Pore Length Effect on Drug Uptake and Delivery by Mesoporous Silicas

The capability of UVM-7 silicas to work as supports for drug storage and delivery is investigated using ibuprofen as a model. UVM-7 silicas are surfactant-assisted synthesised mesoporous materials displaying a characteristic bimodal pore architecture related to their nanoparticulate texture. Strict control of the drug-charge protocol allows the achievement of high ibuprofen loads, not only because of the availability of intra-nanoparticle mesopores and large textural voids, but also owing to the decrease in pore-blocking effects (with regard to related unimodal mesoporous materials such as MCM-41) achieved through the shortening of the mesopore length. The UVM-7/ibuprofen nanocomposites are characterised using XRD, TEM and N2 adsorption/desorption isotherms, and the drug-delivery processes are monitored by spectrometric techniques. The bimodal porosity results in two-stage drug-delivery processes, which are analysed through kinetic models.