Bioactivity test for amine-based functionalized meso- and macro-porous silicon substrates

The properties of porous silicon (PSi) make this material very useful for biophysical applications. In this work, bioactivity tests are reported in meso- and macro-porous silicon substrates, before and after amine-based functionalization treatments. Two biofunctionalization methods were used: thermally activated chemical vapour deposition (TA-CVD) and immersion in organic solutions. In both techniques 3-aminopropyltriethoxysilane was used as precursor. The bioactivity tests consisted in the incubation of the substrates in a simulated body fluid to check the nucleation of calcium phosphate on the surface and in the evaluation of Aspergillus fungi growth on different substrates. ctionalization methods change the bioactive behaviour of the substrates regarding to both Ca-phosphate precipitation and fungi growth. Meso-porous silicon, which is bioactive as raw fresh material, highly improves its bioactivity after biofunctionalization. On the other hand, macro-porous silicon, which shows no bioactivity when tested as fresh material, turns out to be bioactive after biofunctionalization. Fungi development changed in PSi substrates according to the functionalization treatments from promoted growth (immersion) to completely inhibited growth (TA-CVD).