective: This paper introduces a simple one-step and ultra-fast method for synthesis of highly photothermally active polypyrrole-coated gold nanoparticles. The synthesis process is so simple that the reaction is very fast without the need for any additives or complicated steps. Methodology: Polypyrrole-coated gold nanoparticles (AuPpy NPs) were synthesized by reacting chloroauric acid (HAuCl4) with pyrrole (monomer) in aqueous medium at room temperature. These nanoparticles were characterized by UV-visible-NIR spectrometry, transmission electron microscopy (TEM), AC conductivity, zeta sizer and were evaluated for dark cytotoxicity and photocytotoxicity using human hepatocellular carcinoma (HepG2) cell line as a model for cancer cells. Results: The synthesized AuPpy NPs showed a peak characteristic for gold nanoparticles (530-600 nm, molar ratio dependent) and a wide absorption band along the visible-NIR region with intensity about triple or even quadruple that of polypyrrole synthesized by the conventional FeCl3 method at the same concentration and under the same conditions. TEM imaging showed that the synthesized AuPpy NPs were composed of spherical or semi-spherical gold core(s) of about 4-10 nm coated with distinct layer(s) of polypyrrole seen either loosely or in clusters. Mean sizes of the synthesized nanoparticles range between ~25 and 220 nm (molar ratio dependent). Zeta potentials of the AuPpy NPs preparations indicate their good colloidal stability. AC conductivity values of AuPpy NPs highly surpass that of Ppy prepared by the conventional FeCl3 method. AuPpy NPs were non-toxic even at high concentrations (up to 1000 µM pyrrole monomer equivalent) under dark conditions. Unlikely, light activated the photothermal activity of AuPpy NPs in a dose-dependent manner. Conclusion: This method simply and successfully synthesized AuPpy NPs nanoparticles that represent a safe alternative photothermally active multifunctional tool instead of highly toxic and non-biodegradable gold nanorods.


Assuntos
Materiais Revestidos Biocompatíveis/química , Ouro/química , Luz , Nanopartículas Metálicas/química , Polímeros/química , Pirróis/química , Temperatura , Morte Celular , Cloretos/química , Condutividade Elétrica , Compostos de Ouro/química , Células Hep G2 , Humanos , Nanopartículas Metálicas/ultraestrutura , Tamanho da Partícula , Polímeros/síntese química , Pirróis/síntese química , Espectrofotometria Ultravioleta , Eletricidade Estática
5.
PLoS One ; 15(5): e0232851, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32392238

RESUMO

Here we present the synthesis and characterization of two new conducting materials having a high electro-chemo-mechanical activity for possible applications as artificial muscles or soft smart actuators in biomimetic structures. Glucose-gelatin nanofiber scaffolds (CFS) were coated with polypyrrole (PPy) first by chemical polymerization followed by electrochemical polymerization doped with dodecylbenzensulfonate (DBS-) forming CFS-PPy/DBS films, or with trifluoromethanesulfonate (CF3SO3-, TF) giving CFS-PPy/TF films. The composition, electronic and ionic conductivity of the materials were determined using different techniques. The electro-chemo-mechanical characterization of the films was carried out by cyclic voltammetry and square wave potential steps in bis(trifluoromethane)sulfonimide lithium solutions of propylene carbonate (LiTFSI-PC). Linear actuation of the CFS-PPy/DBS material exhibited 20% of strain variation with a stress of 0.14 MPa, rather similar to skeletal muscles. After 1000 cycles, the creeping effect was as low as 0,2% having a good long-term stability showing a strain variation per cycle of -1.8% (after 1000 cycles). Those material properties are excellent for future technological applications as artificial muscles, batteries, smart membranes, and so on.


