Simultaneous determination of methylephedrine and pseudoephedrine in human urine by CE with electrochemiluminescence detection and its application to pharmacokinetics

College of Chemistry and Chemical Engineering, Xinyang Normal University, Xinyang 464000, People's Republic of China.
Biomedical Chromatography (Impact Factor: 1.72). 11/2009; 23(11):1138-44. DOI: 10.1002/bmc.1235
Source: PubMed


A novel method for the determination of ephedra alkaloids (methylephedrine and pseudoephedrine) was developed by electrophoresis capillary (CE) separation and electrochemiluminesence detection (ECL). The use of ionic liquid (1-butyl-3-methylimidazolium tetrafluoroborate, BMIMBF(4)) improved the detection sensitivity markedly. The conditions for CE separation, ECL detection and effect of ionic liquid were investigated in detail. The two ephedra alkaloids with very similar structures were well separated and detected under the optimum conditions. The limits of detection (signal-to-noise ratio = 3) in standard solution were 1.8 x 10(-8) mol/L for methylephedrine (ME) and 9.2 x 10(-9) mol/L for pseudoephedrine (PSE). The limits of quantitation (signal-to-noise ratio = 10) in human urine samples were 2.6 x 10(-7) mol/L for ME and 3.6 x 10(-7 )mol/L for PSE. The recoveries of two alkaloids at three different concentration levels in human urine samples were between 81.7 and 105.0%. The proposed method was successfully applied to the determination of ME and PSE in human urine and the monitoring of pharmacokinetics for PSE. The proposed method has potential in therapeutic drug monitoring and clinical analysis.

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    • "According to this plant, compounds such as Protoalkaloids (ephedrine, pseudoephedrine), tannins, saponin, flavones, have always been of great interest among researchers due to their active compounds in pharmaceutical purpose but the most principle activity of Ephedra extractions is in the existence of its alkaloids Eph and Peph (Hoffman et al., 2009; Wang et al., 2009), which may also be prepared by synthesis or transferring Ephedra genomic modification to yeast for biotransformation purpose consider to its relative alkaloids productions (Lue et al., 2009). Ephedra contains about 0.5 -2.0% of alkaloids of the total, ephedrine (and its isomers) forms from 30 to 90% depending on the species (Ganzera et al., 2005; Inoko et al., 2007; Kitani et al., 2009; Liu et al., 2009). Plant cell culture can be established from an impressive array of plant species, including most of those that produce secondary products of commercial interest. "
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    ABSTRACT: An investigation was carried out to determine the relationship between cells biomass, chlorophyll content and production two major alkaloids of Ephedra procera - ephedrine and pseudoephedrine, in callus culture under different ranges of plant growth promote regulators. We find out that kin as a cytokinin is more suitable than BAP for callus and ephedrine and pseudoephedrine productions, subsequently the treatments containing 2 mg l-1 NAA with 1 mg l-1 kin can produce the highest cells biomass with production of 108.1 ± 0.6 μg g-1 dry weight for ephedrine and 730.3 ± 1 μg g-1 dry weight for pseudoephedrine, total chlorophyll content was recorded as 118.4 ± 7.6 μg mg-1 dry weight in this treatment. Considerably in 5th subculture, rhizogenesis occurred in 18% of NAA: 2; kin: 1 treatment and we found out the ephedrine and pseudoephedrine content increased significantly compared with undifferentiated cells in the same hormonal range. This increasing also involved total chlorophyll and chlorophyll b accumulation.
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