Affordable Access

deepdyve-link
Publisher Website

Binding affinity of surface functionalized gold nanoparticles to hydroxyapatite.

Authors
  • Ross, Ryan D
  • Roeder, Ryan K
Type
Published Article
Journal
Journal of Biomedical Materials Research Part A
Publisher
Wiley (John Wiley & Sons)
Publication Date
Oct 01, 2011
Volume
99
Issue
1
Pages
58–66
Identifiers
DOI: 10.1002/jbm.a.33165
PMID: 21793197
Source
Medline
License
Unknown

Abstract

Gold nanoparticles (Au NPs) have been investigated for a number of biomedical applications, including drug and gene delivery vehicles, thermal ablation therapy, diagnostic sensors, and imaging contrast agents. Surface functionalization with molecular groups exhibiting calcium affinity can enable targeted delivery of Au NPs to calcified tissue, including damaged bone tissue. Therefore, the objective of this study was to investigate the binding affinity of functionalized Au NPs for targeted delivery to bone mineral, using hydroxyapatite (HA) crystals as a synthetic analog in vitro. Au NPs were synthesized to a mean particle size of 10-15 nm and surface functionalized with either L-glutamic acid, 2-aminoethylphosphonic acid, or alendronate, which exhibit a primary amine for binding gold opposite carboxylate, phosphonate, or bisphosphonate groups, respectively, for targeting calcium. Bisphosphonate functionalized Au NPs exhibited the most rapid binding kinetics and greatest binding affinity to HA, followed by glutamic acid and phosphonic acid. All functional groups reached complete binding after 24 h. Equilibrium binding constants in de-ionized water, determined by nonlinear regression of Langmuir isotherms, were 3.40, 0.69, and 0.25 mg/L for bisphosphonate, carboxylate, and phosphonate functionalized Au NPs, respectively. Functionalized Au NPs exhibited lower overall binding in fetal bovine serum compared to de-ionized water, but relative differences between functional groups were similar.

Report this publication

Statistics

Seen <100 times