Calcium phosphate ceramics-loaded polysulfone scaffolds by additive manufacturing for bone repair

Polysulfone (PSU) is a high-performance engineering polymer with great potential for bone reconstruction. PSU processing through additive manufacturing (AM) has emerged as a modern method to develop surgical implants for tissue repair. The purpose of this study was to explore the potential of AM to fabricate PSU scaffolds loaded with bioactive ceramics, specifically synthetic hydroxyapatite (HA) or β-tricalcium phosphate (β-TCP) at two distinct concentrations (5 and 10 % wt). For this purpose, an AM protocol involving the extrusion and controlled deposition into an ethanol bath of a suspension of ceramic particles in a PSU/1-methyl-2-pyrrolidinone solution was developed. The scaffolds fabricated had interconnected macroporous architecture, with fiber diameter increasing and pore size decreasing when HA or β-TCP was loaded at a 5 % wt concentration. The loading of the two ceramics did not affect the mechanical parameters of the scaffold, except for the case of β-TCP loading at 10 % wt, which resulted in decreased tensile and compressive modulus and strength. However, in vitro experiments revealed that β-TCP loading led to a more rapid increase in murine pre-osteoblast cell metabolic activity and differentiation, as well as a more extensive cell colonization of the scaffold . In-silico investigation was used to determine the binding energies of HA and β-TCP with Alkaline Phosphatase (ALP). Pharmacokinetics and toxicity of the compounds were also determined using Pharmacokinetic Characteristics and Structure Modeling (pkCSM). Taken together, the findings obtained indicate that the PSU scaffold loaded with 5 % wt β-TCP is a promising candidate for future bone engineering research.