Instructions for preparation of powdered medium

All powdered cell culture media are with L-Glutamine and without sodium bicarbonate.

Procedure:

  • To a mixing container that is as close to the final volume as possible, add 10% less distilled water than the desired total volume of medium.
  • Add powdered medium to room temperature water with gentle stirring. Do not heat water.
  • Rinse inside of package to remove all trace of powder.
  • Add Sodium Bicarbonate as required.
  • Dilute the medium to the desired volume with distilled water and stir until dissolved. Do not overmix.
  • Adjust the pH to between 0.2 – 0.3 below the desired final working pH by slowly adding, with stirring, 1NaOH/ 1N HCI. The pH usually will rise 0.2 – 0.3 units upon filtration. Keep the container closed until the medium is filtered.
  • Process the medium immediately into sterile containers by membrane filtration using 0.2 micron filter.

Example I

DMEM (11-055-1) – 1 liter

  • Prepare 900ml of distilled water in clean glass beaker. Water temperature should be 15-30ºC. Put the beaker on a stirrer and add a magnet.
  • Add the 1-liter powder to the water and stir gently. Fill some distilled water into the empty package, stir and pour the remains into the beaker. Stir till completely dissolved.
  • Add 3.7 gram Sodium Bicarbonate (or 49.4 ml of 7.5% Sodium Bicarbonate Solution).
  • Adjust pH to 0.2-0.3 units below the required pH using 1N HCl or 1N NaOH. The pH will rise by 0.1-0.3 units after filtration.
  • Add distilled water up to 1 liter.
  • Filter for sterility with 0.2µ filter into sterile bottles.
  • For the preparation of 10 liters multiply by 10.

Example II

RPMI 1640 (11-100-1) – 1 liter

  • Prepare 900ml of distilled water in clean glass beaker. Water temperature should be 15-30ºC. Put the beaker on a stirrer and add a magnet.
  • Add the 1-liter powder to the water and stir gently. Fill some distilled water into the empty package, stir and pour the remains into the beaker. Stir till completely dissolved.
  • Add 2 gram Sodium Bicarbonate (or 26.67 ml of 7.5% Sodium Bicarbonate Solution).
  • Adjust pH to 0.2-0.3 units below the required pH using 1N HCl or 1N NaOH. The pH will rise by 0.1-0.3 units after filtration.
  • Add distilled water up to 1 liter.
  • Filter for sterility with 0.2µ filter into sterile bottles.
  • For the preparation of 10 liters multiply by 10.

Sodium Bicarbonate Concentrations:

Cat. No. gram/liter ml/liter from 7.5% Solution
11-025-1 2.2 29.3
11-040-1 2.2 29.3
11-042-1 2.2 29.3
11-050-1 3.7 49.3
11-055-1 3.7 49.3
11-058-1 3.024 40.32
11-060-1 2.75 36.67
11-075-1 2.2 29.3
11-080-1 2.2 29.3
11-085-1 0.35 4.67
11-090-1 1.2 16
11-095-1 1.176 15.68
11-100-1 2 26.67
11-115-1 - -
11-170-1 1.2 16