albumin - publications

Predict more albumin - ligand interactions now!

1. J Vac Sci Technol B Microelectron Nanometer Struct Process Meas Phenom. 2011

Probing Albumin Adsorption onto Calcium Phosphates by XPS and ToF-SIMS.

Baio JE, Weidner T, Interlandi G, Mendoza-Barrera C, Canavan HE, Michel R,
Castner DG.

National ESCA and Surface Analysis Center for Biomedical Problems, Department of
Chemical, University of Washington, Seattle, WA 98195.

In this study the binding and assembly of bovine serum albumin (BSA) onto three
different calcium phosphate phases (hydroxyapatite, dibasic calcium phosphate
dihydrate, and β-tricalcium phosphate) was investigated using a combination of
X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass
spectrometry (ToF-SIMS). XPS was used to record adsorption isotherms and to
quantify the amount of BSA adsorbed onto the different CaP surfaces. On all three
surfaces a monolayer of adsorbed BSA was formed. ToF-SIMS was then used to
investigate how the structure of BSA changes upon surface binding. ToF-SIMS data
from BSA films on the three CaP surfaces showed intensity differences of
secondary ions originating from both hydrophobic and hydrophilic amino acids. For
a more quantitative examination of structural changes, we developed a ratio
comparing the sum of intensities of secondary ions from hydrophobic and
hydrophilic residues. A small, but statistically significant, increase in the
value of this ratio (7%) was observed between a BSA film on hydroxyapatite versus
dibasic calcium phosphate dihydrate. From this ratio we can make some initial
hypotheses about what specific changes in BSA structure relate to these
differences observed in the ToF-SIMS data.

PMCID: PMC3260791 [Available on 2012/7/1]
PMID: 22267900 [PubMed]