Direct Conjugation of Semiconductor Nanoparticles with Proteins

• Published in: Langmuir 2005-03, Vol.21 (5), p.2008-2011
• Main Authors: Meziani, Mohammed J, Pathak, Pankaj, Harruff, Barbara A, Hurezeanu, Razvan, Sun, Ya-Ping
• Format: Article
• Language: English
• Subjects: Animals; Cadmium Compounds - chemistry; Cattle; Chemistry; Colloidal state and disperse state; Exact sciences and technology; General and physical chemistry; Microscopy, Atomic Force; Microscopy, Electron, Transmission; Nanostructures - chemistry; Nanostructures - ultrastructure; Physical and chemical studies. Granulometry. Electrokinetic phenomena; Semiconductors; Serum Albumin, Bovine - chemistry; Sulfides - chemistry; X-Ray Diffraction
• ISSN: 0743-7463; 1520-5827
• DOI: 10.1021/la0478550

Nanocrystalline CdS particles directly conjugated with bovine serum albumin (BSA) protein were prepared by applying the supercritical fluid processing technique, rapid expansion of a supercritical solution into a liquid solvent. The direct conjugation takes advantage of the unique features of the process for nanoparticle formation. The BSA-conjugated CdS nanoparticles in stable aqueous suspension or in the solid state were characterized by using microscopy, X-ray diffraction, and optical spectroscopy methods. The results show that well-dispersed CdS nanoparticles are coated with BSA in a core−shell-like arrangement and that the protein species associated with the nanoparticles remain functional according to the modified Lowry assay. These BSA-conjugated CdS nanoparticles are also strongly luminescent, with the luminescence spectrum contributed to primarily by the exciton emission.