Poly(3-hydroxybutyrate-co-3-hydroxyvalerate)/poly(e-caprolactone) blends for tissue engineering applications in the form of hollow fibres

In this work, hollow fibers to be used as guides for tissue engineering applications were produced by dry-jet-wet spinning of poly(3-hydroxybutyrate-co-3-hydroxyvalerate)/poly(e-caprolactone) (PHBHV/PCL) solutions in chloroform with various weight ratios between the components (PHBHV/PCL 100/0; 80/20; 60/40; 50/50; 40/60; 20/80; 0/100 w/w). Fibers obtained from PHBHV/PCL blends had a low degree of surface and bulk porosity, depending on composition. Physico-chemical characterisation involving scanning electron microscopy (SEM) and differential scanning calorimetry (DSC) showed that PHBHV/PCL blends are compatible. Interactions between blend components were studied by Fourier transform infrared total reflectance spectroscopy (FTIR-ATR), DSC analysis and polarised optical microscopy analysis. Homogeneity of blend composition was assessed by IR-Chemical Imaging analysis. PHBHV/PCL samples were found to be weakly hydrophilic and their biocompatibility was proved by in vitro tests using mouse fibroblasts. Mechanical properties of PHBHV/PCL blends were investigated by stress-strain tests, showing an increasing ductility of blend samples with increasing the PCL amount. Hollow fibres supported fibroblasts attachment and proliferation depending on composition and porosity degree.