Wettability and surface charge of Si3N4-bioglass composites in contact with simulated physiological liquids

• Type: Article in International Scientific Journal
• Date: 2002

Authors

M. Amaral (Author) Other; Maria Ascensão Lopes (Author) FEUP; José D. Santos (Author) FEUP; R. F. Silva (Author) Other

Journal

Title: Biomaterials

Vol. 23 No. 24

Pages: 4123-4129

ISSN: 0142-9612

Publisher: Elsevier

Indexing

ISI Web of Knowledge - 39 Citations

ISI Web of Science

Scopus - 43 Citations

COMPENDEX

Scientific classification

FOS: Engineering and technology > Environmental biotechnology

Other information

Authenticus ID: P-000-MRX

DOI: 10.1016/s0142-9612(02)00155-2

Abstract (EN): Wettability and surface charge studies were performed on a novel Si3N4-30 wt% bioglass biocomposite. Contact angle and surface tension variation with time were determined at 25 degreesC, respectively, by the sessile and pendant drop techniques, for distinct testing liquids: water, diiodomethane, simulated body fluid (SBF) and bovine serum albumin (BSA) dissolved in SBF solution. This biocomposite revealed a hydrophilic character (theta = 26.6 +/- 2.0degrees) and a surface tension value (66.6 mJ m(-2)) comparatively higher than those of the most common bioceramics. An important characteristic is the high work of adhesion towards SBF+BSA (96.4+/-0.2 mJ m(-2)) that was measured. The Si3N4-bioglass material is negatively surface charged above the pH(IEP)=2.5 in aqueous SBF+BSA solution, as a result of the presence at the surface of unsaturated Si-O bonds and Si-OH groups. The very high negative zeta potential at pHsimilar to7 (-58.6+/-5.5mV) influenced albumin adsorption and mechanisms are discussed in terms of entropy and enthalpy gains from conformational unfolding and cations coadsorption.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 7