What is icIEF?

icIEF stands for imaged capillary isoelectric focusing. It's a technique used to separate and characterize proteins based on their isoelectric point (pI). Proteins are separated within a capillary filled with a pH gradient under an electric field. The proteins migrate until they reach the point where their net charge is zero (their pI), at which point they stop migrating and are focused into sharp bands. The separated proteins are then detected using UV absorbance or fluorescence imaging. icIEF is commonly used in biopharmaceutical development for protein characterization, charge variant analysis, and stability studies, especially for monoclonal antibodies and other therapeutic proteins.