Interaction of Bovine Serum Albumin with Chrysotile: Spectroscopic and Morphological Studies

• Published in: Chemistry : a European journal 2006-02, Vol.12 (7), p.1968-1974
• Main Authors: Falini, Giuseppe, Foresti, Elisabetta, Lesci, Isidoro G., Lunelli, Bruno, Sabatino, Piera, Roveri, Norberto
• Format: Article
• Language: English
• Subjects: adsorption; asbestos; Asbestos, Serpentine - chemistry; chrysotile; Indicators and Reagents; Microscopy, Atomic Force; Microscopy, Electron, Transmission; nanocrystals; Nanoparticles; protein modifications; Protein Structure, Secondary; Serum Albumin, Bovine - chemistry; Spectroscopy, Fourier Transform Infrared; Surface Properties
• ISSN: 0947-6539; 1521-3765
• DOI: 10.1002/chem.200500709

The biodurability of chrysotile fibers, which is related to their cytotoxicity and mutagenic responses, is strongly affected by the surface chemical adsorption of biological molecules. Natural chrysotile is a heterogeneous material in both structure and composition. The availability of synthetic stoichiometric chrysotile of constant structure and uniform morphology has allowed us to investigate its interaction with bovine serum albumin (BSA). By using transmission electron microscopy (TEM) and atomic force microscopy (AFM), we have obtained the first morphological evidence of albumin adsorption onto chrysotile nanocrystals. FTIR spectroscopy was used to quantify modifications of BSA secondary structure that were induced by the surface interaction. The protein transition to β‐turns allows a stronger interaction between the protein hydrophilic side‐chains and the charged asbestos surface, which is consistent with hydrogen bonds involving the superficial OH groups. Synthetic stoichiometric chrysotile nanocrystals were shown to be an ideal reference standard with which to study the interaction of asbestos fibers with biological systems, in order to elucidate the chemical mechanisms of asbestos toxicity. Asbestos absorbs albumin: The first morphological evidence of BSA adsorption onto synthetic chrysotile nanocrystals—an ideal reference standard with which to study the interaction of asbestos fibers with biological systems—is revealed by results of TEM and AFM analysis (TEM image shown). FTIR investigation of the adduct allowed quantification of albumin secondary‐structure modifications induced by the electron‐donor sites present on the nanocrystal surface.