LYOPHILIZATION OF SOLID LIPID NANOPARTICLES FOR BRAIN TARGETING
Objective: The aim of this work is to investigate formulation and process parameters that could impact freeze drying of loperamide-loaded Solid Lipid Nanoparticles (Loperamide loaded SLN).
Methods: Loperamide loaded SLN was prepared by high shear homogenization method and freeze dried in vials without and with different types and concentrations of cryoprotectants (lactose, glucose, mannitol and povidon) using pilot freeze dryer.
Results: The best result has been obtained by using 5 % of monosaccharide glucose solution, although Nanoparticles size has been increased 6 folds. However, the total concentration of loperamide hydrochloride (Loperamide HCl) remained unchanged after freeze drying. It has been found that the type and ratio of surfactants adsorbed at the surface of SLN have impact on the success of the drying process.
Conclusion: Results revealed that polymeric nanoparticles could withstand freeze drying stress more than SLN because polymers have higher mechanical resistance in comparison with waxes and lipids.
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