Identification and Structural Elucidation of New Process Impurity in Testosterone.

The main objective of this study is identification, isolation and characterization of potential impurity of testosterone. Testosterone was analyzed as per European pharmacopeial method for related substances by high-performance liquid chromatography (HPLC). One new unknown impurity was found along with other pharmacopeial impurities at a level more than 0.10%. This unknown impurity was isolated by preparative HPLC using Symmetry C18 column. The isolated impurity was spiked in sample containing impurities and was found to have the same retention time as that of this unknown impurity. This isolated impurity was fully characterized by different spectroscopic techniques such as LC-MS/MS, 1H, 13C NMR and DEPT as per the requirements of the ICH guidelines and was characterized as bisnoralcohol impurity.