Assuntos
Órgãos Artificiais , Materiais Biomiméticos , Materiais Revestidos Biocompatíveis/química , Nanofibras , Polímeros/química , Pirróis/química , Tecidos Suporte , Benzenossulfonatos/química , Condutividade Elétrica , Eletroquímica , Gelatina/química , Glucose/química , Mesilatos/química , Microscopia Eletrônica de Varredura , Músculos , Nanofibras/química , Nanofibras/ultraestrutura , Polimerização , Potenciometria , Espectrometria por Raios X , Espectroscopia de Infravermelho com Transformada de Fourier , Estresse Mecânico , Propriedades de Superfície , Tecidos Suporte/química
6.
Int J Nanomedicine ; 15: 1267-1281, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32161457

RESUMO

Background: Joint arthroplasty has improved the quality of life of patients worldwide, but infections of the prosthesis are frequent and cause significant morbidity. Antimicrobial coatings for implants promise to prevent these infections. Methods: We have synthesized nanocapsules of titanium dioxide in amorphous or anatase form containing silver as antibacterial agent and tested their impact on bacterial growth. Furthermore, we explored the possible effect of the nanocapsules on the immune system. First, we studied their uptake into macrophages using a combination of electron microscopy and energy-dispersive spectroscopy. Second, we exposed immune cells to the nanocapsules and checked their activation state by flow cytometry and enzyme-linked immunosorbent assay. Results: Silver-containing titanium dioxide nanocapsules show strong antimicrobial activity against both E. coli and S. aureus and even against a multidrug-resistant strain of S. aureus. We could demonstrate the presence of the nanocapsules in macrophages, but, importantly, the nanocapsules did not affect cell viability and did not activate proinflammatory responses at doses up to 20 µg/mL. Conclusion: Our bactericidal silver-containing titanium dioxide nanocapsules fulfill important prerequisites for biomedical use and represent a promising material for the coating of artificial implants.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Nanocápsulas/química , Animais , Materiais Revestidos Biocompatíveis/química , Escherichia coli/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Testes de Sensibilidade Microbiana , Nanocápsulas/uso terapêutico , Prata/química , Prata/farmacocinética , Staphylococcus aureus/efeitos dos fármacos , Titânio/química
7.
Int J Nanomedicine ; 15: 1797-1807, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32214812

RESUMO

Purpose: Enhancing osteointegration of implants in osteoporosis patients is a necessity since implantations frequently fail in these patients. The aim of this work is to study how simvastatin-strontium-hydroxyapatite coated implants perform in rabbits with osteoporosis. Materials and Methods: Crystalline HA and Sr-HA oxide film were prepared through micro-arc oxidation. Surface characterization including morphology, roughness, element composition, phase composition, hydrophilicity were then evaluated. Simvastatin loaded on porous films through immersion, and the effects of coatings on osteointegration in osteoporotic rabbits were investigated. All samples were obtained after 4, 8 and 12 weeks of healing. Some of them were subjected to biomechanical tests and others were subjected to histological and histomorphometric analysis. Results: Coatings exhibited a microporous network structure with appropriate roughness and high hydrophilicity. Compared to control HA and machined surface implants, simvastatin-Sr-HA coated implants exhibited marked improvements in osteointegration, which is characterized by a quicker mineralization deposition rate, good bone formation mode (large amount of contact osteogenesis and a small amount of distance osteogenesis) and increased bone-to-implant contact and pull-out strength. Conclusion: These biological parameters demonstrate the excellent osteoconductivity of simvastatin-Sr-HA coatings in the osteoporotic state. Overall, this suggests that simvastatin-Sr-HA coatings would be applicable in poor-quality bones of patients experiencing osteoporosis.


Assuntos
Osseointegração/efeitos dos fármacos , Osteoporose/patologia , Próteses e Implantes , Sinvastatina/farmacologia , Animais , Interface Osso-Implante , Materiais Revestidos Biocompatíveis/química , Feminino , Hidroxiapatitas/química , Osteogênese/efeitos dos fármacos , Oxirredução , Coelhos , Sinvastatina/química , Estrôncio/química , Tíbia/fisiopatologia
8.
Nat Commun ; 11(1): 862, 2020 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-32054841

RESUMO

Complex hierarchical structure governs emergent properties in biopolymeric materials; yet, the material processing involved remains poorly understood. Here, we investigated the multi-scale structure and composition of the mussel byssus cuticle before, during and after formation to gain insight into the processing of this hard, yet extensible metal cross-linked protein composite. Our findings reveal that the granular substructure crucial to the cuticle's function as a wear-resistant coating of an extensible polymer fiber is pre-organized in condensed liquid phase secretory vesicles. These are phase-separated into DOPA-rich proto-granules enveloped in a sulfur-rich proto-matrix which fuses during secretion, forming the sub-structure of the cuticle. Metal ions are added subsequently in a site-specific way, with iron contained in the sulfur-rich matrix and vanadium coordinated by DOPA-catechol in the granule. We posit that this hierarchical structure self-organizes via phase separation of specific amphiphilic proteins within secretory vesicles, resulting in a meso-scale structuring that governs cuticle function.


