Formulation of enterosoluble microparticles for an acid labile protein.

Purpose: A microencapsulation method that preserves the activity of an acid labile protein was developed.

Methods: Solvent evaporation technique that employed ICH class 2 and 3 solvents methanol and acetone, respectively to dissolve pH-sensitive Eudragit polymers was investigated. Total protein released and lactase activities were measured using the USP method A for enteric cores and optimized with respect to process parameters.