Melt-Electrowritten Poly(L-lactic acid)- and Bioglass-Reinforced biomimetic hydrogel for bone regeneration

Abstract

High-precision poly(L-lactic acid) (PLLA) scaffold fabricated by melt electrowriting (MEW) as a bone substitute was investigated, however, the inherent fragility and the low bioactivity of the scaffold impede its clinical application. In this context, a biomimetic reinforced composite scaffold combining the MEW PLLA lattice with gelatin/genipin/bioglass hydrogel is firstly proposed. Incorporating with 1 wt% bioglass, the composite scaffold shows excellent interconnectivity, high storage modulus (121.3 kPa, 1.3 times of gelatin/genipin) and improved storage modulus (422.3 kPa). Moreover, this reinforced scaffold displays elevated in vitro osteoinduction/conduction capability, high amount of bone tissue formation and a prime Ca/P ratio of 1.69 (as compared with natural bone with Ca/P ratio of 1.67). The mechanisms of the enhanced mechanical properties and the variation of bone formation ability of various scaffolds are elucidated by a potential model. This study gives insights into some potential innovative strategies for using MEW PLLA scaffold to achieve unprecedented results in bone regeneration.