1. What Are Liposomes and Why Do They Improve Absorption?
Liposomes are microscopicvesicles composed of phospholipid bilayers, mimicking the structure of cell membranes. They act as protective carriers for active ingredients, shielding
them from degradation by stomach acid and digestive enzymes. This allows more
of the active compounds to reach the small intestine intact for absorption.
Moreover, liposomes can fusewith intestinal cell membranes or be endocytosed into cells, facilitating
efficient transport into the bloodstream and enhancing bioavailability.
2. Key Factors Influencing Liposomal Absorption
The efficiency of liposomal delivery depends on several physicochemical properties:
• Particle Size: Smaller vesicles penetrate biological barriers more effectively and are readily taken up by cells.
• Surface Charge & Coating: PEGylation reduces immune clearance and prolongs circulation time.
• Lipid Composition: Tailoring lipid rigidity and composition controls release rate and stability.
• Smart Design: pH-sensitive or enzyme-triggered liposomes enable site-specific release.