Purpose. Biodegradable scaffolds play an important role for a successful tissue regeneration providing the 3-D structure to support cell adhesion, proliferation and differentiation. Among different materials, poly(lactic-co-glycolic) acid (PLGA) is widely used in tissue engineering. The aim of this work was to prepare and characterize a composite PLGA scaffold suitable for bone regeneration. Methods. PLGA Resomer® RG 502H microparticles (MPs) were prepared using the solvent diffusion/evaporation technique. 3-D scaffolds were produced by MP thermal sintering and successively coated with chitosan and alginate. Scaffold macroporosity was investigated using computed tomography (CT) and elaborating data with an open access software. Scaffold degradation was evaluated by in vitro mass loss studies and by gel permeation chromatography (GPC) to determine the polymer molecular weight (Mw) and polydispersity evolution over time. Scaffold mechanical behavior during degradation was evaluated by compressive tests using a loading frame machine. Results. The method used to prepare MPs allowed to obtain MPs (size of about 150 µm) with a high inner porosity. Scaffolds prepared by sintering 200 mg of MPs at 60°C for 1 hour had a structure characterized by suitable mechanical resistance and high porosity (about 87%). In vitro mass loss studies showed the characteristic biphasic mass loss profile, with a low mass loss during the first week and a faster mass loss during the following weeks. At 28 days the residual mass was around 25%. No consistent differences in mass loss rate between bare PLGA and coated PLGA scaffolds were observed. Mw decreased exponentially with increasing the degradation time accordingly to the exponential decay generally reported for this class of polymer. The degradation half time for bare PLGA scaffolds of 2.3 weeks was calculated. During degradation, compressive stress and Young’s Modulus E were higher for coated PLGA scaffolds compared to bare PLGA scaffolds. Conclusions. Sintered chitosan/alginate-coated PLGA scaffolds seem to possess the necessary requirements (e.g., biodegradability, high inner porosity, mechanical properties) to support bone regeneration.
|Titolo:||Physico-chemical and mechanical characterization of biodegradable chitosan/alginate-coated PLGA scaffold for tissue engineering|
|Settore Scientifico Disciplinare:||Settore CHIM/09 - Farmaceutico Tecnologico Applicativo|
|Data di pubblicazione:||mag-2015|
|Enti collegati al convegno:||American Association of Pharmaceutical Scientists (AAPS) Italian University Network (A.It.U.N.)|
|Tipologia:||Book Part (author)|
|Appare nelle tipologie:||03 - Contributo in volume|