Development and Validation of a Micellar Capillary Electrophoresis Method for Determination of IFNβ-1b in Lyophilized Formulation of a Biosimilar Product

Human interferons (IFNs) are key cytokines secreted by immune system. They have several effects such as antiviral and anti tumors activity, activating immune cells and healing of multiple sclerosis. The type IFNs present in humans are α, β and Υ. IFN β is a polypeptide, normally produced by fibroblasts and seems to be more species-specific than IFN . Structural properties of I FNs are important for their biologic effects. There are a few analytical techniques for separation, identification and determination of IFNs in its formulations such as mass spectroscopy, RP-HPLC and capillary electrophoresis (CE). In this study we used Micellar Electrokinetic Chromatography (MEKC) as a unique mode of CE because of its capability to separate neutral as well as charged solutes. In MEKC, ionic surfactants are added to the running buffer to form micelles which have a three-dimensional structure with the hydrophobic moieties. The selectivity of MEKC can be controlled by the choice of surfactant and also by the addition of modifiers to the buffer. We used sodium tetraborate (Borax) as buffer without any modifier and sodium dodecyl sulfate (SDS) as surfactant. The validated method was used for determination of the IFN β-1b formulation which are manufactured in Iran. From 9 collected different batches, all of them had acceptable potency as claimed on their label with average 102.25 ± 10.030 %. This is the first time that a MEKC method is introduced for quantification of IFN β-1b in its pharmaceutical dosage forms. The method is reliable safe, rapid and accurate.