title: Effect of self-association of bovine serum albumin on the stability of surfactant-induced aggregates of allylamine-capped silicon quantum dots.
abstract: The concentration-dependent self-association of bovine serum albumin (BSA) and subsequent altered interaction with sodium dodecyl sulfate (SDS) has been explored by means of photoluminescence (PL) spectroscopy, dynamic light scattering (DLS), circular dichroism (CD), PL imaging, and atomic force microscopy (AFM). By using an extrinsic luminescent probe, allylamine-capped silicon quantum dots (Si-QDs), we have demonstrated the unusual concentration-dependent altered BSA-SDS interaction. Allylamine-capped Si-QDs forms ordered aggregates in the presence of 1 mM SDS due to hydrogen bonding with the surfactants head groups at pH 7.4. Although these aggregates remain stable in the presence of monomeric BSA in the concentration range 1-8 μM, they form typical ring-shaped doughnut-like structures due to "necklace and bead"-like complex formation. However, beyond 10 μM BSA, these aggregates of Si-QDs slowly dissociate and complete dissociation occurs at 150 μM BSA. These anomalous results have been explained by considering the altered hydrophilicity of self-associated BSA.
authors: Discipline of Chemistry, Indian Institute of Technology Indore , M-Block, IET-DAVV Campus, Khandwa Road, Indore 452017, M.P., India.
authors: Surajit
authors: S
authors: Chatterjee
authors: Tushar Kanti
authors: TK
authors: Mukherjee
mesh_terms: D000499:Allylamine / Q000737:chemistry*; D002942:Circular Dichroism; D008027:Light; D018625:Microscopy, Atomic Force; D008855:Microscopy, Electron, Scanning; D045663:Quantum Dots; D012542:Scattering, Radiation; D012710:Serum Albumin, Bovine / Q000737:chemistry*; D012825:Silicon / Q000737:chemistry*; D013050:Spectrometry, Fluorescence; D013501:Surface-Active Agents / Q000737:chemistry*
chemical_list: D013501:Surface-Active Agents; D012710:Serum Albumin, Bovine; D000499:Allylamine; D012825:Silicon