Method for derivatization of ephedrine and pseudoephedrine in nonaqueous media and determination by nonaqueous capillary electrophoresis with laser induced fluorescence detection

✍ Scribed by Yuming Dong; Yonglei Chen; Xingguo Chen; Zhide Hu

• Publisher: John Wiley and Sons
• Year: 2006
• Tongue: English
• Weight: 330 KB
• Volume: 20
• Category: Article
• ISSN: 0269-3879
• DOI: 10.1002/bmc.663

✦ Synopsis

A nonaqueous capillary electrophoresis with laser-induced fluorescence detection method was developed for the quantification of ephedrine and pseudoephedrine after derivatization with 4-chloro-7-nitrobenzo-2-oxa-1, 3-diazol in nonaqueous media. The derivatization was made in off-line mode. By a series of optimizations, a derivatization buffer composed of 40 mm ammonium acetate and 20% acetonitrile and a running buffer composed of 80 mm ammonium acetate and 3% acetic acid were applied for the derivatization and separation of ephedrine and pseudoephedrine, respectively. Linear relationships for ephedrine and pseudoephedrine were obtained in the range 1.23-19.60 mg/L (correlation coefficients 0.9970 for ephedrine and 0.9994 for pseudoephedrine), and the detection limits for ephedrine and pseudoephedrine were 0.014 and 0.011 mg/L, respectively. The method was applied to the analysis of ephedrine and pseudoephedrine in four preparations with recoveries in the range 93.9-105.1%.