Recommendation For Fluids - Fluigent FLOW UNIT User Manual

Recommendations for fluids
Working with multiple liquids
Switching between multiple liquids can leave transient deposits in
the form of liquid layers inside the glass capillary. This is especially
common for insoluble liquids, but can happen even with miscible
liquid combinations. For example, when IPA is followed by water in a
sensor without drying in between, large offsets can be observed for
hours after switching to water.
If possible, dedicate a separate sensor for each different liquid to be
measured. If not possible, use caution when switching media and
clean properly.
Working with water
When working with water it is recommended not to let the sensor dry
out. All salts and minerals in the water will deposit on the glass and
are difficult to remove. Although salt solutions are particularly prone
to problems, even clean water can still contain enough dissolved
minerals to form a deposition layer. Flush with DI water on a regular
basis to prevent build-up. If you still encounter problems, occasionally
flush the sensor with slightly acidic cleaning agents.
When working with water containing organic materials (sugars, etc.)
microorganisms often grow on the walls of the glass capillary and
form an organic film that can be difficult to remove. Flush on a regular
basis with solvents such as ethanol, methanol or IPA, or with cleaning
detergents to remove organic films.
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CLEANING PROCEDURE CLEANING PROCEDURE
Working with silicone oils
When working with silicone oil it is recommended not to let the sensor
dry out. Silicone oils can be cleaned out using special cleaners. Check
with your silicone oil supplier for cleaning agents compatible with
glass surfaces.
Working with paints or glues
When working with paints or glues it is critical not to let the sensor
dry out. Often, depositions of paints and glues cannot be removed
anymore after they have dried. Flush the sensor with cleaning agents
recommended by your paint or glue manufacturer that are compatible
with glass. Ensure that you have found a good cleaning procedure
before performing the first tests, and always clean shortly after emptying
the sensor.
Working with alcohols or solvents
Unlike most other fluids, alcohols and solvents are not critical and a
short flush of isopropanol (IPA) is sufficient to clean the capillary walls.
Other liquids or applications
If uncertain about your application and how to clean the flow sensor,
please contact FLUIGENT for additional support at support@fluigent.
com.
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