Methods
An exosome claim is only as strong as the measurement behind it.
How we choose methods, match them to the source, and report what the data does and doesn’t show.
Methods
No single method answers every question.
Each study pairs methods so one covers what another can’t. This is the panel we draw from.
| Question | Common methods | What it tells you | What it can’t tell you alone |
|---|---|---|---|
| Concentration and size | Nanoparticle tracking analysis, tunable resistive pulse sensing or nano-flow cytometry | How many particles of what size are in the sample | Which of those particles are vesicles |
| Morphology | Transmission electron microscopy or cryo-electron microscopy | Whether intact, membrane-bound vesicles are present | A reliable count across the whole sample |
| Identity | Protein markers chosen for the source, by western blot, ELISA or single-vesicle methods | Whether the particles carry proteins expected for vesicles from that source | Endosomal origin, so whether they are exosomes |
| Purity | Particle-to-protein ratios and markers of what else came along, such as casein or lipoproteins | How much of the preparation is something other than vesicles | Whether the vesicles are active |
| Recovery from your format | Feasibility work on your cream, serum or powder | Whether vesicles can be recovered and measured in the finished product | That every format can be measured; some can’t |
| Stability and consistency | The same panel across lots and storage timepoints | Whether the numbers hold from lot to lot and over shelf life | Performance on skin |
Matched to the source
Each source brings its own lookalikes.
Plant, milk, microbial and human-derived vesicles each get the methods and markers that fit where they came from.
| Source | What else looks like a vesicle | Identity evidence that fits |
|---|---|---|
| Human-derived and cell culture | Protein aggregates and lipoproteins of similar size | Tetraspanin markers such as CD63, CD9 and CD81, alongside a second, independent method |
| Milk and colostrum | Casein micelles of similar size, in large numbers | Casein removed before counting; markers tested with antibodies suited to the species |
| Plant | Debris from broken cells, when tissue is blended, ground or pressed | Plant markers (candidates include TET8 and PEN1), and a clear statement of plant EV or plant-derived nanovesicle |
| Microbial, including microalgae | Cell debris and culture media components | Mammalian markers don’t apply; identity evidence is chosen for the organism |
Independent laboratories
Every measurement runs at an independent laboratory that we name in the study plan, before work starts. You see which lab, which instruments and which methods before you approve the quote.
The Exosome Group sells no ingredients, instruments or manufacturing. We decline work where we would have a stake in the answer. Our founder’s other businesses are named in scope and disclosures.
Exact about words
The word on your label, used correctly.
“Exosome” leads our headlines because it is the word on your label and the word buyers search. Inside our reports, the science stays exact. MISEV2023 recommends “extracellular vesicle” and keeps “exosome” for vesicles whose endosomal origin has been shown, so a report never calls your particles exosomes without that evidence.
exosome
extracellular vesicle
Unless endosomal origin is shown. MISEV2023, Welsh et al. 2024
MISEV2023
MISEV2023 is a map.
MISEV2023 is guidance from the International Society for Extracellular Vesicles on how to produce, separate, characterize and report vesicle studies. It has no pass mark and no certificate, so a product can’t hold a MISEV2023 approval.
We design studies and write reports against each section that applies to your source, and never describe a product as “compliant.”
- How many particles are there?
- What else is in the sample?
- What shows they are vesicles?
- How do they hold up in storage?
On file
What belongs behind a label number.
- The method and instrument that produced it.
- Whether it was measured on the raw ingredient or the finished product.
- How many lots, with lot numbers and dates.
- A blank: the same formula without the vesicle ingredient, measured the same way.
- The unit, written out in full: per mL, per gram or per vial, at release or at expiry.
One lot shows what one sample measured on one day. We treat three lots as the floor behind a label claim. That is how we work, not a regulator’s rule.