Abstract: The present invention describes a method to encapsulate bioactive macromolecules, as example but not limited for, peptidic drugs, into polymeric particles sizing less than 10 ?m of diameter Particle production is based on emulsification/internal gelation procedure and comprises a formation of a water-in-oil emulsion followed by solubilization of dispersed insoluble calcium complex triggering gelation of said polymer dispersed in internal phase, by ionic cross-linking with free calcium ions. Finally, resulting gelled particles dispersed in the oil phase are recovered by partition phases coupled with high speed centrifugation cycles. In this case, the present invention describes a precise methodology to recover said gelled polymeric particles after particle production and includes an addition of acetate buffer solution at predetermined pH, dehydrating agents and residual oil dissolvent agent, at predetermined concentration, followed by high speed centrifugation cycles.