Evaluation of an HPLC Test for Impurities in the Corticosteroid, 11β,21‐Dihydroxy‐pregna‐1,4‐diene‐3,20‐dione[17a,16a–d]2′‐methyloxazoline‐21‐acetate

Abstract

A high performance liquid chromatographic (HPLC) procedure was developed and evaluated for the determination of impurity levels in bulk 11β,21‐dihydroxy‐pregna‐1,4‐diene‐3,20‐dione[17a,16a–d]2′‐methyloxazoline‐21‐acetate, a corticosteroid compound. A gradient program, with a mobile phase of 0.025 M sodium phosphate buffer in acetonitrile/water (apparent pH 6.9), was used with a Hypersil ODS column. The acetonitrile composition was increased linearly from 15% to 50% over a 40 min period and held at 50% for 10 min. Ultraviolet detection at 245 nm was used to quantify all components. The procedure was validated for accuracy using spiked levels (0.1–1.4% w/w) with three suspected known impurities. A multi‐day repeatability study, using three different Hypersil ODS columns, showed consistent impurity quantification results with one batch lot of the compound.

Keywords:

• Impurity test
• Gradient HPLC
• Steroid
• Drug analysis