title: Quantification of the CBD-FITC conjugates surface coating on cellulose fibres.
abstract: BACKGROUND
  Cellulose Binding Domains (CBD) were conjugated with fluorescein isothiocyanate (FITC). The surface concentration of the Binding Domains adsorbed on cellulose fibres was determined by fluorescence image analysis.
  
  
  RESULTS
  For a CBD-FITC concentration of 60 mg/L, a coating fraction of 78% and 110% was estimated for Portucel and Whatman fibres, respectively. For a saturating CBD concentration, using Whatman CF11 fibres, a surface concentration of 25.2 x 10-13 mol/mm2 was estimated, the equivalent to 4 protein monolayers. This result does not imply the existence of several adsorbed protein layers.
  
  
  CONCLUSIONS
  It was verified that CBDs were able to penetrate the fibres, according to confocal microscopy and TEM-immunolabelling analysis. The surface concentration of adsorbed CBDs was greater on amorphous fibres (phosphoric acid swollen) than on more crystalline ones (Whatman CF11 and Sigmacell 20).
authors.affiliation: IBB-Institute for Biotechnology and Bioengineering, Centre of Biological Engineering, Universidade do Minho, Campus de Gualtar, 4710-057 Braga, Portugal. joaoricardo@yahoo.com
authors.forename: Ricardo
authors.initials: R
authors.lastname: Pinto
authors.forename: António L
authors.initials: AL
authors.lastname: Amaral
authors.forename: Eugénio C
authors.initials: EC
authors.lastname: Ferreira
authors.forename: Manuel
authors.initials: M
authors.lastname: Mota
authors.forename: Manuel
authors.initials: M
authors.lastname: Vilanova
authors.forename: Katia
authors.initials: K
authors.lastname: Ruel
authors.forename: Miguel
authors.initials: M
authors.lastname: Gama
mesh_terms: D044602:Cellulases / Q000235:genetics / Q000378:metabolism*; D002482:Cellulose / Q000378:metabolism* / Q000648:ultrastructure; D016650:Fluorescein-5-isothiocyanate / Q000378:metabolism*; D005453:Fluorescence; D018613:Microscopy, Confocal; D046529:Microscopy, Electron, Transmission; D011485:Protein Binding; D017434:Protein Structure, Tertiary
chemical_list: D002482:Cellulose; D044602:Cellulases; D016650:Fluorescein-5-isothiocyanate