Determination of cyclodextrin content using periodate oxidation by capillary electrophoresis.
A simple and general method suitable for the determination of cyclodextrin content in various matrices is described. The proposed method involves selective cleavage of C-C bonds with vicinal hydroxyl groups by means of periodate (Malaprade's reaction). The amount of produced iodate is monitored by capillary electrophoresis. Optimized electrophoretic conditions (20 mM disodium tetraborate with 1 mM tetradecyltrimethylammonium bromide, direct UV detection lambda = 200 nm) ensure complete separation of periodate and iodate ions and sufficient sensitivity towards iodate. Under optimized reaction conditions (2-fold excess of periodate, temperature 70 degrees C) reproducible quantitative results were obtained for alpha-, beta- and gamma-cyclodextrins as model samples. The proposed method was tested on a real sample of acrylamide--2'-O-allyl-beta-CD copolymer. The values of beta-cyclodextrin content were compared with those obtained by reference NMR measurement and were found to be identical.
Pumera
M
M
Charles University, Department of Analytical Chemistry, Prague, Czech Republic. mpumera@email.cz
Jelínek
I
I
Jindrich
J
J
Coufal
P
P
Horský
J
J
D003505:Cyclodextrins / Q000032:analysis*; D019075:Electrophoresis, Capillary / Q000379:methods*; D009682:Magnetic Resonance Spectroscopy; D010084:Oxidation-Reduction; D010504:Periodic Acid / Q000737:chemistry*; D015203:Reproducibility of Results; D013056:Spectrophotometry, Ultraviolet
D003505:Cyclodextrins; D010504:Periodic Acid; C009288:metaperiodate