ISSN:
1040-0397
Keywords:
Ephedrine
;
N-Nitrosoephedrine
;
Differential pulse polarography
;
Nitrosation
;
Urine
;
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
The nitrosation of ephedrine and the electrochemical reduction of N-nitrosoephedrine were investigated by differential pulse polarography and have been optimized in order to attain the optimum analytical signal. Reduction of the N-nitrosoephedrine was carried out in one irreversible, diffusion-controlled step using potassium chloride-hydrochloric acid. In 0.1 M hydrochloric acid the N-nitrosoephedrine shows a well-defined reduction peak at -0.77 V (vs. Ag/AgCl/ 3 M KCl). An indirect differential-pulse polarographic method is described for the determination of ephedrine at levels higher than 2.5 μg per mL of urine. An extraction procedure with C18 cartridge and a fast and easy nitrosation reaction with sodium nitrite in 0.2 M phthalate potassium hydrogen is also described. Determination of 5 μg/mL of N-nitrosoephedrine in urine samples of 4 mL was possible using the standard addition method, with a relative error of -4.0% and relative standard deviations no higher than 2.1%.
Additional Material:
6 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/elan.1140091518
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