High-Performance Liquid Chromatography Determination of Meloxicam and Piroxicam with Ultraviolet Detection

A simple accurate and sensitive high-performance liquid chromatographic method for the determination of meloxicam and piroxicam concentrations in small volume plasma samples has been developed. Following a liquid extraction using chloroform, samples were separated by reversed-phase high-performance liquid chromatography on an XBridge C18 column (4.6 × 250 mm) and quantified using ultraviolet detection at 360 nm. The mobile phase was a mixture of water with glacial acetic acid (pH 3.0) and acetonitrile (50 : 50), with a flow rate of 1.0 mL/min. The standard curve ranged from 5 to 10,000 ng/mL for meloxicam in bearded dragon (Pogona vitticeps) plasma and piroxicam in crane (Grus rubicunda) plasma. Intra- and interassay variability for meloxicam and piroxicam were less than 10% and the average recovery was greater than 90% for both drugs. This method was developed in bearded dragon and crane plasma and should be applicable to any species, making it useful for those investigators dealing with small sample volumes, particularly when conducting pharmacokinetics studies which require multiple sampling from the same animal