Functionalized porous silicon oxidation in simulated gastric and intestinal fluids

CHED 318

Jake T. Lee, porterl@wabash.edu, Nick Molby, and Lon A. Porter Jr. Department of Chemistry, Wabash College, Crawfordsville, IN 47933
Porous silicon chips were prepared via electrochemical etching and functionalized with C6 or C18 monolayers. Functionalization was accomplished through a surface hydrosilylation reaction by thermal, microwave, Lewis acid, and carbocation mediated pathways. Functionalized chips were exposed to a four hour immersion in simulated gastric fluid, followed immediately by an eighteen hour exposure to simulated intestinal fluid in order to monitor the degradation of the monolayer and underlying silicon substrate if passed through the gastrointestinal tract. Both enzyme and enzyme-free environments were investigated. Sample oxidation was tracked using semiquantitative FTIR analysis. Initial results indicate that the thermal and microwave hydrosilylation routes yield the most robust monolayers and produce more durable chips in comparison to unfunctionalized control samples.