It is applied mainly with fluoride ion-selective electrodes (ISE) for accurate potentiometric analysis of samples like water tea or soil by adding at a 11 ratio to standards and unknowns.

Its primary purpose is to fix ionic strength for linear calibration buffer pH to free fluoride ions and chelate interfering metal ions (e.g. Al Fe) via CDTA ensuring activity-based measurements rather than concentration-dependent ones.

Total Ionic Strength Adjustment Buffer (TISAB) solution is a colorless aqueous mixture primarily containing CDTA (or EDTA in some variants) sodium chloride acetic acid and sodium hydroxide designed to maintain stable pH around 5-6.