Multiple reaction monitoring columns

FIGURE 1.9 Multiple reaction monitored ion chromatograms for desloratadine (top), 3-hydroxydesloratadine (middle), and phosphatidylcholine monoester (bottom) during post-column infusion and subsequent injection of a SPEC(R) MPl-extracted control blank plasma sample.111 (Reproduced with permission from Elsevier.)... 

High-performance liquid chromatography-tandem mass spectrometry method for the determination of gemifloxacin in human plasma was based on the protein precipitation of plasma samples with acetonitrile containing [ C Ha] gemifloxacin as an internal standard. The supernatant was injected onto a PLRP-S column without any further clean-up. The mass spectrometer was operated in positive ion mode, and the ions were detected in multiple reaction-monitoring (MRM) mode. The assay requires 50 gl of plasma and is precise and accurate within the range 10-5000 ng/ml [15]. 

Kim et al. [48] developed a rapid, sensitive, and selective LC-ESI-MS/ MS method for fhe deferminafion of lornoxicam in human plasma. Lornoxicam and isoxicam (infernal standard) were extracted from human phasma wifh efhyl acefafe at acidic pH and analyzed on a Sunfire Cis column with the mobile phase of methanol-ammonium formate (10 mM, pH 3) (70 30). The analyte was detected using a mass spectrometer, equipped with electrospray ion source. The instrument was set in the multiple-reaction-monitoring mode. The standard curve was linear (r = 9998) over the concentration range of 0.5-500 ng/ml. The coefficient of variation and relative error for the intra- and inter-assay at four QC level were 0.7% fo -4.2% and —4.5% to 5%, respectively. The recoveries of... 

A liquid chromatography-tandem mass spectrometry (LC-MS-MS) method was developed to detect tumor-promoting diterpene esters of the tigliane and ingenane types within plant extracts. Fractionation on a Cig HPLC column was followed by MS-MS-multiple reaction monitoring (MRM). 

Fig. 3 Reversed-phase HPLC-MS/MS chromatogram using formic acid in the mobile phase and an Atlantis dC18 column. The standard mixture of alkyl phosphonic acids with a concentration of 10 p,g/ml each was detected using multiple reaction monitoring (MRM) 1) methylphosphonic acid (MPA, miz 96.8 78.7) 2) ethyl methylphosphonic acid (EMPA, mIz 125 96.8) 3) C>-elhyl A,A-dimethylamidophosphoric add (EDMAPA, miz 154.2—>126) 4) isopropyl methylphosphonic acid (iPrMPA, nJz 139.1 %.8) 5) pinacolyl methylphosphonic acid (PinMPA, miz 181.3- 96.8) 6) diisopropyl methylphosphonic add (DiPrMPA, mk 181.3 139.1). See the text for further chromatogr hic details and the MS/MS conditions used.

POCIS extracts and water samples were analyzed for the pharmaceuticals of interest as listed in Table 10.1. Standards and extracts were analyzed on a Quattro Micro triple quadrapole with a Waters 2695 high-pressnre liqnid chromatography (HPLC) and autosampler. Electrospray ionization in positive ion mode was used for detection of target compoimds by multiple reaction monitoring (MRM) with argon collision gas. A Thermo (Bellefonte, PA) Betabasic-18 column (250 x 2.1 mm, 5 p.m, 50°C) was used for separation at a flow rate of 0.2 ml/min with a gradient of methanol... 

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