Study of diffusional properties of silicone matrices for drug bioavailability modulation

Modified silicone elastomers were synthesized by grafting an organic pendent segment (allylglycidylether) along polydimethylsiloxane chains. The effects of the degree of grafting were evaluated with respect to drug solubility, diffusivity and elastomer properties. It was found that this elastomer modification led to a high increase in solubility for a lipophilic steroid (progesterone) and a more hydrophilic drug (metronidazole). Drug diffusivities were not highly reduced; permeability and release properties of these modified silicone networks could also be widely improved not only for steroids but also for more hydrophilic drugs.