Determination of fluoride with an ion-selective electrode in the presence of water-soluble organic substances

Abstract

The interference of propylene glycol, ethanol, glycerol and sorbitol in the determination of fluoride by the selective electrode method was investigated. Operational procedures are described which involve both the use of the calibration graph method and the standard additions technique to eliminate possible errors due to the presence of the above water-soluble substances, which are widely used in pharmaceutical products for oral hygiene.