Drisko G.L.,Particulate Fluids Processing Center |
Zelcer A.,Comision Nacional de la Energia Atomica |
Zelcer A.,National University of General San Martín |
Wang X.,CSIRO |
And 3 more authors.
ACS Applied Materials and Interfaces | Year: 2012
Herein, we report a one-pot synthesis of crack-free titania monoliths with hierarchical macro-mesoporosity and crystalline anatase walls. Bimodal macroporosity is created through the polymer-induced phase separation of poly(furfuryl alcohol). The cationic polymerization of furfuryl alcohol is performed in situ and subsequently the polymer becomes immiscible with the aqueous phase, which includes titanic acid. Addition of template, Pluronic F127, increases the mesopore volume and diameter of the resulting titania, as the poly(ethylene glycol) block interacts with the titania precursor, leading to assisted assembly of the metal oxide framework. The hydrophobic poly(propylene glycol) micelle core could itself be swollen with monomeric and oligomeric furfuryl alcohol, allowing for mesopores as large as 18 nm. Variations in synthesis parameters affect porosity; for instance furfuryl alcohol content changes the size and texture of the macropores, water content changes the grain size of the titania and Pluronic F127 content changes the size and volume of the mesopore. Morphological manipulation improves the photocatalytic degradation of methylene blue. Light can penetrate several millimeters into the porous monolith, giving these materials possible application in commercial devices. © 2012 American Chemical Society.
Go D.P.,Particulate Fluids Processing Center |
Go D.P.,University of Melbourne |
Gras S.L.,Particulate Fluids Processing Center |
Gras S.L.,University of Melbourne |
And 6 more authors.
Biomacromolecules | Year: 2011
Tissue regeneration may be stimulated by growth factors but to be effective, this delivery must be sustained and requires delivery vehicles that overcome the short half-life of these molecules in vivo. One promising approach is to couple growth factors to the biomaterial surface so that they are readily bioavailable. Here the layer-by-layer process was used to construct a multilayered polyelectrolyte delivery system on the surface of poly(lactic-co-glycolic) acid constructs. The system was first optimized on a planar surface before translation to a 3D microsphere system. The layers incorporated heparin to facilitate the loading of basic fibroblast growth factor and increase growth factor stability. Cross-linked capping layers also reduced any burst release. The model growth factor was released in a sustained manner and stimulated significantly higher cell proliferation in vitro on release compared with the addition of the growth factor heparin complex free in solution, demonstrating the promise of this approach. © 2011 American Chemical Society.