Evaluation of ligand-selector interaction from effective diffusion coefficient.
We present an analytical technique for determination of ligand-selector equilibrium binding constants. The method is based on the measurements of effective molecular diffusion coefficient of the ligand during Poiseuille flow through a long (approximately 25 m), thin (0.254 mm +/- 0.05 mm ID) capillary with and without the selector. The data are analyzed using the Taylor dispersion theory. Bovine Serum Albumin (BSA) and cyclodextrin (CD) were taken as model selectors. We have tested our method on the following selector-ligand complexes: BSA with warfarin, propranolol, noscapine, salicylic acid, and riboflavin, and cyclodextrin with 4-nitrophenol. The results are in good agreement with data from the literature and with our own results obtained within classical chromatography. This method works equally well for uncharged and charged compounds.
Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland. annab@ichf.edu.pl
Anna
A
Bielejewska
Andrzej
A
Bylina
Kazimiera
K
Duszczyk
Marcin
M
Fiałkowski
Robert
R
Hołyst
D000319:Adrenergic beta-Antagonists / Q000737:chemistry; D000818:Animals; D000925:Anticoagulants / Q000737:chemistry; D000996:Antitussive Agents / Q000737:chemistry; D002417:Cattle; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D003505:Cyclodextrins / Q000737:chemistry; D004058:Diffusion; D008024:Ligands; D009596:Nitrophenols / Q000737:chemistry; D009665:Noscapine / Q000737:chemistry; D004364:Pharmaceutical Preparations / Q000737:chemistry*; D017319:Photosensitizing Agents / Q000737:chemistry; D011433:Propranolol / Q000737:chemistry; D012256:Riboflavin / Q000737:chemistry; D020156:Salicylic Acid / Q000737:chemistry; D012710:Serum Albumin, Bovine / Q000737:chemistry; D014859:Warfarin / Q000737:chemistry
D000319:Adrenergic beta-Antagonists; D000925:Anticoagulants; D000996:Antitussive Agents; D003505:Cyclodextrins; D008024:Ligands; D009596:Nitrophenols; D004364:Pharmaceutical Preparations; D017319:Photosensitizing Agents; D012710:Serum Albumin, Bovine; D014859:Warfarin; D009665:Noscapine; D011433:Propranolol; D020156:Salicylic Acid; D012256:Riboflavin; C024836:4-nitrophenol