Assuntos
Materiais Revestidos Biocompatíveis/química , Metaloproteínas/química , Mytilus edulis/química , Estruturas Animais/anatomia & histologia , Estruturas Animais/química , Estruturas Animais/ultraestrutura , Animais , Di-Hidroxifenilalanina/química , Imageamento Tridimensional , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Mytilus edulis/anatomia & histologia , Mytilus edulis/ultraestrutura , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Vesículas Secretórias/química , Vesículas Secretórias/ultraestrutura
9.
Colloids Surf B Biointerfaces ; 188: 110783, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32004907

RESUMO

The failure of dental implants is usually caused by bacteria infection, poor bioactivity and biocompatibility. It is a common phenomenon clinically. Statherin, a salivary protein, plays a crucial role of mediator between materials and cells/bacteria. However, the conformation of statherin might be changed by the implants in vivo. In this study, we investigated the effects of statherin on the bioactivities, antibacterial abilities and biocompatibilities of the titanium metals and the reaction mechanism. We found that the conformation of statherin was mainly influenced by surface composition, surface structure, surface roughness, surface hydrophilia and Ti-OH groups of materials. Statherin could decrease the cell biocompatibility of the titanium metals including pure titanium (PT), anodic oxidation (AO), sandblasting and etching (SLA) and plasma spraying hydroxyapatite (HA) coating in HGF cell experiments, regulate the bio-mineralization ability of HA coating in SBF, and enhance the antibacterial properties of PT and HA coating. This study revealed that surface properties of materials could change the conformation of statherin, which influenced the bioactivities, antibacterial properties and biocompatibilities of the materials in return.


Assuntos
Antibacterianos/metabolismo , Materiais Revestidos Biocompatíveis/metabolismo , Proteínas e Peptídeos Salivares/metabolismo , Titânio/metabolismo , Adsorção , Antibacterianos/química , Antibacterianos/farmacologia , Linhagem Celular , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Implantes Dentários , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Humanos , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Conformação Proteica , Proteínas e Peptídeos Salivares/química , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento , Propriedades de Superfície , Titânio/química , Titânio/farmacologia
10.
PLoS One ; 15(1): e0228247, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31999748

RESUMO

Magnesium-based biomaterials are attracting increasingly more attention for orthopedic applications based on their appropriate mechanical properties, biodegradability, and favorable biocompatibility. However, the high corrosion rate of these materials remains to be addressed. In this study, porous ß-Ca3(PO4)2/Mg-Zn (ß-TCP/Mg-Zn) composites were fabricated via a powder metallurgy method. The ß-TCP/Mg-Zn composites with 6% porosity exhibited optimal mechanical properties, and thus, they were selected for surface modification. A novel dopamine/gelatin/recombinant human bone morphogenetic protein-2 (rhBMP-2) coating with demonstrated stability was prepared to further improve the corrosion resistance of the composite and enhance early osteoinductivity. The homogeneously coated ß-TCP/Mg-Zn composite showed significantly improved corrosion resistance according to electrochemical and immersion tests. In addition, extracts from the dopamine/gelatin/rhBMP-2-coated ß-TCP/Mg-Zn composite not only facilitated cell proliferation but also significantly enhanced the osteogenic differentiation of Sprague-Dawley rat bone marrow-derived mesenchymal stem cells in vitro. Furthermore, in vivo experiments were performed to evaluate the biodegradation, histocompatibility, and osteoinductive potential of the coated composite. No obvious pathological changes in the vital visceral organs were observed after implantation, and radiography and hematoxylin-eosin staining showed strong promotion of new bone formation, matched composite degradation and bone regeneration rates, and complete absorption of the released hydrogen gas. Collectively, these results indicate that the dopamine/gelatin/rhBMP-2-coated ß-TCP/Mg-Zn composite offers improved corrosion resistance, favorable biocompatibility, and enhanced osteoinductive potential for use in the fabrication of orthopedic implants.


