Hierarchical Porous Composites For Dual-drug Release

With simple synthetic process, adjustable aperture, higher specific surface area andfunctional surface, mesoporous material has been the hotspot in materials science.However, with the development of materials, the single-pore channel and singlecomposition of mesoporous materials can not meet the research needs. In this paper, wesynthesized hierarchical porous structure on multiple drug delivery property.With PD and PSS polyelectrolytes coated SBA-15as the carrier of drug metforminhydrochloride (MH), composite porous silica as the carrier of ibuprofen (IBU), twodrugs carrier assembly then synthesis of dual-drug delivery systems. In the deliverysystem, MH from polyelectrolytes coated SBA-15in acid condition and the release ofIBU from MMC in alkaline environment. The results show that the model drug can becontrolled release with the change of pH value of the environment in dual-drug deliverysystems.Using electrostatic spinning method, the PLGA@IBU composite materials withfiber structure were prepared. And then, these fibers were immerged in SBF to inducethe hydroxyapatite(HAP) inorganic shell on the surface layer. After adsorption ofmetformin hydrochloride (MH) on the surface, the DDDS was obtained. The drugrelease behavior was investigated in phosphate butter solution (PBS) pH=7.4. MHreleased freely from the surface of hydroxyapatite layer due to adsorption between MHand Hap, while IBU released from the inner of fibers with the biodegradation of PLGA,thereby achieved dual-drug delivery systems.St ber spheres was used as template, and then coated with silica shell, afteraddition of APTES in the system. After removing of St ber spheres by etching methodwith sodium carbonate as etching agent, the hollow silica was obtained. Calcinationunder400oC make the alkyl amine from APTES was carbonized. That brings somecarbon impurities in the silica network making the fluorescent property of mesoporoushollow silica materials.