Monodisperse protein stabilized gold nanoparticles via a simple photochemical process

Protein stabilized, water soluble gold nanoparticles are essential for biomedicines and biotechnology. Bovine Serum Albumin (BSA) is one of the most abundant proteins. It has a remarkable ability of binding and transporting materials across cell membrane that makes it ideal for drug delivery and very useful for pharmaceutical industry. Herein, we explored the direct synthesis of BSA stabilized gold nanoparticles via a simple photochemical process. BSA stabilized gold nanoparticles are synthesized in one step, using Irgacure (I-2959) as photoinitiator. UV radiation facilitates the easy one step synthesis of protein stabilized gold nanoparticles without any denaturation of the protein, during the process. Polyacrylamide Gel (PAGE) shows that there is no difference in the bands height and mobility of native BSA and UV irradiated BSA. PAGE results are further confirmed by fluorescence spectroscopy of native and UV irradiated BSA. BSA/PEG (polyethylene glycol) mixed monolayer stabilized gold nanoparticles have also been prepared in one step using the photochemical process. Different ratios of PEG to BSA are used to evaluate the particle size and the size distribution of gold nanoparticles. Transmission electron microscope (TEM) and dynamic light scattering (DLS) confirm the presence of nearly monodisperse mixed layer stabilized gold nanoparticles.