Raditya Weka Nugraheni
1, Dwi Setyawan
1, Helmy Yusuf
1*1 Department of Pharmaceutics, Faculty of Pharmacy, Universitas Airlangga. Surabaya, Indonesia
Abstract
Background: The present study aims to
design formulation of liposomes that are well-preserved during freeze-drying.
The combination of Hydroxy Propyl Methyl Cellulose (HPMC) as dispersion matrix
and lyoprotectants; maltodextrin or mannitol, was
employed to prevent aggregation and/or recrystallization. The obtained
dry products were investigated in terms of their physical characteristics.
Methods: Liposomes were prepared using
thin film method and hydrated with the lyoprotectant solution. The formed
liposomes were mixed with HPMC gel and freeze-dried. The obtained solid
products were characterized using Differential Scanning Calorimetry (DSC),
X-Ray Diffraction (XRD), and Scanning Electron Microscopy (SEM).
Results: The DSC thermograms of
formulations with maltodextrin were relatively homogenous, yet exhibiting
meta-stable properties. In contrast, the formulations using mannitol showed
phase separation. These results were confirmed by XRD data, in which
formulations with maltodextrin showed no intensive peaks, indicating amorphous
solid while the formulations with mannitol exhibited more intensive peaks,
indicating the presence of crystalline solids. The SEM images of both
maltodextrin and mannitol-containing formulations showed porous matrix with
spherical liposomes trapped in the matrices. The SEM images also correspond to
the DSC and XRD data, where crystalline solid existed in the
mannitol-containing formula.
Conclusion: The
developed liposomes
formulation using combination of HPMC matrix and maltodextrin showed potential
in preserving liposomes structure, contrary to those of using mannitol.