Poly(D,L-lactide acid, PDLLA) has been researched for scaffolds in bone regeneration. However, its hydrophobocity and smooth surface impedes its interaction with biological fluid and cell adhesion. To alter the surface characteristics, different surface modification techniques have been developed to facilitate biological application. The present study compared two different routes to produce PDLLA/superhydrophilic vertically aligned carbon nanotubes:nanohydroxyapatite (PDLLA/VACNT-O:nHAp) scaffolds. For this, we used electrodeposition and immersion in simulated body fluid (SBF). Characterization by goniometry, scanning electron microscopy, X-ray diffraction, and infrared spectroscopy confirmed the polymer modifications, the in vitro bioactivity, and biomineralization. Differential scanning calorimetry and thermal gravimetric analyses showed that the inclusion of VACNT-O:nHA probably acts as a nucleating agent increasing the crystallization rate in the neat PDLLA without structural alteration. Our results showed the formation of a dense nHAp layer on all scaffolds after 14 days of immersion in SBF solution; the most intense carbonated nHAp peaks observed in the PDLLA/VACNT-O:nHAp samples suggest higher calcium precipitation compared to the PDLLA control. Both cell viability and alkaline phosphatase assays showed favorable results, because no cytotoxic effects were present and all produced scaffolds were able to induce detectable mineralization. Bone defects were used to evaluate the bone regeneration; the confocal Raman and histological results confirmed high potential for bone applications. In vivo study showed that the PDLLA/VACNT-O:nHAp scaffolds mimicked the immature bone and induced bone remodeling. These findings indicate surface improvement and the applicability of this new nanobiomaterial for bone regenerative medicine.

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A nanocomposite of poly(ether ether ketone) (PEEK) with 10 wt % hydroxyapatite (HA) was produced by extrusion and injection molding. Afterward, the samples were thermally treated. Thermal and short‐ and long‐term mechanical characterizations of the samples were made. The adhesion of human adipose stem cells (h‐ASCs) on the samples was also monitored. The ultimate tensile strength (UTS) and elastic modulus values of the nanocomposite were found to be much higher than those of trabecular bone. The impact strength of PEEK was not modified by HA; this suggested that there was no formation of large agglomerates of nanoparticles that could concentrate the stresses. With regard to fatigue life, both the thermally and nonthermally treated nanocomposites did not fail after 106 cycles when maximum stresses of 30 and 50% of the UTS were applied, but they failed when the maximum applied stress was 75% of the UTS and behaved as cortical bone. After 5 days of culturing, the h‐ASCs had a higher proliferation in the nanocomposite than in pure PEEK because of the presence of HA. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41748.

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