Determination of binding constants of hydrophobically end-capped poly(ethylene glycol)s with beta-cyclodextrin by affinity capillary electrophoresis.
The formation of inclusion complexes between methoxypoly(ethylene glycol)s (MPEG)s bearing one hydrophobic group (phenyladamantyl) per chain and beta-cyclodextrin (beta-CD) was studied by capillary electrophoresis (CE). The effect of highly sulphated beta-CD (HS-beta-CD) on the migration behaviour of the phenyladamantyl-modified MPEG (MPEG-PhAd) analyte was investigated. It was established that the interaction between the modified PEG and beta-CD involved a 1:1 stoichiometry. Non-linear regression and three usual linearization methods (y-reciprocal, x-reciprocal and double reciprocal) were employed to estimate the binding constants. It was demonstrated that the binding constants were similar (around 400 M(-1)) for two MPEG-PhAd having different chain lengths (2000 and 5000 g/mol).
Karakasyan
Carole
C
Laboratoire de Recherche sur les Polymères, CNRS- Université Paris XII, 2-8 Rue Henri Dunant, 94320 Thiais, France. karakasyan@glvt-cnrs.fr
Taverna
Myriam
M
Millot
Marie-Claude
MC
D019075:Electrophoresis, Capillary / Q000379:methods*; D011092:Polyethylene Glycols / Q000737:chemistry*; D047392:beta-Cyclodextrins / Q000737:chemistry*
D047392:beta-Cyclodextrins; D011092:Polyethylene Glycols; C031215:betadex