For fluoride analysis we used ion-selective potentiometry (ion-selective electrode, ISE; pH/ION 735, WTW; measurement performed by Analytische Laboratorien GmbH, Lindlar, Germany).
For fluoride analysis we used ion-selective potentiometry(ion-selective electrode, ISE; pH/ION 735, WTW; measurementperformed by Analytische Laboratorien GmbH, Lindlar, Germany).