Assuntos
Osso e Ossos , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Teste de Materiais , Próteses e Implantes , Animais , Proteína Morfogenética Óssea 2 , Fosfatos de Cálcio , Dopamina , Feminino , Gelatina , Magnésio , Masculino , Células-Tronco Mesenquimais , Coelhos , Ratos , Zinco
11.
Mater Sci Eng C Mater Biol Appl ; 108: 110430, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31923959

RESUMO

Functionalization of porous metals with antibacterial coatings is hotly pursued in recent decade. Here we fabricated a highly porous stainless steel component by selective laser melting and then coated with silver incorporated zeolite by in situ hydrothermal crystallization method. The morphology of their surface was investigated by scanning electron microscopy. The inhibition of Escherichia coli and Staphylococcus aureus were identified by bacterial viability studies after 24 h of incubation. More importantly, the obtained coatings show better osteointegration by spreading bone marrow stromal cells (BMSCs) after cultured with different scaffold extract solutions for 1, 3, and 5 days. These results suggest that silver incorporated zeolite coatings on 3D printed porous stainless steels exhibit better antibacterial activity and biocompatibility, showing potential application in the field of medical implant materials.


Assuntos
Antibacterianos , Materiais Revestidos Biocompatíveis , Escherichia coli/crescimento & desenvolvimento , Impressão Tridimensional , Prata , Aço Inoxidável , Staphylococcus aureus/crescimento & desenvolvimento , Zeolitas , Antibacterianos/química , Antibacterianos/farmacologia , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Porosidade , Prata/química , Prata/farmacologia , Aço Inoxidável/química , Aço Inoxidável/farmacologia , Zeolitas/química , Zeolitas/farmacologia
12.
Carbohydr Polym ; 232: 115817, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31952614

RESUMO

Chitosan (Chi) and anionic surfactant derived from lysine (77KS) were used to prepare a novel bioactive coating and as a drug delivery system for amoxicillin (AMOX) on a model polydimethylsiloxane (PDMS) surface. The bioactive coating was formulated as polyelectrolyte-surfactant complex (PESC). Aggregation behaviour between the cationic Chi and oppositely charged 77KS in bulk was analysed using turbidity and ζ-potential measurement. Furthermore, the adsorption and stability of the formulations were evaluated using quartz crystal microbalance with dissipation (QCM-D). The effect of the ionic strength and of the ultraviolet/ozone (UVO) activation of the PDMS films on the adsorption behaviour of the PESC complex was also examined. QCM-D monitoring showed stable adsorption of bare and AMOX-loaded complex on non-activated PDMS films, while the coating on UVO-activated PDMS samples desorbed after the rinsing step. Finally, X-ray photoelectron spectroscopy and time-of-flight secondary ion mass spectrometry confirmed successful and homogenously distributed compounds.


Assuntos
Quitosana/química , Materiais Revestidos Biocompatíveis/química , Lisina/química , Silicones/química , Tensoativos/química , Amoxicilina/química , Antibacterianos/química , Humanos , Estrutura Molecular , Propriedades de Superfície
14.
Molecules ; 25(1)2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-31935900

RESUMO

Currently, significant attention is attracted to the problem of the development of the specific architecture and composition of the surface layer in order to control the biocompatibility of implants made of titanium and its alloys. The titanium surface properties can be tuned both by creating an inorganic sublayer with the desired morphology and by organic top coating contributing to bioactivity. In this work, we developed a composite biologically active coatings based on hybrid molecules obtained by chemical cross-linking of amino acid bisphosphonates with a linear tripeptide RGD, in combination with inorganic porous sublayer created on titanium by plasma electrolytic oxidation (PEO). After the addition of organic molecules, the PEO coated surface gets nobler, but corrosion currents increase. In vitro studies on proliferation and viability of fibroblasts, mesenchymal stem cells and osteoblast-like cells showed the significant dependence of the molecule bioactivity on the structure of bisphosphonate anchor and the linker. Several RGD-modified bisphosphonates of ß-alanine, γ-aminobutyric and ε-aminocaproic acids with BMPS or SMCC linkers can be recommended as promising candidates for further in vivo research.


