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1.
Materials (Basel) ; 17(12)2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38930181

RESUMO

Three-dimensional printing (3DP) has emerged as a promising method for creating intricate scaffold designs. This study assessed three 3DP scaffold designs fabricated using biodegradable poly(lactic) acid (PLA) through fused deposition modelling (FDM): mesh, two channels (2C), and four channels (4C). To address the limitations of PLA, such as hydrophobic properties and poor cell attachment, a post-fabrication modification technique employing Polyelectrolyte Multilayers (PEMs) coating was implemented. The scaffolds underwent aminolysis followed by coating with SiCHA nanopowders dispersed in hyaluronic acid and collagen type I, and finally crosslinked the outermost coated layers with EDC/NHS solution to complete the hybrid scaffold production. The study employed rotating wall vessels (RWVs) to investigate how simulating microgravity affects cell proliferation and differentiation. Human mesenchymal stem cells (hMSCs) cultured on these scaffolds using proliferation medium (PM) and osteogenic media (OM), subjected to static (TCP) and dynamic (RWVs) conditions for 21 days, revealed superior performance of 4C hybrid scaffolds, particularly in OM. Compared to commercial hydroxyapatite scaffolds, these hybrid scaffolds demonstrated enhanced cell activity and survival. The pre-vascularisation concept on 4C hybrid scaffolds showed the proliferation of both HUVECs and hMSCs throughout the scaffolds, with a positive expression of osteogenic and angiogenic markers at the early stages.

2.
J Mech Behav Biomed Mater ; 128: 105122, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35168129

RESUMO

Dense iron-doped akermanite ceramics with 0.3, 0.6 and 0.9 mol% of Fe3+ were synthesized via high-speed planetary ball milling and subsequently subjected to sintering at 1200 and 1250 °C. The aim of the current work was to investigate the effect of trivalent iron (Fe3+) in tuning the physicomechanical and in vitro biological properties of akermanite. The incorporation of Fe3+ into akermanite host and sintering at a high temperature of 1200 °C resulted in a synergistic effect in enhancing the sinterability and densification of akermanite ceramics. Although varying the Fe3+ content, it was found that similar densification and mechanical properties (i.e., diametral tensile strength, Vickers microhardness and fracture toughness) were observed for the doped ceramics at 1250 °C, indicating that this newly developed formulation is temperature-dependent. Fe3+-doped akermanite ceramics revealed greater in vitro bioactivity as compared to undoped akermanite, demonstrated by better coverage of needle-like apatite precipitates after 21 days of immersion in simulated body fluid. Additionally, Rat-1 cells cultured in direct contact with Fe3+-doped akermanite ceramics showed almost double levels of cell proliferation than their undoped counterpart on both 3 and 7 days of culture. Our finding suggests that 0.9Fe-AK ceramic is a suitable formulation to be considered for future bone substitute material as it provides sufficient mechanical strength as well as good bioactivity and the ability to encourage cell proliferation.


Assuntos
Substitutos Ósseos , Cálcio , Animais , Apatitas , Cerâmica , Ferro , Ratos , Silicatos
3.
J Mech Behav Biomed Mater ; 116: 104379, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33561674

RESUMO

Despite the excellent in vitro and in vivo performance of akermanite ceramic, its poor toughness and strength limit the biomedical application, particularly under load. Herein, the incorporation of strontium enhanced the physicomechanical properties of akermanite and this is ascribed to the decrease in grain size and better sinterability. To investigate the biological performance, the bone-cell interaction with sintered pellets was assessed by in vitro biocompatibility with human fetal osteoblast cell (hFOB). The cell viability using MTT assay revealed that the Ca1.9Sr0.1MgSi2O7 pellets with finer grain size provided better interaction between the cells compared to the unsubstituted counterpart with larger grain size. Our findings highlighted that the synergistic effect of controlled degradation rate and release of Sr2+ into the medium enhanced the in vitro biological properties of akermanite-based materials.


Assuntos
Cerâmica , Estrôncio , Osso e Ossos , Cerâmica/farmacologia , Humanos , Osteoblastos , Estrôncio/farmacologia
4.
Colloids Surf B Biointerfaces ; 159: 445-453, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-28837894

RESUMO

This paper presents a new approach in assembling bone extracellular matrix components onto PLA films, and investigates the most favourable environment which can be created using the technique for cell-material interactions. Poly (lactic acid) (PLA) films were chemically modified by covalently binding the poly(ethylene imine) (PEI) as to prepare the substrate for immobilization of polyelectrolyte multilayers (PEMs) coating. Negatively charged polyelectrolyte consists of well-dispersed silicon-carbonated hydroxyapatite (SiCHA) nanopowders in hyaluronic acid (Hya) was deposited onto the modified PLA films followed by SiCHA in collagen type I as the positively charged polyelectrolyte. The outermost layer was finally cross-linked by 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrocholoride and N-hydroxysulfosuccinimide sodium salt (EDC/NHS) solutions. The physicochemical features of the coated PLA films were monitored via X-ray Photoelectron Spectroscopy (XPS) and Atomic Force Microscope (AFM). The amounts of calcium and collagen deposited on the surface were qualitatively and quantitatively determined. The surface characterizations suggested that 5-BL has the optimum surface roughness and highest amounts of calcium and collagen depositions among tested films. In vitro human mesenchymal stem cells (hMSCs) cultured on the coated PLA films confirmed that the coating materials greatly improved cell attachment and survival compared to unmodified PLA films. The cell viability, cell proliferation and Alkaline Phosphatase (ALP) expression on 5-BL were found to be the most favourable of the tested films. Hence, this newly developed coating materials assembly could contribute to the improvement of the bioactivity of polymeric materials and structures aimed to bone tissue engineering applications.


Assuntos
Materiais Revestidos Biocompatíveis/química , Teste de Materiais/métodos , Membranas Artificiais , Poliésteres/química , Ácido Hialurônico/química , Iminas/química , Microscopia de Força Atômica , Espectroscopia Fotoeletrônica , Polietilenos/química
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