Method for derivatization of ephedrine and pseudoephedrine in nonaqueous media and determination by nonaqueous capillary electrophoresis with laser induced fluorescence detection.
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%.
Dong
Yuming
Y
Department of Chemistry, Lanzhou University, Lanzhou 730000, People's Republic of China.
Chen
Yonglei
Y
Chen
Xingguo
X
Hu
Zhide
Z
D019342:Acetic Acid / Q000737:chemistry; D000097:Acetonitriles / Q000737:chemistry; D019075:Electrophoresis, Capillary / Q000379:methods*; D004809:Ephedrine / Q000031:analogs & derivatives* / Q000302:isolation & purification*; D005453:Fluorescence; D007834:Lasers; D015203:Reproducibility of Results
D000097:Acetonitriles; D004809:Ephedrine; D019342:Acetic Acid; C032159:acetonitrile