Vitamin C - Magnesium Ascorbyl Phosphate
Water soluble, stable Vitamin C
INCI: Magnesium Ascorbyl Phosphate
Magnesium Ascorbyl Phosphate (MAP) is a stable, water soluble derivative of Vitamin C, it does not readily degrade in formulas containing water. It is also considered light-stable and oxygen-stable.
Studies of MAP in aqueous solutions have indicated that it retains over 95% of its potency at 40°C without any pH adjustment.
MAP is capable of suppressing skin pigmentation by inhibiting Tyrosinase activity thus making it effective in whitening dark skin, or areas of dark skin. However, it has been sugested that concentrations of up to 10% may be required to be effective at inhibiting melanin production.
MAP appears to have the same potential to boost skin collagen synthesis as does Ascorbic Acid, but at lower concentrations. As such, it may be the preferred choice for those with sensitive skin or those wanting to avoid the exfoliating effects of highly acidic Ascorbic Acid.
Magnesium Ascorbyl Phosphate (MAP) may discolor in formulations with a pH below 6, so is best used in products with a final formulation pH between 6.0 - 7.0.
The solubility of MAP in water is up to 15.4% at 25°C
MAP is stable at 80°C for up to 20 hours so it can be added to the water phase prior to heating.
You can also predisperse it in a small amount of distilled water and add at the end of the formulation process.
If you're having trouble dissolving MAP in water, warming the solution to about 40°C (104°F) will help.
Typical usage rate: 0.2 - 3, up to 10%
pH: 7.0 - 8.5
Solubility: Soluble in water, mix well, allow time for lumps to dissolve