Пару лет назад был случай, у молодого человека, выпавшего из окна с 5 этажа, в крови был выявлен клонидин.
Сегодня в инете наткнулся на книгу: Q. Alan Xu, Timothy L. Madden. Analytical methods for therapeutic drug monitoring and toxicology.
Вот в ней, что про клонидин написано:
Цитата
CLONIDINE
CHEMISTRY
Clonidine is an imidazoline antihypertensive. Its chemical name is 2-(2,6-dichloroanilino)-2-imidazoline. Its molecular formula is C9H9Cl2N3, with a molecular weight of 230.1 and a CAS number of 4205-90-7. Clonidine occurs as a white to almost white, crystalline powder. Clonidine is freely soluble in ethanol and methanol. It should be stored in airtight containers.
METHOD
Assay 1 Parekh et al. [1] reported an LC-MS/MS for the determination of clonidine in human plasma. A Shimadzu liquid chromatograph comprising a model LC10AD binary pump, model SIL-HTc autosampler, and model DGU14 degasser was used. The stationary phase was a ThermoHypersil Hypurity C18 column (50 . 4.6 mm, 5 µm particle size). The mobile phase consisted of 2 mM ammonium acetate solution and acetonitrile (20 : 80, vol/vol) and was isocratically delivered at 0.4 mL/min. The injection volume was 10 µL.
A MDS-SCIEX API3000 triple quadrupole mass spectrometer equipped with TurboIonSpray ionization source was operated in the positive-ion mode. The optimized parameters were set as follows: ionspray voltage 1250 V, temperature 350ºC, declustering potential 60 V, collision energy 45 eV, and collision gas nitrogen. Quantification was carried out using multiple-reaction monitoring (MRM) mode at ion transitions m/z 231.9→44.1 for clonidine and m/z 332.1 → 155.1 for nizatidine.
Stock solutions of clonidine and nizatidine at 100 µg/mL were separately prepared in methanol. Working solutions were prepared by diluting stock solutions with a mixture of acetonitrile and water (80 : 20, vol/vol) and stored at 2–8ºC. Nizatidine at 30 ng/mL was used as an internal standard. Standards were prepared by spiking blank human plasma with working solutions. An aliquot of 0.5 mL of plasma sample or standard was mixed with 50 µL of the internal standard solution, vortexed for 10 s, and centrifuged at 15,000 rpm at 10◦C for 5 min. The supernatant was loaded onto an Orochem DVB HL solid-phase extraction cartridge (30 mg/1 mL) that was preconditioned with 1 mL of methanol followed by 1 mL of 2 mM ammonium acetate, drained out, washed with 1 mL of 10% methanol in water, dried, eluted with 1 mL of methanol, evaporated to dryness at 50ºC under a stream of nitrogen, reconstituted with 300 µL of mobile phase, and assayed. Under these conditions, retention times for clonidine and nizatidine were 2.1 and 1.6 min, respectively. There was no interference from endogenous materials in plasma with the analysis of clonidine.
Calibration curves for clonidine were constructed over the range from 50.0 to 2500.0 pg/mL. Correlation coefficients were greater than 0.9983. Intrabatch and interbatch coefficients of variation were less than 14.7 and 15.1%, respectively. Limit of quantification was 50.0 pg/mL.
REFERENCE
1. Parekh SA, Pudage A, Joshi SS, et al., Rapid and sensitive liquid chromatography–tandem mass spectrometry (LC-MS/MS) method for the determination of clonidine in human plasma, J Chromatogr B 867: 172–178 (2008).
Сообщение отредактировал Dodger: 14 Февраль 2011 - 13:59
0
