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Interactions between the components of lysozyme/cytochrome c (lysozyme/ Cyt,c) and lysozyme/zein protein mixtures were determined by following the in vitro synthesis of gold (Au) nanoparticles (NPs). Both UV−visible and fluorescence studies were employed to monitor the interactions and simultaneous synthesis of protein coated NPs. Protein coated NPs were characterized by gel electrophoresis and TEM studies. Lysozyme/ Cyt,c complex coated NPs showed remarkable pH responsive behavior due to their amphiphilic nature, while lysozyme/zein complex coated NPs were not pH sensitive because of the predominantly hydrophobic nature. The results were further supported by molecular dynamics studies (MD) of protein−protein interactions and interactions of protein with the gold surface. Molecular simulations helped us to identify the amino acids that drove such interactions. Biological applications of protein coated NPs were determined from hemolytic and antimicrobial studies to demonstrate their potential in pharmaceutical and food industries. The results clearly differentiated between the greater applicability of predominantly amphiphilic lysozyme/Cyt,c complex coated NPs in comparison to predominantly hydrophobic lysozyme/zein complex coated NPs.

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Fundamental aspects of protein complex coated gold nanoparticles (Au NPs) were presented for their possible use in systemic circulation in terms of pharmaceutical formulations. For this purpose, protein complexes of bovine serum albumin (BSA), lysozyme (Lys), and zein with an industrial important bioactive polymer diethylaminoethyl dextran (DEAE) were studied in the presence of Au NPs. Surface adsorption of such complexes magnified DEAE–protein interactions which were easily monitored spectroscopically under the effect of temperature and reaction time. In vitro synthesis of Au NPs allowed a simultaneous adsorption of the DEAE–protein complex on the NP surface to achieve colloidal stability, which was dramatically influenced by the nature of the DEAE–protein complex. The DEAE–BSA complex demonstrated strong favorable mainly electrostatic interactions followed by DEAE–Lys, while DEAE–zein interactions were predominantly influenced by the hydrophobic nature of zein. At the molecular level, the interactions were evaluated from the molecular dynamics (MD) studies which focused on the protein surface charge, dihedral angle variations, and protein unfolding upon dextran–protein complexation as well as its surface adsorption. MD studies further helped us to identify specific amino acid residues which promoted such interactions among the DEAE and protein as well as the surface adsorption of DEAE–protein complexes and allowed the synthesis of suitable biofunctional Au NPs with interesting bioapplicability with blood cells. Biofunctional NPs coated with DEAE–BSA and DEAE–Lys complexes over the entire mixing range proved to be the best suited vehicles for biomedical applications in systemic circulation.

cuanto a la conservación y la mejora ambos modelos necesitán ser mejorados para conseguir un programa de éxito.