Liquid chromatography tandem mass spectrometry with triple stage fragmentation for highly selective analysis and pharmacokinetics of alarelin in rat plasma

Abstract

Alarelin, a gonadotropin‐releasing hormone analogue, is widely used in China for the treatment of endometriosis and uterine leiomyoma. In order to investigate its pharmacokinetic behavior and support the preclinical application of new formulations, we have developed a novel and highly selective bioanalytical method to determine alarelin in rat plasma based on liquid chromatography tandem mass spectrometry with triple stage fragmentation. After sample preparation by protein precipitation followed by reversed phase solid phase extraction, alarelin and triptorelin (internal standard) were chromatographed on an Ascentis® Express C18 column (50 mm × 4.6 mm, 2.7 µm) using gradient elution with 0.1% formic acid in water and acetonitrile at a flow rate of 1 mL/min. Detection was by positive mode electrospray ionization followed by triple stage fragmentation using the transitions at m/z 584.6→249.1→221.0 for alarelin and 656.5→249.1→176.0 for triptorelin, The assay was linear in the concentration range 0.3‐10 ng/mL with excellent precision and accuracy. It was successfully applied to a pharmacokinetic study in rats administered a dose of 13.5 µg/kg alarelin by intramuscular injection. The results show that the triple stage fragmentation strategy allows highly selective analysis of alarelin and has the potential to be widely applied to the bioassay of other peptidic drugs.

Recent advances in the bioanalytical methods of polyethylene glycols and PEGylated pharmaceuticals

“…MRM assay is a target MS technique based on ESI–MS [182–191]. The operating principle composes following stages: in the first quadrupole (Q1), an analyte ion with certain mass will be selected; the selected ions will be consequently fragmentized by collision‐induced dissociation (CID); a single or multiple specific fragment ions are selected again by the second quadrupole (Q2) and transmitted into the third quadrupole (Q3) for detection (Figure 5I) [192–197].…”

Capillary Electrophoresis–Mass Spectrometry with Multisegment Injection and In-Capillary Preconcentration for High-Throughput and Sensitive Determination of Therapeutic Decapeptide Triptorelin in Pharmaceutical and Biological Matrices

“…The LC strategies are considered as a gold standard for pharmaceutical and biomedical analyses. Although LC represents a dominating technique also for quantitative analysis of peptides and peptide or protein-based drugs [7][8][9][10], capillary electrophoresis (CE) is traditionally a powerful alternative to LC in analysis of biomolecules. This is due to several inherent benefits of CE including enhanced selectivity for charged substances, high speed of analysis, high separation efficiency and low consumption of the sample.…”

Development and validation of a liquid chromatography‐tandem mass spectrometry method with triple‐stage fragmentation to determine levetiracetam in epileptic patient serum and its application in therapeutic drug monitoring

“…Subsequently, the product ions generated in Q2 are enriched and then captured in Q3 (linear ion trap). Finally, the selected product ions are further fragmented Q3 (linear ion trap) and the second‐generation fragment ions are scanned out to the detector [24–26]. To the best of our knowledge, this is the first study to use the LC‐MS 3 technique for the determination of LEV in human serum.…”