Liposomaal

Liposomaal is a term used to describe liposome-based systems used in medicine and research. Liposomes are small, spherical vesicles formed from phospholipid bilayers that enclose an aqueous core. Their structure allows encapsulation of hydrophilic drugs in the core and incorporation of hydrophobic compounds in the lipid bilayer, making them versatile carriers for a variety of payloads, including drugs, genes, and imaging agents.

Liposomaal formulations vary in size, composition, and surface properties. Common designs use phospholipids with cholesterol to modulate stability, and surface modifications such as polyethylene glycol (PEG) to extend circulation time. Targeting ligands can be attached to improve tissue uptake. Manufacturing methods include thin-film hydration followed by extrusion, ethanol or solvent injection, and newer microfluidic approaches. Loading techniques include passive entrapment during formation and active loading after vesicle formation.

In medicine, liposomaal products are used to improve pharmacokinetics and reduce toxicity. Well-known examples include liposomal doxorubicin for cancer, liposomal amphotericin B for fungal infections, and liposomal irinotecan for pancreatic cancer. Liposome-based vaccines and ocular or dermal formulations also exist. The delivery properties can enable lower peak drug concentrations and reduced off-target effects, but liposomes can face stability challenges, drug leakage, aggregation, and rapid clearance by the reticuloendothelial system. Manufacturing can be complex and costly, and regulatory approval depends on product-specific data.

The field also explores stimuli-responsive and actively targeted liposomes, as well as theranostic approaches that combine therapy with imaging.