Quantitative analysis of Celecoxib and carboxyl Celecoxib in human urine by Using HPLC-UV detector: Application to a pharmacokinetic study in Iranian healthy volunteer

Celecoxib (Celebrex) is a cyclooxygenase (COX) inhibitor that exhibits in vitro and in vivo selectivity for COX-2 over COX-1. Celecoxib possesses anti-inflammatory, analgesic and antipyretic activities. The drug has similar efficacy as conventional nonsteroidal anti-inflammatory drugs (NSAIDs) in improving the symptoms of osteoarthritis and rheumatoid arthritis, but it is associated with a lower incidence of gastrointestinal ulceration and complications [1]. This promising gastrointestinal safety profile, together with sustained symptomatic pain relief, places celecoxib as an alternative to the conventional NSAIDs in the treatment of rheumatoid diseases, particularly in patients at high risk of developing gastrointestinal problems. The chemo-preventive effect of celecoxib on colon cancer and its clinical effects on blood platelets renal, hepatic and pancreatic [2]. A simple, selective, and sensitive high performance liquid chromatography (HPLC) procedure has been developed for determination of celecoxib in human urine. Sample preparation involved ultrasound-assisted solvent dispersive liquid-liquid microextraction by chloroform. The HPLC separation was performed on a ZORBAX Eclipse Plus C18 column (100 mm × 4.6 mm, 3.5Micron, Agilent, USA) with a mobile phase of methanol/0.01 % perchloric acid(Gradient: initial 40/60(3min) to final 0/100 at 2 min) at a flow rate of 1.0 mL/min. The peaks were detected by using UV/Vis detector at 255 nm. The extraction recovery was 80.6–90.4% and the method was over the concentration range of 25.0–1000 ng/mL with a lower limit of quantitation (LLOQ) of 32.0 ng/mL using 300 L of urine. The intra- and inter-day accuracy of the method at three concentrations ranged from 97.8% to 105.2% for celecoxib with precision of 5.9–8.7%. This validated method was successfully applied to a pharmacokinetic study enrolling one Iranian volunteers administered a single oral celecoxib extended-release tablet of 200 mg.