Voltammetric determination of parthenolide in spiked human plasma and urine.
The voltammetric behaviour of parthenolide, a biologically active sesquiterpene lactone, was studied using direct current (DCt), alternating current and differential-pulse polarography (DPP). Parthenolide developed well-defined cathodic waves over the whole pH range in Britton-Robinson buffers. At pH 10 the diffusion current constant was 3.54 +/- 0.08 (+/- standard deviation; n = 8). The current vs concentration plots were rectilinear over the range 4-36 and 1-28 micrograms/mL in the DCt and DPP modes, respectively, with a minimum detectability of 0.06 microgram/mL (about 1 x 10(-7) M) using the latter technique. The waves were characterised as being diffusion controlled, although adsorption phenomenon played a limited role in the electrode process. The described analytical method was applied to the determination of parthenolide in spiked human urine and plasma; the percentage recoveries were 95.72 +/- 0.22 and 94.0 +/- 0.13 (+/- standard deviation; n = 9), respectively.
Belal
F
F
Department of Pharmaceutical Chemistry, College of Pharmacy, King Saud University, Riyadh 2457, PO Box 11451, Saudi Arabia. almajed99@yahoo.com
Galal
A M
AM
al-Majed
A
A
el-Feraly
F S
FS
D002138:Calibration; D004563:Electrochemistry / Q000379:methods*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D012015:Reference Standards; D012717:Sesquiterpenes / Q000097:blood* / Q000652:urine*
D012717:Sesquiterpenes; C002669:parthenolide