title: Determination of piroxicam from rat articular tissue and plasma based on LC-MS/MS.
abstract: Osteoarthritis (OA) is the most common type of arthritis. To manage OA, in general, oral administration of non-steroidal anti-inflammatory drugs (NSAIDs) is used. Recently, the analgesic and anti-inflammatory efficacy of piroxicam (PX), a long-acting NSAID, by intra-articular (IA) administration in OA was reported, and the possibility that PX is distributed in articular tissues at a certain concentration was raised. Thus, herein, novel LC-MS/MS methods to detect PX in rat articular tissue and plasma are presented. For articular tissue, solvent extraction with acetonitrile for 12 h was employed and a protein precipitation method was used for the preparation of a plasma sample. The developed methods were validated by following the FDA guidelines, and the validated methods were successfully applied to a PK study of IA PX. The present study presents, to our knowledge, the first method of determining a drug in articular tissue. Additionally, the level of PX in articular tissue after IA PX administration was experimentally confirmed for the first time using the present methods. Therefore, the present methods provide a new direction for in vivo evaluation for IA PX formulations and contribute to the development of alternative IA PX formulations with better effects for the treatment of OA.
authors.affiliation: College of Pharmacy, Dankook University, Cheonan, Chungnam, 31116, South Korea.
authors.forename: Han Sol
authors.initials: HS
authors.lastname: Kim
authors.affiliation: College of Pharmacy, Dankook University, Cheonan, Chungnam, 31116, South Korea.
authors.forename: Ha Ra
authors.initials: HR
authors.lastname: Cho
authors.affiliation: College of Pharmacy, Dankook University, Cheonan, Chungnam, 31116, South Korea.
authors.forename: Myoung Jin
authors.initials: MJ
authors.lastname: Ho
authors.affiliation: College of Pharmacy, Dankook University, Cheonan, Chungnam, 31116, South Korea.
authors.forename: Myung Joo
authors.initials: MJ
authors.lastname: Kang
authors.affiliation: College of Pharmacy, Dankook University, Cheonan, Chungnam, 31116, South Korea. analysc@dankook.ac.kr.
authors.forename: Yong Seok
authors.initials: YS
authors.lastname: Choi
mesh_terms: D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000008:administration & dosage / Q000032:analysis* / Q000097:blood; D002358:Cartilage, Articular / Q000187:drug effects / Q000378:metabolism*; D002853:Chromatography, Liquid / Q000379:methods; D007270:Injections, Intra-Articular; D010894:Piroxicam / Q000008:administration & dosage / Q000032:analysis* / Q000097:blood; D051381:Rats; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D010894:Piroxicam
keywords: Articular tissue; Intra-articular administration; LC–MS/MS; Osteoarthritis; Piroxicam; Plasma