Vobis - Liposomes for Drug Delivery
Liposomal encapsulation experience particularly specific to lipid-based nanoparticles with encapsulation of variety of payloads including small molecules and nucleic acids (plasmid DNA, siRNA and ASO). We have developed proprietary lipid based nano technologies that have potential benefits in different therapeutic areas including targeted cancer therapy, DNA Vaccination and liver diseases. Here are the some of the highlights related to our LNP and liposomal experience including type of liposomes and techniques.
Types of Liposomes
Conventional liposomes: The lipid layer of liposomes is negatively and positively charged phospholipids and cholesterol, which are attached to aqueous core. The bilayer of lipid and the aqueous penetrate through the hydrophobic and hydrophilic compounds, respectively.
pH-sensitive liposomes: The lipid composition of liposomes, destabilize when the external pH changes from a neutral or alkaline to an acidic state.
Cationic liposomes: The liposome contains one positive (cationic) charged (phospho)lipid. It interacts with negatively charged compounds or nucleic acids at the time of a simple mixing process.
Immuno liposomes: The liposomes contain antibody molecules or substances in the liposomal surface.
Long circulating liposomes: The hydrophilic layer of oligosaccharides, glycoproteins, polysaccharides and synthetic polymers are coated to the liposome surface, which helps to allow the prolonged circulation of the liposomal material in drug delivery systems.
Techniques involved in liposome microencapsulation
Passive loading techniques
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Mechanical dispersion method
Lipid film hydration
Micro emulsification
Membrane extrusion -
Solvent dispersion method
Ethanol or ether injection
Double emulsion
Reverse phase evaporation vesicles -
Detergent removal technique
Dialysis
Gel permeation chromatography
Diffusion
Active loading techniques
- Citrate method
- Ammonium sulfate method
- Ionophore generated pH gradient method