- Five stages: prepare lipid and active, hydrate/mix, reduce size, purify and test, finish as liquid or powder.
- Common methods: thin-film hydration, ethanol injection, high-pressure homogenisation, extrusion.
- Quality is judged by size, PDI, zeta potential, encapsulation efficiency and stability.
- HNOVA™ uses plant-based phosphatidylcholine and a five-step process.
The basic idea
Making a liposome means getting phospholipids to assemble into bilayer vesicles around the active, then shrinking and standardising those vesicles into a narrow size range. The details vary by method, but most processes follow the same five stages.
Starting materials
- Phospholipid — usually phosphatidylcholine (PC). The source (plant or egg), purity and fatty-acid profile all affect vesicle behaviour. HNOVA™ uses plant-based PC.
- The active — water-soluble (added to the aqueous phase) or fat-soluble (dissolved with the lipid).
- Aqueous phase — water or buffer, sometimes with sugars that protect vesicles during drying.
- Optional stabilisers — added where a specific formulation needs them.
Common methods
- Thin-film hydration. Lipid is dissolved in solvent, dried to a thin film and hydrated with water to form multilamellar vesicles, which are then downsized. The classical laboratory method.
- Ethanol (solvent) injection. A lipid–ethanol solution is injected into water, forming vesicles as the solvent disperses. Simple and scalable.
- High-pressure homogenisation / microfluidisation. A coarse dispersion is forced through narrow channels at high pressure, breaking vesicles into a uniform nano-size range. Widely used at production scale.
- Extrusion. Vesicles are pushed through membranes of defined pore size to set the final diameter.
- Sonication. Ultrasound shrinks vesicles; useful at small scale.
Industrial nano-liposome production typically combines a hydration or injection step with high-pressure size reduction, then filtration.
How size and uniformity are controlled
Size is set mainly by the method, the energy applied (pressure, number of passes, pore size) and the lipid composition. The goal is a narrow distribution, measured as the polydispersity index (PDI). Small, uniform vesicles are more stable against aggregation and can be sterile-filtered — see liposome particle size for how these numbers are read.
Purification and drying
After formation, active that was not encapsulated is separated from the vesicles by dialysis, ultrafiltration or size-exclusion chromatography, so encapsulation efficiency can be measured. For powder formats, the liposome dispersion is dried, typically by freeze-drying or spray-drying, with protectants such as sugars so the vesicles re-disperse when water is added.
Quality testing
- Particle size and PDI by dynamic light scattering (DLS).
- Zeta potential — surface charge, an indicator of dispersion stability.
- Encapsulation efficiency — the share of active actually inside the vesicles.
- Morphology — confirmed by electron microscopy (TEM or cryo-TEM) where needed.
- Stability — particle size, leakage and active content over time and temperature.
- Purity and microbial limits — including residual solvents where solvents are used.
See how these are reported per batch on our Quality page.
The HNOVA™ five-step process
HNOVA™ follows a five-step process: plant-based PC selection → precision encapsulation → nano-sized liposome formation (50 to under 200 nm) → enhanced delivery and absorption → maximum results. Formulation, characterisation and manufacturing are all carried out on Hoynoza's Bengaluru campus — see Manufacturing and Science.