Everything Labeled Liposomal
In dietary supplements, liposomal is a marketing word rather than a specification. A genuine liposome is a characterized phospholipid vesicle with measured size, encapsulation efficiency and stability. Most products carrying the term provide none of those numbers.
What a liposome actually is
A liposome is a closed phospholipid bilayer enclosing an aqueous core, produced by a defined process such as thin-film hydration, extrusion or microfluidic mixing. Its identity rests on measurable properties: mean vesicle diameter and polydispersity by dynamic light scattering, encapsulation efficiency after separation of free from encapsulated payload, zeta potential, and lamellarity. Approved injectable liposomal medicines are held to specifications on all of these. A sunflower lecithin dispersion mixed at ambient temperature is usually a coarse emulsion with some mixed micelles, not a vesicle population.
Why the label persists
There is no enforced supplement standard defining the term, so a product can be labeled liposomal without any characterization. The claimed benefit, better absorption, is also rarely tested in the finished product. Where absorption studies exist they are frequently relative comparisons against a poor comparator with no intravenous reference arm, which cannot support an absolute bioavailability figure. In liquid formats, phospholipid oxidation and vesicle fusion during shelf life degrade whatever structure was present at filling.
What to demand from a supplier
Four documents settle it. A dynamic light scattering report with mean size and polydispersity index on the finished product, not on a raw material. An encapsulation efficiency method and result, with the separation technique named. A stability study at the intended storage condition showing size and encapsulation over shelf life. And an oxidation marker such as peroxide value for the phospholipid. If a supplier cannot produce these, the word on the label has no content.
The honest alternative
Say what the formulation is. An emulsion, a solid dispersion, a layered particle or a micellar system each has legitimate uses and describable properties. Describing a format accurately and then proving release and stability is more defensible than borrowing a pharmaceutical term the product does not meet. Vegalab's position is to name the format and publish the numbers: particle size distribution, encapsulation efficiency, release profile and stability at the labeled condition. Those go into a specification a partner can defend on audit, which a borrowed pharmaceutical term cannot.
Key facts
- Approved injectable liposome products are controlled on vesicle size distribution, encapsulation and lipid quality (FDA guidance, Liposome Drug Products, 2018)
- There is no defined or enforced liposomal specification for dietary supplement labeling (21 CFR 101 contains no liposome standard)
- Phospholipid oxidation and hydrolysis are the principal chemical degradation routes for liposomal formulations (Grit and Crommelin 1993, Chem Phys Lipids 64:3)
- Absolute bioavailability claims require an intravenous reference arm (FDA guidance, Bioavailability Studies Submitted in NDAs or INDs: General Considerations, 2022)
How our delivery technology applies
Vegalab does not call its particles liposomal, because they are not vesicle systems. They are multi-layer biopolymer shells, and the claims we support are the ones we can measure: particle size distribution, encapsulation efficiency, release profile and stability under the stated storage condition. A partner can put those numbers in a specification, which a marketing word cannot.
Ask us for the characterization package we supply with every formulation.
Related reading
Last updated: