Page 60 - Pharmaceutical Analytical Chemistry II - Pharm D Clinical- 07-PA202
P. 60
Do not store the pH electrode in distilled water.
Potentiometric Determination of Fluoride
We have already known about one type of ion selective electrode
which selectively measures the amount of H3O+ in solution9 pH
meter). There are several other types of ion selective electrodes,
including the one which measures the fluoride ion concentration.
Purpose: To determine the amount of fluoride ion in samples of
toothpaste, mouthwash, and tap water.
- Acetate buffer of pH 5.25 is used to adjust the pH. The potential
of the standard and sample solutions is measured using the
fluoride ion selective electrode.
- The concentration of fluoride is determined using standard
addition or serial dilution (calibration) method.
59