Influence of Diol Chain Length on Various Properties of Citric Acid Polyesters/PLA Electrospun Nonwovens for Tissue Engineering Applications

Abstract

Despite the great potential of citrate polyesters in regenerative medicine, the data about their application in electrospinning is somewhat limited. In this work, poly(dimethylene citrate) (P-1,2-ECit), poly(tetramethylene citrate) (P-1,4-BCit), and poly(hexamethylene citrate) (P-1,6-HCit) were synthesized. Nonwovens from poly(diol citrates)/PLA mixtures were successfully electrospun and characterized using SEM, AFM, water contact angle measurement, DSC, TGA, and in vitro degradation tests. The addition of poly(diol citrates) increases the hydrophilicity and surface adhesion force of PLA nonwovens; however, the observed effects depend on the scale level (macro/micro) of the analysis. Diol chain length in poly(diol citrate) influences the compatibility and heterogeneity of its distribution within the carrier polymer. Additionally, it impacts the crystallinity of the PLA phase. Degradation tests show the problem of the nonwoven stability in the aqueous media and the high leachability of the short-chained poly(diol citrates). Addressing this issue is important regarding controlling the degradation kinetics. Despite the good processability in electrospinning and promising surface properties of the poly(diol citrates)/PLA mixtures, the instability of these materials in an aqueous environment is an important issue which can subsequently affect the performance of the eventual implant/cell scaffold. The solution may involve chain elongation of the hydrophilic oligomeric additive.