Analytical control of a pharmaceutical formulation of sodium picosulfate by capillary zone electrophoresis.
A new procedure for the analytical control of a pharmaceutical formulation by capillary zone electrophoresis (CZE) is proposed. It allows the simultaneous determination of the major compounds in the formulation: active compound (sodium picosulfate) and preservative (methylparaben), and the degradation products of the preservative, which slowly degrades by hydrolysis or by transesterification with sorbitol (sweetener in excess in the formulation) yielding p-hydroxybenzoic acid and sorbitolparaben, respectively. UV-Vis detection in the absorption maxima of the analytes and 20 mM borate solution at pH 10 as background electrolyte are used. Results are compared with those provided by the HPLC procedure. The method has also been validated using the HPLC procedure as the reference method, evaluating selectivity, accuracy, linearity and precision. The CZE procedure developed is sufficiently accurate and the precision achieved is about 1% for major and 3% for minor compounds.
Departament de Química, Facultat de Ciències, Universitat Autònoma de Barcelona, Bellaterra, Spain. iqan8@blues.uab.es
M
M
Blanco
J
J
Coello
H
H
Iturriaga
S
S
Maspoch
M A
MA
Romero
D002138:Calibration; D002851:Chromatography, High Pressure Liquid; D002951:Citrates; D019075:Electrophoresis, Capillary / Q000379:methods*; D009942:Organometallic Compounds; D010226:Parabens / Q000032:analysis; D004364:Pharmaceutical Preparations / Q000737:chemistry*; D010847:Picolines / Q000032:analysis*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013012:Sorbitol / Q000032:analysis
D002951:Citrates; D009942:Organometallic Compounds; D010226:Parabens; D004364:Pharmaceutical Preparations; D010847:Picolines; D013012:Sorbitol; C015358:methylparaben; C005701:picosulfate sodium