Assuntos
Materiais Revestidos Biocompatíveis , Oligopeptídeos , Ácidos Fosforosos , Próteses e Implantes , Titânio , Linhagem Celular , Materiais Revestidos Biocompatíveis/química , Eletroquímica , Humanos , Teste de Materiais , Células-Tronco Mesenquimais/metabolismo , Oligopeptídeos/química , Osteoblastos/metabolismo , Ácidos Fosforosos/química , Análise Espectral , Propriedades de Superfície , Titânio/química
15.
Carbohydr Polym ; 230: 115466, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31887965

RESUMO

Seven natural polymers namely, chitosan (CHI), dextran (Dex), carboxymethyl cellulose (CMC), sodium alginate (ALG), pectin (PEC), hydroxylethyl cellulose (HEC), and Gum Arabic (GA) were screened for anticorrosion property towards AZ31 Mg alloy in 3.5 wt.% NaCl solution. CHI, Dex, CMC, PEC, and GA accelerated the corrosion while ALG and HEC moderately inhibited the corrosion of the alloy. HEC and ALG (1 g/L) protected the alloy by 64.13 % and 58.27 %, respectively. Two inhibitor cocktails consisting of either HEC or ALG, KI, and Date palm seed oil have been formulated. HEC- and ALG-formulations inhibited the alloy corrosion by 80.56 % and 77.43 %, respectively from EIS technique. Surface observation studies using SECM, AFM, SEM, and EDX agreed with other experimental results revealing effective corrosion inhibition by the formulations. X-ray photoelectron spectroscopy, FTIR, and UV-vis results disclose that Mg(OH)2 co-existed with adsorbed inhibitor complexes.


Assuntos
Ligas/química , Materiais Revestidos Biocompatíveis/química , Corrosão , Polímeros/química , Adsorção/efeitos dos fármacos , Alginatos/química , Carboximetilcelulose Sódica/química , Quitosana/química , Goma Arábica/química , Magnésio/química , Teste de Materiais , Propriedades de Superfície
16.
Mater Sci Eng C Mater Biol Appl ; 108: 110192, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31923966

RESUMO

This study provided an eco-friendly manufacturing method for Ti implants by combining machining and surface treatment processes. Ti was machined by electrical discharge machining (EDM) in a water-based dielectric in order to reduce environmental impact and improve operational health. The feasibility of this eco-friendly EDM was evaluated by tested the bioactivity and cytocompatibility of the EDM-treated Ti and the commercially micro-arc oxidation (MAO)-treated Ti was used as a control group. Pulsed MAO and EDM treatments were applied on Ti in an aqueous solution containing hydroxyapatite (HA) with the same concentration (30 g/L) under the same voltage and treatment period. The two surface modification processes were compared from the aspects of surface composition, coating structure, and coating adhesion. Furthermore, in vitro bioactivity and cellular biocompatibility of the MAO- and EDM-treated Ti films were tested. Both treatments produced Ti oxide containing Ca and P on Ti, and the EDM-formed film possessed more Ca, with its Ca/P value closer to HA, as compared to the MAO-formed film. The MAO-formed films had micropores and nanopores in the middle region and film/substrate interface, respectively. Pores only existed on the surface of the EDM-formed films. The MAO-formed films were fractured, but the EDM-formed films maintained their original structure under tensile stress, tested according to the ASTM C633 standard. The bioactivity of the EDM-treated surface was higher than that of the MAO-treated and untreated Ti surface. After 24 h cell incubation, the EDM-treated surface exhibited a significantly higher number of cells than untreated Ti and the MAO-treated surface.


Assuntos
Materiais Revestidos Biocompatíveis , Técnicas Eletroquímicas , Teste de Materiais , Osteoblastos/metabolismo , Titânio , Linhagem Celular , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Técnicas Eletroquímicas/instrumentação , Técnicas Eletroquímicas/métodos , Estudos de Viabilidade , Humanos , Osteoblastos/citologia , Oxirredução , Propriedades de Superfície , Titânio/química , Titânio/farmacologia
17.
Mater Sci Eng C Mater Biol Appl ; 108: 110345, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31924041

