| Nanoencapsulation of Acetyl Salicylic Acid (ASA) was carried out by a modified double emulsion, using an enteric coating of the copolymers Eudragit L-100 and L -30 D-55 as polymeric matrix. Nanoparticles (NPs) were obtained with different amounts of surfactant (20-40 mg) and stirring rates (12000-15000 rpm) at pH between 1 and 2. The average size of the NPs was around 300 nm. The best results of the nanoencapsulation NPs process were reached with the combination of the copolymer Eudragit L-100 and L-30 D-55, showing nanoparticles yield and encapsulation efficiency higher than 90% and release profiles with smaller burst. The release profiles indicate that the matrix used is suitable to prevent the contact of the active principle with the gastric medium and that this device could achieve a more efficient release in the intestine. |
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