An HPLC-DAD validated method for the detection and quantification of cortisol, corticosterone and melatonin in plasma samples of two different animal species

Abstract

The monitoring of endogenous hormone plasma levels could be valuable in biomedical, veterinary and pharmaceutical research. A specific high performance liquid chromatography method with diode array detection, for the assay of cortisol, corticosterone and melatonin in animal plasma was developed and validated. The chromatographic separation was achieved on a C8 reversed phase column with a mobile phase consisting of HPLC-grade water and 35% v/v acetonitrile (pH ± 3.36). The detection was achieved through diode array detection, with two set wavelengths; 245 and 275 nm. The flow rate was at 1 ml/min and the total run time was 50 min. The method was validated according to validation guidelines (Shabir, 2006; US FDA, 2013). The method was found to be linear (R2 > 0.99) over the analytical range (10 to 500 ng/ml) for all three analytes. All the other validation parameters were acceptable and within range. The method was applied to plasma samples from Sprague-Dawley rats and white rhinoceros