Abstract
A novel liquid chromatographic–electrospray ionization mass spectrometric (LC–ESI-MS) method has been developed for the determination of Armodafinil in human plasma using carbamazepine as internal standard. The sample was prepared by employing liquid–liquid extraction method from human plasma using ethyl acetate as a solvent. The chromatographic separation was achieved within 3.0 min by using 0.2% formic acid: methanol (15:85) as mobile phase on hypurity advance C-18 column (5μ; 100 x 4.6 mm) at a flow rate of 1.0 ml/min. Ion signals m/z “274.1/167.3, 237.0/192.0” for armodafinil and internal standard respectively were measured in the positive ion mode. A detailed validation of the method was performed as per US-FDA guidelines (ICH Q2B). The results of all validation parameters were found to be within the acceptance limits. The drug concentration range from 50-10000 ng/mL was shown to be linear (r2 = 0.9989). Accuracy of the method was found to be >94%, and lower limit of quantification was found at 50 ng/mL. The extraction recoveries were found to be 70.6±0.96% and 67.7±1.32% for ARM and IS, respectively. The recoveries of the stability of sample at different conditions were found to be more than 95%. From the results, it is suggested that the proposed method is simple, reproducible, accurate and precise. So, this method can be applied for the future investigative studies of ARM in human plasma.
Keywords: Armodafinil, Carbamazepine, Human plasma, LC/MS/MS, Liquid-liquid extraction, Method development, Matrix effect, Recovery, Stability, Validation
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