The Study On The Interaction Mechanism Between Bovine Serum Albumin And Gold Nanoparticles

According to the development of nanotechnology, due to its excellent physical and chemical properties, nanoparticles have attracted more and more attention from sciences to industries. However, when the functional nanoparticle apply into the vivo, the protein will rapidly absorbed on the surface of nanoparticle, formed nanoparticles-protein crown structure. Results in a change nanoparticles pre-designed function. Therefore, to explore the interaction between proteins and nanoparticles play an important role for the functional nanoparticles in vivo. In this paper, we set bovine serum albumin as an example, through completely digesting the BSA molecules adsorbed on the AP-AuNPs (gold nanoparticles) with proteases, and in combination with both PAGE (polyacrylamide gel electrophoresis) and the MALDI-TOF-MS (matrix-assisted laser desorption/ionization-time-of-flight-mass spectrometry), we discovered a 107-amino-acid long peptide (12.8 kDa) acting as the "binding site" of the discrete AP-AuNP-BSA conjugates. To make sense of how the AP-AuNP surface accommodating and protecting such a long peptide from protease’s digesting, a novel mechanical mortise and tenon binding mode was proposed, in which the binding peptide acted as the tenon tongue to insert into the mortise hole of hydrophobic grooves on the surface of AP-AuNPs. We selected bovine hemoglobin (Hgb), molecular weight less than BSA, connected by way of chemical link, useing of molecular sieve and dynamic light scattering colorimeter two ways to authenticate the possibility of the model, While a small molecule ibuprofen, SDS compete with BSA binding gold nanoparticles to progress prove the correctness of the model.