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Fluoride ion-selective electrode

What are the purposes of using an acetic buffer and sodium chloride in an experiment about determination of fluoride content in sample using ion-selective electrode?

Wallace Chan
- Hong Kong, China
2002

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First of two simultaneous responses --

Tissab is used as a "swamping" agent. If you do not know what that is, I would consult Orien's Electrode manual.They might have it in electronic form on their web site. NaCl-You need to provide more information on the material matrix being tested.

James Watts
- Navarre, Florida
2002

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Second of two simultaneous responses --

I believe the response of the sensing electrode is determined partly by the fluoride concentration and partly by test solution pH (that is, hydrogen ion concentration), so you need a buffer that will result in a substantially constant pH at the testing stage, even though different sample solutions might be different pH as-sampled. Sodium acetate acts as such a buffer.

Bill Reynolds [deceased]
consultant metallurgist - Ballarat, Victoria, Australia
We sadly relate the news that Bill passed away on Jan. 29, 2010.
2002

It is the operation range. If the pH is too low, Hydrogen ion would interfere the detection.The concentration of H do not affect the measurement with pH >5.

Chan Yin
- Hong Kong, China
November 24, 2008

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I am getting interference by chloride while measuring fluoride with solid state F ion selective electrode.
Why is this happening?
None of the literature support this. But I am facing the problem.

Aman Pandey
student - Mumbai, India
December 23, 2008