HL-3 saline (variable Ca²⁺)

METHOD

• 1. Add all of the dry components to ~750 mL of H₂O. Stir to dissolve.

• 2. Add 5 mL of 1 M KCl solution.

• 3. Add 1 mL of 1 M CaCl₂ solution.

  [Ca²⁺] can be varied from 0.1 to 2 mM if needed. For HL-3 saline solution without Ca²⁺, omit the CaCl₂.

• 4. Adjust the pH to 7.2 with NaOH or HCl.

  Do not use KOH because it will alter [K⁺] in the saline.

• 5. Adjust the final volume to 1000 mL with H₂O.