Transfer exactly 25 ml of the same amino acid solution into a clean, 50 ml conical flask.

Insert the rinsed electrode of the calibrated pH meter into the solution. Record the initial pH.

Obtain 20 ml of 1 M NaOH. Slowly add 0.2 mL NaOH and mix the solution by swirling. Wait for the pH value to stabilize on the pH meter and record the pH.

Again, add 0.2 ml NaOH swirling and record the pH.

Continue the titration until the solution reaches a pH of 12.0 ± 0.1