Polycaprolactone scaffolds prepared by 3D printing electrosprayed with polyethylene glycol-polycaprolactone block copolymers for applications in bone tissue engineering

Abstract

Additive manufacturing technologies and their ability to produce customized items have gained interest in different fields, such as in the design of personalized scaffolds for tissue engineering applications. Although different materials and printers are available in the market, fused filament 3D printers are common and accessible to any user, and, in addition, some commercially available filaments are potentially biocompatible. In this sense, polycaprolactone (PCL) stands out for bone tissue engineering owing to its biocompatibility and appropriate thermal and mechanical properties. In this work, we present the designing, printing, and characterization of 3D porous scaffolds obtained using a free software for 3D printing, a commercial 3D printer, and PCL filament. The printed scaffolds presented adequate porosity (60 %), with pores of around 500 μm, and mechanical properties (compressive modulus of 91 MPa) to be used in bone tissue engineering, low wettability, and a smooth, regular surface. As these two last characteristics may jeopardize an adequate cellular response towards the adhesion and mineralization of the scaffolds, the 3D printed PCL objects were submitted to electrospraying with different poly(ethylene glycol)/PCL block copolymers (PEGm-b-PCLn), showing different hydrophobic/hydrophilic balance, resulting in a rough layer covering the surface of the printed scaffolds. This layer preserves the macrostructure and mechanical characteristics of the scaffolds and allows tuning material surface roughness and hydrophilia. All PCL3D scaffolds allowed osteogenic induction, and the coated scaffolds, showing a rough surface, allowed calcium deposition at day 14.