Effect of Sr, Mg and Fe substitution on the physico-chemical and biological properties of SiCaP multilayer scaffolds

In this work, a new combination of ceramic materials is proposed for bone tissue engineering applications. Multilayer scaffolds consisting of a core composed mainly of calcium pyrophosphate and external coatings of silica and calcium doped with Fe³⁺, Sr²⁺ and Mg²⁺ were prepared. To study the influence of the arrangement of dopant ions in the external coatings, two different scaffolds were developed: scaffolds 3J consisting of a single external coating with 9 mol% of Fe³⁺, Sr²⁺ and Mg²⁺ ions; and scaffolds 3S comprising three external coatings, each containing 3 mol% of Fe³⁺, Sr²⁺ and Mg²⁺ ions. Scaffolds were physico-chemically characterized and evaluated for in vitro bioactivity and cellular response in the presence of MG-63 cells. The results showed that the core scaffold displayed no in vitro bioactivity or good cellular response, but served as a support for the external coatings given its mechanical resistance. The cell viability of scaffolds 3J and 3S increased more than 100% in relation to the core, and also improved cell proliferation and adhesion resulting in a dense layer of cells that covered the scaffolds’ entire surface. The arrangement of ions in the external coatings did not influence the cellular response, but determined the bioactivity rate.