Journal of Fluorescence

, Volume 19, Issue 4, pp 747–753 | Cite as

An Evaluation of a Fluorometric Method for Determining Binding Parameters of Drug–Carrier Complexes Using Mathematical Models Based on Total Drug Concentration

  • Boontarika Chanvorachote
  • Ubonthip Nimmannit
  • Walaisiri Muangsiri
  • Lee KirschEmail author
Original Paper


A fluorescence method for determining the mode of binding and estimating binding parameters in a model drug-carrier complex was developed using the lipopeptide antibiotic daptomycin and polyamidoamine (PAMAM) dendrimer. Mathematical simulations of model equations describing fluorescence changes induced by antibiotic–carrier binding in terms of total drug concentration were used to evaluate the sensitivity of parameter variation on binding isotherms for both one- and two-site binding models. Nonlinear regression analysis was used to estimate binding parameters and to identify pH-dependent binding models.


Fluorescence methods Drug binding Dissociation constant Capacity constant and Drugcarrier complexes 


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Copyright information

© Springer Science+Business Media, LLC 2009

Authors and Affiliations

  • Boontarika Chanvorachote
    • 1
  • Ubonthip Nimmannit
    • 1
  • Walaisiri Muangsiri
    • 1
  • Lee Kirsch
    • 2
    Email author
  1. 1.Faculty of Pharmaceutical ScienceChulalongkorn UniversityBangkokThailand
  2. 2.Division of Pharmaceutics, College of PharmacyThe University of IowaIowa CityUSA

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