کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1224259 967916 2007 6 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Study on complex formation of biologically active pyridine derivatives with cyclodextrins by capillary electrophoresis
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی آنالیزی یا شیمی تجزیه
پیش نمایش صفحه اول مقاله
Study on complex formation of biologically active pyridine derivatives with cyclodextrins by capillary electrophoresis
چکیده انگلیسی

The capillary electrophoretic separation of the pyridine derivatives pyridoxine, pyridoxal, nicotinamide, nicotinic acid and isonicotinic acid in phosphate buffer using cyclodextrins as buffer additives was studied at pH 2.0 and 3.5. Superior separation was achieved at pH 2.0. Addition of α- and β-cyclodextrin and the respective 2-hydroxypropyl derivatives as well as carboxymethyl-α-cyclodextrin to the running buffer did not significantly improve the resolution of the compounds. The interactions of α- and β-cyclodextrin as well as their hydroxypropyl derivatives with the pyridine derivatives were investigated by capillary electrophoresis at pH 2.0. No complex formation was observed between the cyclodextrins and pyridoxine, pyridoxal and nicotinamide. α-Cyclodextrin and 2-hydroxypropyl-α-cyclodextrin form weak 1:1 complexes with nicotinic and isonicotinic acids in aqueous media at 298.15 K, while β-cyclodextrin and its hydroxypropyl derivative did not form complexes. The apparent stability constants (K) of the complexes calculated from the electrophoretic mobility data ranged between 3 and 33 kg/mol. The negative values of enthalpy and entropy of complex formation obtained from the graphical plot of the van’t Hoff equation indicate an important role of van der Waals and electrostatic interactions in the binding of nicotinic acid with α-cyclodextrin.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Pharmaceutical and Biomedical Analysis - Volume 45, Issue 4, 30 November 2007, Pages 688–693
نویسندگان
, ,