| dc.description.abstract | Porous silicon (pSi), with its nanoscale architecture, acts as a promising resorbable biomaterial for a broad variety of applications: biosensors, orthopedic tissue engineering, and controlled drug delivery. The most conventional methods for preparing porous silicon particles are anodization of silicon wafers and metal-assisted chemical etching (MACE). These established techniques require elemental crystalline silicon feedstocks, and the use of corrosive hydrofluoric acid (HF) and organic solvents. Rather than employing these methods, we have developed an eco-friendly alternative of producing pSi from silicon accumulator plants/agriculture waste. Two different silicon accumulator plants Bambuseae (tabasheer) and Equisetum telmateia (great horsetail)have been investigated for this purpose, and high surface area porous silicon nanostructures prepared using a magnesiothermic reduction of silica isolated from these plants.^This fabrication process of pSi includes extraction of biogenic silica from the ground plant by calcination, followed by reduction with magnesium, and purification of reduced Si product. Details of fabrication process and characterization of pSi powders by a combination of scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX), X-ray diffraction (XRD), transmission electron microscopy (TEM), and low temperature nitrogen gas adsorption measurements will be outlined in this presentation. As pointed out above, Bambuseae serves as a viable eco-friendly starting materials for fabricating porous silicon (pSi).At the same time, if the selected plant leaf components contain medicinally-active species (antibacterial) as well, then the single substance can provide not only the nanoscale high surface area drug delivery carrier, but the drug itself.^With this idea in mind using a single plant source (Bambuseae) we have developed porous silicon based drug delivery carrier matrix for the sustained release of antibacterials. Nanoentrapment of vitamins, nutrients, and plant based therapeutics is another attractive area in food and pharmaceutical industries to address the challenges of stability and bioavailability of entrapped agents. One way to increase the bioavailability of the drugs is by enhancing their solubility. We have evaluated the ability of nanostructured plant-derived porous silicon particles (pSi) as potential candidates to increase the solubility of plant extracts rich in therapeutic polyphenolic compounds (Equisetum arvense) and a poorly water soluble vitamin (vitamin d3). We have also evaluated the ability of plant derived porous silicon nanoparticles (pSiNPs) as gene delivery vehicles.^Following necessary reduction of pSiNP particle size and functionalization with primary amine moieties at the nanoparticle surface, the binding of a reporter plasmid DNA, pEF1-eGFP (endothelial factor 1 enhanced green fluorescent protein, 6429 bp) to the pSiNPs was investigated, followed by attempted transfection of HEK293 cells. | |
