First principles study on the potential of functionalized porous silicon to capture adverse agents to human health: The role played by the interface interactions

Porous Silicon (PSi) is an ideal material to build biosensors due to its large surface area and biocompatibility. However, it lacks of selectivity. By adhering bilayer lipids, active sites are added for vital biochemical processes. Such processes are promoted by different proteins, which aid to detect pollutants and drugs, among other. The present work is a systematic theoretical study at the density functional theory level on PSi models, functionalized with -H and -OH. Several concentrations of such functional groups were assessed at the pores to elucidate the reactivity via Fukui indexes of electrophilic and nucleophilic attack. The 1,2-dimyristoyl-sn-glycero-3-phospho-choline(DMPC) lipid was used as a probe system to interact with the PSi. The attraction was evaluated as electrostatic with a van der Waals contribution. The adsorption was highly selective to the degree of function-alization at the pore. The PSi facets (100) and (001) showed different mechanisms of interaction with the DMPC lipid. The theoretical absorption spectra addressed that the DMPC lipid could be identified with intensity vari-ations coming from the degree of functionalization at the pore, which may be further rationalized experimen-tally. The present methodology may aid to tailor novel materials to capture and identify adverse agents present in the environment.

Automated summary

Porous silicon (PSi) has been investigated as a biosensor material due to its large surface area and biocompatibility. In this study, the authors conducted a theoretical investigation on PSi models functionalized with -H and -OH, using density functional theory. The results showed that the adsorption of a DMPC lipid on PSi was highly selective, depending on the degree of functionalization at the pore. The absorption spectra could be used to identify the degree of functionalization, which may have practical applications in capturing and identifying adverse agents in the environment.