Mesoporous bioactive glasses (MBGs) with a compoisition of 85SiO 2 -10CaO-5P 2 O 5 (mol %) have been prepared through the evaporation-induced self-assembly (EISA) method, using P123 as a structure directing agent. For the first time, SiO 2 -CaO-P 2 O 5 MBGs with identical composition and textural properties, but exhibiting different bicontinuous 3D-cubic and 2D-hexagonal structures, have been prepared. These materials allow us to discriminate the role of the structure on the bioactivity, from other parameters. To understand the role of each component on the mesostructure, local environment, and bioactive behavior, mesoporous 100SiO 2 , 95SiO 2 -5P 2 O 5 , and 90SiO 2 -10CaO (mol %) materials were also prepared under the same conditions. The results demonstrate that the joint presence of CaO and P 2 O 5 results in amorphous calcium phosphate (ACP) clusters sited at the pore wall surface. This heterogeneity highly improves the bioactive behavior of these materials. In addition, the presence of ACP clusters within the silica network leads to different mesoporous structures. The mesoporous order can be tuned through a rigorous control of the solvent evaporation temperature during the mesophase formation, resulting in p6mm, p6mm/Ia3d coexistence, and Ia3d phases for 20, 30, and 40°C, respectively. Preliminary results indicate that, in the case of identical composition and textural properties, the mesoporous structure does not have influence on the apatite formation, although initial ionic exchange is slightly enhanced for 3D cubic bicontinuous structures.

Multifunctional 3D nanocomposite scaffolds with the ability for loading and sustained delivery of an antimicrobial agent, to eliminate and prevent bone infection and at the same time to contribute to bone regeneration process without cytotoxic effects on the surrounding tissue has been proposed. These 3D scaffolds exhibit a sustained levofloxacin delivery at physiological pH (pH 7.4), which increasing notably when pH decreases to characteristic values of bone infection process (pH 6.7 and pH 5.5). In vitro competitive assays between preosteoblastic and bacteria onto the 3D scaffold surface demonstrated an adequate osteoblast colonization in entire scaffold surface together with the ability to eliminate bacteria contamination.

The decellularized extracellular matrix (ECM) obtained from human and porcine adipose tissue (AT) is currently used to prepare regenerative medicine bio-scaffolds. However, the influence of these natural biomaterials on host immune response is not yet deeply understood. Since macrophages play a key role in the inflammation/healing processes due to their high functional plasticity between M1 and M2 phenotypes, the evaluation of their response to decellularized ECM is mandatory. It is also necessary to analyze the immunocompetence of macrophages after contact with decellularized ECM materials to assess their functional role in a possible infection scenario. In this work, we studied the effect of four decellularized adipose matrices (DAMs) obtained from human and porcine AT by enzymatic or chemical methods on macrophage phenotypes and fungal phagocytosis. First, a thorough biochemical characterization of these biomaterials by quantification of remnant DNA, lipids, and proteins was performed, thus indicating the efficiency and reliability of both methods. The proteomic analysis evidenced that some proteins are differentially preserved depending on both the AT origin and the decellularization method employed. After exposure to the four DAMs, specific markers of M1 proinflammatory and M2 anti-inflammatory macrophages were analyzed. Porcine DAMs favor the M2 phenotype, independently of the decellularization method employed. Finally, a sensitive fungal phagocytosis assay allowed us to relate the macrophage phagocytosis capability with specific proteins differentially preserved in certain DAMs. The results obtained in this study highlight the close relationship between the ECM biochemical composition and the macrophage’s functional role.