Development of a sensitive and rapid liquid chromatography/tandem mass spectrometry method for the determination of apomorphine in canine plasma

Abstract

A sensitive, rapid and specific quantitative liquid chromatography/tandem mass spectrometry (LC/MS/MS) method was developed and validated for the determination of apomorphine (APO) in canine plasma. The analytes were prepared using one-step liquid-liquid extraction, and analyzed on a Waters Symmetry C(18) column interfaced with triple quadrupole tandem mass spectrometer. A mixture of methanol/0.1% formic acid in water (70: 30, v/v) was employed as the isocratic mobile phase. Positive electrospray ionization was utilized as the ionization source. The analyte and clenbuterol (internal standard) were both detected using multiple reaction monitoring (MRM) mode. The limit of detection (LOD) obtained was 0.03 ng/mL. The assay was linear over the concentration range of 0.1-100 ng/mL, and provided good precision (RSD) and good accuracy (RE). The analyte was stable by using antioxidants throughout the whole study. The experimental results show that LC/MS/MS is a rapid and sensitive method to analyze APO in plasma. Finally, the proposed method was successfully applied to a pharmacokinetic study of APO after intranasal administration of 0.5 mg apomorphine to 10 healthy beagle dogs.

Chromatographic analysis of some drugs employed in erectile dysfunction therapy: Qualitative and quantitative studies using calixarene stationary phase

“…There are a few papers describing the determination of some of these four medicaments simultaneously, most of them reporting determination of a combination of only two pharmaceuticals of these four drugs or even describing the determination of each drug alone at a time . Although the HPLC separations of the pharmaceuticals were extensively studied on calixarene columns over the past decade, to the best of our knowledge there is no work describing the use of calixarene columns for qualitative or quantitative analysis of erectile dysfunction drugs and there is no work dealing with a chromatographic study for the simultaneous analysis of these four drugs.…”

Rapid determination of three anticoagulant rodenticides in whole blood by liquid chromatography coupled with electrospray ionization mass spectrometry

“…Unfortunately, most of the published methods lack sensitivity and selectivity; a false negative or a false positive could have occurred for forensic cases and clinic analyses owing to interference from the complex matrices and low concentrations in the whole blood. Mass spectrometry (MS) has played an important role in toxicology due to its sensitivity, rapidity, and low levels of sample consumption for the characterization and determination; especially in combination with HPLC, it is considered a superior alternative to HPLC/UV or HPLC/FLD for the analyses of many toxic compounds 9–14. Recently, Yang15 reported a method for the determination of bromadiolone using HPLC coupled with electrospray ionization mass spectrometry (ESI‐MS), and obtained a good quantitative result; however, this method had a laborious sample procedure, gradient eluent and determination of only one target compound.…”