Structurally stable and surface-textured polylactic acid/copolymer/poly (ε-caprolactone) blend-based electrospun constructs with tunable hydroxyapatite responsiveness

Abstract

Functionally-designed nanotextured and copolymer (COP) mediated PLA/PCL (70:30 w/w) blend-based interface-engineered electrospun mats (EMs) based constructs, with phase-specific interactions, have been successfully developed. The thermal stability of constructs remained up to ∼300–350 °C, while the crystallinity reduced to ∼12–23 %, indicating enhanced pliability. The tensile strength increased by ∼75 % without much compromise in the tensile modulus whereas the dynamic relaxation response of the constructs shifted to lower temperatures upon the incorporation of ≥ 2.5 phr (parts per hundred parts of resin) of COP. The zeta potential evaluated from radial surface exposure intensity could be manipulated by controlling the extent of COP content (−60 mV for ∼5 phr COP) which in turn led to the dynamics of site-specific charge neutralization driven attachment of Ca2+ ions (∼13 % for ∼5 phr COP) of the nano-hydroxyapatite (n-HA). Such uniformly dispersed, n-HA attached, and surface-decorated (COP ≤ 5 phr) EMs enabled the selective L929 fibroblast cell attachment (∼200 % cell viability for ∼2.5 phr COP). Thus, the approach may prove to augment the biomineralization of Ca and apatite-driven healing kinetics amongst implant-seeking and inflammation-prone sites and thereby, paving a new pathway for controlled and targeted healing of bone, cartilage, dental gums, and other sites demanding n-HA and/or calcium-phosphorus assisted healing mechanism.