Wound dressing testing: absorbency, retention and MVTR
GelTech Labs measures how wound dressings take up fluid, hold it under load and let vapor out, with methods aligned with EN 13726. Wound-care R&D, product development and quality teams get a full absorbency curve for every sample, run around the clock.
Discuss a pilot studyBetter dressings, chosen sooner, reaching patients faster
A wound heals best when the dressing keeps it moist, not wet, and the market rewards the dressing that proves it can. EN 13726 sets methods, not pass marks, so your data has to defend your specification. A full curve means fewer dead-end constructions and better dressings reaching patients sooner.
- 3x
- higher precision than manual methods, so real differences between constructions stand out.
- A claim backed by a full curve
- Carousel weighs each dressing to 1 mg from first contact to capacity, not once at the end.
- A construction chosen sooner
- Six dressings run side by side, nights and weekends included.
Same 24-hour number, two different dressings
Back a fluid-handling claim with the whole uptake curve through Carousel, so you can show how fast a dressing takes up fluid, not only how much it holds at the end.
Fluid absorbed, % of capacity
Illustrative · mean ± SD
Fluid absorbed, % of capacity. A single 24-hour reading scores these two dressings the same. The curve shows which one takes up a heavy early exudate fast enough.
A single 24-hour reading scores these two dressings the same. The curve shows which one takes up a heavy early exudate fast enough.
Wound dressing tests and what each shows
An MVTR test measures how much water vapor passes through a dressing per unit area over a set time.
| Test | What it shows | Aligned standard |
|---|---|---|
| Free swell absorptive capacity | The most fluid a dressing holds with no load. | EN 13726 |
| Absorption under load | Whether that capacity holds under pressure, as under a bandage. | EN 13726, informative annex |
| MVTR, upright | Vapor loss with only vapor touching the dressing, as over a lightly exuding wound. | EN 13726 |
| MVTR, inverted | Vapor loss with liquid resting on the dressing, as over a wet wound. | EN 13726 |
| Fluid retention | Fluid kept under pressure, so whether exudate squeezes back onto skin. | EN 13726, informative annex |
| Rewet | Fluid a saturated dressing gives back under load, which can wet the wound edge. | Product specification |
| Degradation | Hydrated mass lost in fluid over the wear time. | Product specification |
Test fluid, load and moisture balance
- Test fluid
- Test Solution A, sodium and calcium chloride standing in for exudate.
- Moisture balance
- A wound heals best moist rather than wet: moist wounds epithelialize up to roughly twice as fast as dry wounds (Winter, Nature, 1962).
- Applied load
- Carousel presses 0.1 to 1 PSI, like a compression bandage, at up to 60 °C. Absorption under load runs at 0.3 to 0.7 psi.
Applied loadLike a bandage or body weight
Water vaporLeaves through the backing
Backing filmSets the vapor loss
Absorbent coreHolds fluid
Wound contact layerPasses fluid up
Test fluidStands in for exudate
Dressing classes and what each is judged on
Supplied as fibers, foams, films, sheets, gels or custom formats.
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Alginate
Free swell and wet strength.
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CMC gelling fiber
Retention under pressure.
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Polyurethane foam
Absorption plus MVTR.
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Hydrocolloid
Absorption over the wear time, with a low MVTR.
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Silicone contact layer
Gentle removal and fluid transmission.
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Collagen
Fluid uptake and mass loss.
What this testing doesn't cover
- Clinical or animal studies.
- Sterility or biocompatibility testing.
- The regulatory decision.
How a dressing study starts
Get a dataset and report on your own material through a pilot study: ship us your formulation, or have us formulate it, and our R&D services team runs the study. Teams that test often can run the same methods on their own Carousel, with install, training and a 30-day trial.
- 01
Agree the tests
- 02
Send dressings
- 03
Carousel and integrated instruments run them
- 04
Dataset and report
Plan a pilot dressing study
Send us your dressing and what the study needs to show.