title: Detection and quantification of the selective EP4 receptor antagonist CJ-023423 (grapiprant) in canine plasma by HPLC with spectrofluorimetric detection.
abstract: Grapiprant, a novel pharmacologically active ingredient, acts as a selective EP4 receptor antagonist whose physiological ligand is prostaglandin E2 (PGE2). It is currently under development for use in humans and dogs for the control of pain and inflammation associated with osteoarthritis. The aim of the present study was to develop an easy and sensitive method to quantify grapiprant in canine plasma and to apply the method in a canine patient. Several parameters, both in the extraction and detection method were evaluated. The final mobile phase consisted of ACN:AcONH4 (20 mM) solution, pH 4 (70:30, v/v) at a flow rate of 1 mL/min. The elution of grapiprant and IS (metoclopramide) was carried out in isocratic mode through a Synergi Polar-RP 80A analytical column (150 mm × 4.6 mm). The best excitation and emission wavelengths were 320 and 365 nm, respectively. Grapiprant was extracted from the plasma using CHCl3, which gave a recovery of 88.1 ± 10.22% and a lower limit of quantification (LLOQ) of 10 ng/mL. The method was validated in terms of linearity, limit of detection (LOD), LLOQ, selectivity, accuracy and precision, extraction recovery, stability, and inter-laboratory cross validation, according to international guidelines. The chromatographic runs were specific with no interfering peaks at the retention times of the analyte and IS, as confirmed by HPLC-MS experiments. In conclusion, this was a simple and effective method using HPLC-FL to detect grapiprant in plasma, which may be useful for future pharmacokinetic studies.
authors.affiliation: Department of Veterinary Medicine, University of Sassari, Via Vienna 2, 07100 Sassari, Italy.
authors.forename: Virgina De
authors.initials: V
authors.lastname: Vito
authors.affiliation: Department of Surgical, Medical, Molecular Pathology and Critical Area, University of Pisa, Italy.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Saba
authors.affiliation: School of Veterinary Science, University of Queensland, Gatton Campus, Gatton, QLD 4343, Australia.
authors.forename: Hong-Ki
authors.initials: HK
authors.lastname: Lee
authors.affiliation: College of Veterinary Medicine, Chungnam National University, Daejeon, South Korea.
authors.forename: Helen
authors.initials: H
authors.lastname: Owen
authors.affiliation: Department of Veterinary Pharmacology, Faculty of Veterinary Medicine, University of Kasetsart, Bangkok, Thailand.
authors.forename: Amnart
authors.initials: A
authors.lastname: Poapolathep
authors.affiliation: Department of Veterinary Sciences, University of Pisa, Via Livornese (lato monte), 56122 San Piero a Grado, Pisa, Italy. Electronic address: mario.giorgi@unipi.it.
authors.forename: Mario
authors.initials: M
authors.lastname: Giorgi
mesh_terms: D000818:Animals; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D004285:Dogs; D008297:Male; D058309:Receptors, Prostaglandin E, EP4 Subtype / Q000037:antagonists & inhibitors*; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*; D013449:Sulfonamides / Q000097:blood* / Q000494:pharmacology; D007093:Imidazoles; D011725:Pyridines; D013453:Sulfonylurea Compounds; D000096926:Benzenesulfonamides
chemical_list: D058309:Receptors, Prostaglandin E, EP4 Subtype; D013449:Sulfonamides; C522837:grapiprant; D007093:Imidazoles; D011725:Pyridines; D013453:Sulfonylurea Compounds; D000096926:Benzenesulfonamides
keywords: 423; CJ-023; Dog; Fluorescence; Grapiprant; HPLC