Micro and nano polycaprolactone particles preparation by pulsed back-and-forward cross-flow batch membrane emulsification for parenteral administration

In the pharmaceutical field, manufacturing processes which are able to make products with tailored size at suitable shear stress conditions and high productivity are important requirements for their industrial application. Cross-flow and premix membrane emulsification are the membrane-based processes generally used for particles preparation at large scale, however some disadvantages still limit their applicability for the production of fragile products. In this work, we investigated, for the first time, the preparation of micro and nano polymeric particles in a size range between 2.35 (±0.14) ?m and 210 (± 10) nm by using pulsed back-and-forward membrane emulsification for the application in pharmaceutical field. The suitability of the method to produce tailored particles by applying mild shear conditions has been demonstrated. The optimized fluid-dynamic conditions studied allowed the production of particles with target size by selecting the appropriate pore size of the membrane (1 ?m and 0.1 ?m). The uniformity of the particles could be obtained with an axial velocity of 0.5 ms-1 (corresponding to a shear stress of 4.1 Pa) that is 9 times lower than the maximum cross flow velocity reported in literature (4.5 m s-1).