Analytical Contract Lab Providing Particle Size and Characterization Testing Services

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Dynamic Vapor Sorption - DVS

Dynamic vapor sorption (DVS) Diagram

Moisture sorption properties of a material can provide critical information on the stability, processing, performance, and storage of materials. Moisture sorption analysis is applicable to pharmaceuticals, food products, packaging, personal care products, fibers, building materials and agricultural materials.

Dynamic vapor sorption (DVS) is a gravimetric technique that measures the quantity, and how quickly water vapor is adsorbed and/or absorbed by a material, such as cement, or an active pharmaceutical ingredient. Accurate measurements are achieved by controlling the temperature and humidity electronically, allowing excellent instrument baseline stability as well as accurate control of the generated relative humidity.

DVS instruments work by flowing precisely controlled concentrations of water vapors in dry air over a sample at a known flow rate and temperature. The sample rests on a digital microbalance which detects the sorption/desorption of water vapor through the increase or decrease in mass of the material as the relative humidity (RH) varies. DVS instruments can also perform isoactivity (or isohume) measurements in which materials are kept under constant RH conditions while linearly or stepwise varying the temperature.

Additionally, DVS instruments can be set up to assess permeability of water vapor through a thin barrier, e.g. packaging materials or membranes. The sample pan is filled with a known desiccant (e.g. molecular sieves), sealed with the membrane of interest, and exposed to high RH levels. Alternately, the sample pan is filled with water or saturated salt solutions with known water activity, sealed with the membrane of interest, and exposed to low RH levels.

DVS instruments provide a relatively quick way of obtaining the water sorption and desorption isotherm of the sample (typically in 3-5 days) compared to traditional methods (typically weeks to months).

Two instrument models are available at PTL with the following specifications:


SMS DVS Intrinsic 1

ProUmid Vsorp Plus

Recommended sample quantity

50-100 mg

1-100 g

Sample pan size

8 mm base diameter,

3 mm depth

50 mm base diameter,

11 mm depth

Balance resolution

± 0.1 µg

± 10 µg (up to 111 g)

or ± 100 µg (up to 220 g)

Temperature range

20 – 40 °C

15 – 40 °C

Humidity range

0 – 98% RH

Max RH depends on analysis temperature,

e.g. 0 – 95% RH at 25 °C,

0 – ~70% RH at 15 or 40 °C


1 sample at a time

Up to 11 samples at a time

Permeability analysis

Not available at PTL

Available at PTL

Qualified for cGMP use?


Not at this time



DVS Applications

  • Studying hygroscopicity of powders, fibers and solids
  • Kinetics of water sorption and desorption
  • Water induced morphology changes
  • Food shelf-life prediction studies
  • Effects of moisture on texture of materials
  • Accelerated stability studies of active pharmaceutical ingredients (APIs)

Materials Studied

  • Pharmaceuticals: powders, tablets, APIs and excipient materials
  • Food: powders, processed food, biscuits
  • Natural Materials: grains/seeds, wood 
  • Building Materials: aggregates, cement, ceramics
  • Personal Care Products: cosmetics, hair care, contact lenses
  • Packaging Materials: paper, plastics


Ready to get started?

Click the button to the right to learn how to submit sample material for particle size and characterization analyses. If you have more questions along the way, please contact us.