RESUMO

Carbon Nanotubes (CNTs) are known for effective adhesion, growth, and differentiation of bone, muscle, and cardiac cells. CNTs can provide excellent mechanical and electrical properties for cell scaffolding; however, loose CNTs can cause in-vivo toxicity. To suppress this risk, our team has developed biomimetic scaffolds with multiscale hierarchy where carpet-like CNT arrays are covalently bonded to larger biocompatible substrates. In this study, we investigated the interaction between glioblastoma multiforme (GBM) cells (U87MG) and our unique hierarchical CNT-coated scaffolds upon brain tumor cell proliferation. U87MG cells grown on un-modified carbon scaffolds grew in a bi-phasic fashion. Initially, the scaffolds prevented GBM cell growth; however, prolonged growth on such scaffolds significantly increased GBM cell proliferation. We further defined the importance of the hydrophobicity/hydrophilicity of the CNT-coated scaffolds in this cellular response by utilizing sodium-hypochlorite based bleach treatment prior to cellular exposure. This surface modification increased the hydrophilicity of the CNT-coated scaffolds and ameliorated the biphasic response of U87MG cells allowing for a normal growth curve. Findings highlight the importance of surface modification and wettability of the CNT-coated scaffolds for cell growth applications. The focus for this study was to determine whether scaffold surface features could modulate tumor-scaffold interactions, and thus to improve our understanding of and optimize successful development of future scaffold-based chemotherapy applications. Overall, it appears that the wettability of carbon scaffolds coated with CNTs is an important regulator of U87MG cellular growth. These findings will be important to consider when developing a potential chemotherapy-attached implant to be used post-surgical resection for GBM patient treatment.


Assuntos
Proliferação de Células/efeitos dos fármacos , Materiais Revestidos Biocompatíveis , Glioblastoma , Nanotubos de Carbono/química , Tecidos Suporte/química , Linhagem Celular Tumoral , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Glioblastoma/metabolismo , Glioblastoma/patologia , Glioblastoma/terapia , Humanos
18.
Nanoscale ; 12(3): 1759-1778, 2020 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-31895375

RESUMO

Ultrasmall superparamagnetic iron oxide nanoparticles with a size <5 nm are emerging nanomaterials for their excellent biocompatibility, chemical stability, and tunable surface modifications. The applications explored include dual-modal or multi-modal imaging, drug delivery, theranostics and, more recently, magnetic resonance angiography. Good biocompatibility and biosafety are regarded as the preliminary requirements for their biomedical applications and further exploration in this field is still required. We previously synthesized and characterized ultrafine (average core size of 3 nm) silica-coated superparamagnetic iron oxide fluorescent nanoparticles, named sub-5 SIO-Fl, uniform in size, shape, chemical properties and composition. The cellular uptake and in vitro biocompatibility of the as-synthesized nanoparticles were demonstrated in a human colon cancer cellular model. Here, we investigated the biocompatibility of sub-5 SIO-Fl nanoparticles in human Amniotic Mesenchymal Stromal/Stem Cells (hAMSCs). Kinetic analysis of cellular uptake showed a quick nanoparticle internalization in the first hour, increasing over time and after long exposure (48 h), the uptake rate gradually slowed down. We demonstrated that after internalization, sub-5 SIO-Fl nanoparticles neither affect hAMSC growth, viability, morphology, cytoskeletal organization, cell cycle progression, immunophenotype, and the expression of pro-angiogenic and immunoregulatory paracrine factors nor the osteogenic and myogenic differentiation markers. Furthermore, sub-5 SIO-Fl nanoparticles were intravenously injected into mice to investigate the in vivo biodistribution and toxicity profile for a time period of 7 weeks. Our findings showed an immediate transient accumulation of nanoparticles in the kidney, followed by the liver and lungs, where iron contents increased over a 7-week period. Histopathology, hematology, serum pro-inflammatory response, body weight and mortality studies demonstrated a short- and long-term biocompatibility and biosafety profile with no apparent acute and chronic toxicity caused by these nanoparticles in mice. Overall, these results suggest the feasibility of using sub-5 SIO-Fl nanoparticles as a promising agent for stem cell magnetic targeting as well as for diagnostic and therapeutic applications in oncology.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Materiais Revestidos Biocompatíveis , Nanopartículas de Magnetita/química , Teste de Materiais , Células-Tronco Mesenquimais/metabolismo , Dióxido de Silício , Animais , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Feminino , Humanos , Células-Tronco Mesenquimais/citologia , Camundongos , Desenvolvimento Muscular/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Dióxido de Silício/química , Dióxido de Silício/farmacologia
19.
Adv Exp Med Biol ; 1251: 1-17, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31768968

