Separation and determination of sorbitol and xylitol in multi-component pharmaceutical formulations by capillary isotachophoresis.
Pharmaceutically important polyhydric alcohols sorbitol (SO) and xylitol (XY) are efficiently separated and determined by analytical capillary isotachophoresis (ITP) with conductometric detection. The on-column complex-formation equilibria between the polyols and boric acid are utilized--the terminating borate ion acts as the complexing agent. The ITP operational system used consists of 10 mM HCl + 20 mM imidazole (LE, pH 7.0) and 20 mM boric acid (TE, pH 8.0). The effective mobilities of the borated SO and XY are 8.3 x 10(-9) m2 V-1 s-1 and 7.4 x 10(-9) m2 V-1 s-1, respectively. The ITP analysis is performed with the driving and detection currents of 50 microA (for 700 s) and 20 microA, respectively. The calibration graphs are rectilinear in the range 25-250 mg l-1 of SO and 50 to 500 mg l-1 of XY. The method is applied to the simultaneous assay of SO and XY in three mass-produced multi-component infusion solutions. Favourable values of the method validation parameters obtained confirm the suitability of the proposed ITP method for the quality control of pharmaceuticals.
Pospísilová
M
M
Department of Analytical Chemistry, Faculty of Pharmacy, Charles University, Heyrovského, Czech Republic. pospisim@faf.cuni.cz
Polásek
M
M
Jokl
V
V
D001888:Boric Acids / Q000737:chemistry; D002138:Calibration; D002241:Carbohydrates / Q000032:analysis; D002626:Chemistry, Pharmaceutical; D004586:Electrophoresis / Q000379:methods*; D011108:Polymers / Q000032:analysis; D012996:Solutions; D013012:Sorbitol / Q000032:analysis*; D017186:Titrimetry / Q000379:methods; D014993:Xylitol / Q000032:analysis*
D001888:Boric Acids; D002241:Carbohydrates; D011108:Polymers; D012996:Solutions; C024617:polyol; D013012:Sorbitol; C032688:boric acid; D014993:Xylitol