Dispersion of Colloidal Suspensions and Their Stability

Lyophilization and nebulization of pulmonary surfactant-coated nanogels for siRNA inhalation therapy

“…Following reconstitution of the lyophilized cake (LYO CS-siNGs), no significant differences were obtained in NP size and surface charge compared to ex novo prepared particles, with all tested formulations having a hydrodynamic diameter < 200 nm, a zeta-potential < -20 mV and a PDI < 0.3. Hence, the CScoated siNGs can be lyophilized, preserved as a dry powder and easily reconstituted whilst maintaining colloidal stability [44,45]. Interestingly, although lyo-or cryoprotectants such as trehalose are often required to prevent aggregation of lipid-based NPs after reconstitution [26,28], colloidal stability of CS-coated siNGs was maintained without addition of stabilizing excipients.…”