Contact angle, WAXS, and SAXS analysis of poly(beta-hydroxybutyrate) and poly(ethylene glycol) block copolymers obtained via Azotobacter vinelandii UWD

Biotechnol Prog. 2005 May-Jun;21(3):959-64. doi: 10.1021/bp050044h.

Abstract

This study investigated and correlated physical properties and cell interactions of copolymers obtained by a poly(ethylene glycol) (PEG)-modulated fermentation of Azotobacter vinelandii UWD. PEGs with molecular weights of 400 and 3400 Da and di(ethylene glycol) (DEG) were used to modulate the bacterial synthesis of poly(beta-hydroxybutyrate) (PHB). The PHB crystallinity was determined by wide-angle X-ray scattering (WAXS). Small-angle X-ray scattering (SAXS) showed that lamellar distances decreased between the PHB and the PHB modulated with PEG or DEG. Furthermore, the contact angle of water on the PHB/PEG polymer surfaces decreased when compared to that of PHB. The significant decrease of the contact angle and corresponding increase in surface tension, as well as significant decrease in cell adhesion, suggest the presence of hydrophilic PEG and DEG within the hydrophobic surface.

Publication types

  • Comparative Study
  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Azotobacter vinelandii / cytology*
  • Azotobacter vinelandii / metabolism*
  • Cell Adhesion / physiology
  • Ethylene Glycols / analysis
  • Ethylene Glycols / chemistry*
  • Hydroxybutyrates / analysis
  • Hydroxybutyrates / chemistry*
  • Macromolecular Substances / analysis
  • Macromolecular Substances / chemistry
  • Materials Testing
  • Molecular Conformation
  • Polyesters / analysis
  • Polyesters / chemistry*
  • Polyethylene Glycols / analysis
  • Polyethylene Glycols / chemistry*
  • Polymers / analysis
  • Polymers / chemistry
  • Surface Properties
  • X-Ray Diffraction / methods

Substances

  • Ethylene Glycols
  • Hydroxybutyrates
  • Macromolecular Substances
  • Polyesters
  • Polymers
  • poly-beta-hydroxybutyrate
  • Polyethylene Glycols
  • diethylene glycol