PhD Scientific Days 2022

Pharmaceutical Sciences I.

Development of liposomal corticosteroids

Text of the abstract

Introduction: Corticosteroid-loaded liposomes are nano-scale drug-delivery systems. This
approach has several benefits in the anti-inflammatory therapy in terms of biopharmaceutical
parameters like adsorption, biodistribution and controlled release of the drug.
Aims: Our goals were the following: 1) to reveal the effect of the incorporated steroid
molecules on the phase-transition temperature (T c ) of liposomes; 2) to find the best
composition of phospholipids keeping the T c of liposomes in the range of inflamed tissue
temperature; 3) to visualize the liposomes.
Method: Three different kinds of lipids: dipalmitoyl-phosphatidylcholine (DPPC), distearoyl-
phosphatidylcholine (DSPC), and dimyristoyl-phosphatidylcholine (DMPC) were used in 2
combinations to prepare prednisolone-loaded liposomes. Small unilamellar liposomes were
gained by thin layer hydration followed by extrusion. The particle size-distribution was
measured by dynamic light scattering (DLS) for 1 year. Differential scanning calorimetry
(DSC) was used to determine the exact T c values. The liposomes were visualized by atomic
force microscopy (AFM).
Results: The drug-loaded liposomes showed narrow particle size distribution around 100 nm
of hydrodynamic diameter througout the 1-year long observation period for each composition.
The DSC results revealed 40-41 °C of T c for drug-free liposomes and no significant influence
of prednisolone. The AFM pictures proved the predicted-size of liposomes.
Conclusions: We could successfully create prednisolone-loaded liposomes with 100 nm in
diameter, which were stable at least for 1 year at 25°C. The calculated and measured T c values
are almost the same with or without added drug.
Funding: Semmelweis 250+ Excellence PhD Scholarship, EFOP-3.6.3-VEKOP-16-2017-
00009, NKFI FK 124147, TKP2021-EGA-23