Laquaact ph 130

Each varnish formulation sample (0.05 g) was applied at the bottom of a 50 mL transparent plastic polypropylene cup. Twenty-five milliliters of deionized water was then added to the plastic cup and incubated for 30 min at 37 °C. After 30 min, the test solution was moved to another container, and the sample cup was filled with fresh deionized water and incubated again for 30 min. The fluoride ions in the test solution were measured using an ion-selective fluoride electrode (LaquaAct pH 130, HORIBA, Japan) with 25 mL of TISAB solution to strengthen the ion reading. The ion readings were performed three times. The same procedure was repeated to measure the release of fluoride ions for 6 h.

Similar to the fluoride ion release test, 0.05 g of each varnish formulation sample was applied to the bottom of a 50 mL transparent plastic polypropylene cup. Twenty-five milliliters of deionized water was then added to the plastic cup and incubated for 30 min at 37 °C. After 30 min, the test solution was moved to another container, and the sample cup was filled with fresh deionized water and incubated again for 30 min. The calcium ions in the test solution were measured using an ion-selective calcium electrode (LaquaAct pH 130, HORIBA, Japan) with 12.5 mL of ISA solution to strengthen the ion reading. The ion readings were performed three times. The same procedure was repeated to measure the release of calcium ions over 6 h.