Novel polydopamine/halloysite nanotubes reinforced brushite calcium phosphate cement for bone regeneration with synergistic regulation mechanical/osteogenic capacity

Abstract

Bone regeneration remains a clinical challenge with limited bone substitutes. Brushite Calcium phosphates cements (Bru-CPCs), possessing good bioactivity and biocompatibility, are one of widely studied for bone graft materials. However, their further application in the long-term remodeling of bone were limited by the low compressive strength. Adding additives have been promising strategy to solve the above problem. Herein, halloysite nanotubes (HNTs) with its unique rod-like structure and excellent biocompatibility, were chosen as reinforced materials to fabricate bone repair materials. Inspired by the adhesive proteins in mussels, we modified HNTs surface with polydopamine (PDA) to improve the inorganic-inorganic phase interfacial interactions between HNTs and Bru-CPCs. Bru-CPCs, Bru-CPCs/1.5%HNTs and Bru-CPCs/1.5%HNTs@PDA were fabricated and the mechanical properties and biological activity of bone repair materials were evaluated in detail. All the results indicated that Bru-CPCs incorporated with 1.5 wt% HNTs@PDA has good compressive strength and osteo-differentiation properties, which will be a prospective biomaterial for bone-tissue repair.