RESUMO

Titanium implants are considered the gold standard of treatment for dental and orthopedic applications. Biocompatibility, low elasticity, and corrosion resistance are some of the key properties of these metallic implants. Nonetheless, a long-term clinical failure of implants may occur due to inadequate osseointegration. Poor osseointegration induces mobility, inflammation, increased bone resorption, and osteolysis; hence, it may result in painful revision surgeries. Topographical modifications, improvement in hydrophilicity, and the development of controlled-release drug-loading systems have shown to improve cellular adhesion, proliferation, and differentiation. Surface modifications, along with drug coating, undoubtedly demonstrate better osseointegration, especially in challenged degenerative conditions, such as osteoporosis, osteoarthritis, and osteogenesis imperfecta. Anabolic bone-acting drugs, such as parathyroid hormone peptides, simvastatin, prostaglandin-EP4-receptor antagonist, vitamin D, strontium ranelate, and anti-catabolic bone-acting drugs, such as calcitonin, bisphosphonates, and selective estrogen receptor modulators, expedite the process of osseointegration. In addition, various proteins, peptides, and growth factors may accessorize the idea of localized therapy. Loading these substances on modified titanium surfaces is achieved commonly by mechanisms such as direct coating, adsorption, and incorporating in biodegradable polymers. The primary approach toward the optimum drug loading is a critical trade-off between factors preventing release of a drug immediately and those allowing slow and sustained release. Recent advances broaden the understanding of the efficacy of adsorption, hydrogel coating, and electrospinning layer-by-layer coating facilitated by differential charge on metallic surface. This review discusses the existing approaches and challenges for the development of stable and sustained drug delivery systems on titanium implants, which would promote faster and superior osseointegration.


Assuntos
Osso e Ossos/citologia , Osso e Ossos/metabolismo , Materiais Revestidos Biocompatíveis/química , Sistemas de Liberação de Medicamentos , Osseointegração , Próteses e Implantes , Titânio , Animais , Adesão Celular , Implantes Dentários , Humanos , Propriedades de Superfície
20.
Biomater Sci ; 8(1): 391-404, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31728464

RESUMO

Prevention of bacterial infection and promotion of osseointegration are two important issues for titanium (Ti) implants in medical research. In addition, after a biofilm is formed on the surface of implants, the immune system and antibiotic therapy may fail. In this work, bio-functionalized titanium dioxide (TiO2)/molybdenum disulfide (MoS2)/polydopamine (PDA)/arginine-glycine-aspartic acid (RGD) nanorod arrays (NAs) are prepared on Ti implants to not only kill bacteria noninvasively upon co-irradiation of 660 nm visible light (VL) and 808 nm near infrared (NIR) light, but also promote the osteogenic activity simultaneously. Dual light irradiation triggers the TiO2/MoS2 NA to generate hyperthermia and reactive oxygen species (ROS) in 10 min. The synergistic effects of the generated hyperthermia and ROS increase the bacterial membrane permeability and bacteria are killed rapidly and efficiently in vitro and in vivo. The biofilm is also eradicated and RGD on the nanorods improves cell adhesion, proliferation, and osteogenic differentiation. The strategy described here for the design of bio-functionalized coatings on Ti implants has great clinical potential in orthopedics, dentistry, and other medical fields.


Assuntos
Antibacterianos/química , Materiais Revestidos Biocompatíveis/química , Luz , Nanotubos/química , Animais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Adesão Celular/efeitos dos fármacos , Linhagem Celular , Materiais Revestidos Biocompatíveis/farmacologia , Materiais Revestidos Biocompatíveis/uso terapêutico , Dissulfetos/química , Glutationa/química , Hipertermia Induzida , Indóis/química , Fígado/efeitos dos fármacos , Fígado/patologia , Camundongos , Molibdênio/química , Oligopeptídeos/química , Osteogênese/efeitos dos fármacos , Polímeros/química , Espécies Reativas de Oxigênio/metabolismo , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/patologia , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/patogenicidade , Titânio/química
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