Synthesis and characterization of poly(3-thiophene methyl acetate)/poly(tetramethylene succinate) nanomembranes. Biocompatibility and biodegradability assays

Abstract

The present study reports the fabrication of free-standing nanomembranes with semiconducting and biodegradable properties. Nanomembranes have been prepared by spin-coating mixtures of a semiconducting polythiophene derivative, poly(3-thiophene methyl acetate), and a biodegradable polyester, poly(tetramethylene succinate). Both the roughness and thickness of the nanomembranes, which ranged from 3 to 20 nm and from 20 to 80 nm, respectively, were precisely controlled through the spin-coater speed and the solvent evaporation properties. Nanomembranes, which are able to retain the properties of the individual polymers, are stable on air and in ethanol solution for more than one year, facilitating their manipulation. Structural and thermal properties of the blends were characterized by Fourier Transform Infrared (FTIR) and Differential Scanning Calorimetry (DSC), respectively. On the other hand, microstructure and phase distribution were analyzed by Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM), which revealed morphology, topography and roughness features Enzymatic degradation essays indicated that the ultra-thin films are biodegradable due to the presence of the aliphatic polyester. Interestingly, adhesion and proliferation assays with epithelial cells revealed that the behaviour of the mixture as cellular matrix is superior to that of the two individual polymers, validating the use of the nanomembranes as possible candidates for bioactive substrates for tissue regeneration.