Determination of formoterol in rat plasma by liquid chromatography-electrospray ionisation mass spectrometry.
A sensitive method for the determination of formoterol in rat plasma is described, using high performance liquid chromatographic separation with tandem mass spectrometry. Samples were purified using liquid-liquid extraction and separated on CAPCELL PAK C18 UG120 (2.0 x 150 mm) with a mobile phase consisting of a mixture of methanol- 50 mM ammonium hydrogen carbonate (1:1 v/v). Detection was performed with a TSQ 7000 mass spectrometer using positive ion electrospray ionisation, monitoring the shift from precursor ions for formoterol at m/z 344.9 to product ions of m/z 121.0. The limit of quantitation of the method was found to be 0.1 ng/ml, when using 0.1 ml plasma. Plasma concentrations of formoterol could be quantified from 0.15 to 7.01 ng/ml, allowing the analysis of samples up to 32 h after a single oral dose of formoterol fumarate (0.25 mg) to rats.
Kakubari
I
I
Research Department, Saitama Daiichi Pharmaceutical Co., Ltd., Kasukabe, Saitama, Japan. kakubari@sdsk.co.jp
Dejima
H
H
Miura
K
K
Koga
Y
Y
Mizu
H
H
Takayasu
T
T
Yamauchi
H
H
Takayama
S
S
Takayama
K
K
D000318:Adrenergic beta-Agonists / Q000097:blood*; D000818:Animals; D002851:Chromatography, High Pressure Liquid; D004983:Ethanolamines / Q000097:blood*; D000068759:Formoterol Fumarate; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D012015:Reference Standards; D015203:Reproducibility of Results; D012996:Solutions; D021241:Spectrometry, Mass, Electrospray Ionization
D000318:Adrenergic beta-Agonists; D004983:Ethanolamines; D012996:Solutions; D000068759:Formoterol Fumarate