Novel hydroxyapatite (HA) dual-scaffold with ultra-high porosity, high surface area, and compressive strength

A novel scaffold designed for tissue engineering applications, which we refer to as a "dual-scaffold" because its structure consists of two interlaced three-dimensional (3-D) hydroxyapatite (HA) networks, was fabricated using a combination of the rapid prototyping (RP) method and dip-coating process. To accomplish this, a graphite network acting as a template was prepared using the RP method and then uniformly dip-coated with HA slurry. The resultant sample was then heat-treated at 1250 degrees C for 3 h in air to remove the graphite network and consolidate the HA networks. An additional 3-D channel was formed by removing the graphite network, while preserving the pre-existing channel. The unique structure of the dual-scaffold endows it with unprecedented features, such as ultra-high porosity (>85%), a high surface area and high compressive strength, as well as a tightly controlled pore structure. In addition, an excellent cellular response was observed to the fabricated HA dual-scaffold.