Biodegradable microparticles preparation by double emulsification—Solvent extraction method: A Systematic study

• Double emulsification—solvent extraction is a robust method for preparing polymeric particles.
• Materials used and process operating conditions were systematically studied.
• Emulsification high shear force governs both small particle size and narrow size distributions.
• Nature of the stabilizing agent determines the electrokinetic behavior of particles.

This work investigates the double emulsification—solvent extraction as method for preparing polycaprolactone biodegradable microparticles. A comprehensive study of this technique is made providing crucial information for designing this kind of carriers. The influence on particle size and zeta potential of different parameters related to the materials used and the process operating conditions were systematically studied. The results provide evidence that the high shear force used for preparing both w1/o emulsion and w1/o/w2 emulsion is a predominant factor for the small particle size and the narrow particle size distributions obtained (particle size around 2 μm; span values lesser than 0.8). The nature of the stabilizing agent plays a comparatively modest role in this respect. On the other hand, the electrokinetic behavior of particles is primarily governed by the nature of the stabilizing agent, and the other investigated variables exert minor effects on the zeta potential. Accordingly, double emulsification solvent extraction can be recognized as a robust method for obtaining narrow microparticles size distribution.

Figure optionsDownload as PowerPoint slide