Ferricytochrome c encapsulated in silica nanoparticles: Structural stability and functional properties
Articolo
Data di Pubblicazione:
2004
Citazione:
Ferricytochrome c encapsulated in silica nanoparticles: Structural stability and functional properties / G. Fiandaca, E. Vitrano, A. Cupane. - In: PEPTIDE SCIENCES. - ISSN 0006-3525. - 74:1-2(2004), pp. 55-59. ((Intervento presentato al 10. convegno European Conference on the Spectroscopy of Biological Molecules (ECSBM 2003) tenutosi a Szeged nel 2003.
Abstract:
Using a modified sol-gel technique, we have succeeded in encapsulating ferric cytochrome c in silica nanoparticles obtained from hydrolysis and polycondensation of tetramethylorthosilicate. Particles dimensions have been determined with dynamic light scattering; this technique yields an hydrodynamic radius of about 100 nm, each nanoparticle containing about 10(2) - 10(3) proteins. If stored in the cold at low ionic strength, nanoparticles are stable for more than one week, even if a slow radius increase with time is observed. CD measurements show that encapsulated proteins exhibit substantially increased stability, against guanidinium hydrochloride induced denaturation, Reduction kinetics of encapsulated ferric cytochrome c by sodium dithionite, measured with standard stopped flow techniques, are slower by a factor of ten with respect to those measured in solution. Analogous experiments with myoglobin suggest that this slowing down is due to the diffusion time of dithionite within the silica matrix. Indeed, fa smaller ligand like CO is used, the intrinsic kinetic properties of encapsulated proteins are found to be unaltered even in the millisecond nine range. The reported data show that our nanoparticles are extremely useful both for basic research, to study the stability and functions of encapsulated proteins, and for their potential biotechnological applications.
Tipologia IRIS:
01 - Articolo su periodico
Keywords:
sol-gel encapsulation; protein denaturation; dynamic light scattering; kinetic properties; biosensors
Elenco autori:
G. Fiandaca, E. Vitrano, A. Cupane
Link alla scheda completa: