Structural characterization of cationic liposomes loaded with sugar-based carboranes

Area of Science:

• Nanomedicine
• Biophysical Chemistry
• Oncology

Background:

• Carboranes are efficient boron delivery agents for boron neutron capture therapy (BNCT).
• Cationic liposomes, utilizing DOTAP and DOPE, are explored as potential vectors for BNCT due to their nuclear targeting capabilities.
• Reducing the high boron concentration required for effective BNCT is a significant challenge.

Purpose of the Study:

• To characterize cationic liposomes loaded with orthocarborane and its sugar derivatives.
• To evaluate the physicochemical properties of these liposomes as potential drug delivery systems for BNCT.
• To understand the insertion modality of carboranes within liposomes.

Main Methods:

• Preparation of cationic liposomes using DOTAP and DOPE.
• Loading liposomes with orthocarborane and its sugar derivatives.
• Physicochemical characterization using Small Angle X-ray Scattering (SAXS) and Small Angle Neutron Scattering (SANS).
• Boron uptake determination via an in situ neutron absorption method.

Main Results:

• Detailed structural properties (shape, size, bilayer composition) of loaded liposomes were established.
• Differences in carborane insertion modalities were observed.
• Insertion differences were correlated with carborane molecular properties and preparation methods.

Conclusions:

• Cationic liposomes show promise as vectors for carborane delivery in BNCT.
• Liposome-carborane interactions are influenced by the carborane's structure and lipophilicity.
• Further research can optimize liposome formulation for enhanced BNCT efficacy.