L-Ascorbic Acid (Regular vs Ultra-Fine): Solubility, Efficacy, and Formulation

Asked by: pantawan_kantiyatep On: December 22, 2014 Product Type: Cosmetics

Question

What are the differences between L-Ascorbic Acid (regular) and L-Ascorbic Acid Ultra-Fine, particularly regarding solubility and efficacy? How does heat affect dissolution and stability? Which type is suitable for formulations containing water, such as the referenced skinceuticals-c-e-ferulic formula?

Answer

Based on the conversation:

  1. Solubility and Dissolution Time: L-Ascorbic Acid (regular) is soluble in water. The Ultra-Fine version differs mainly in particle size, which impacts dissolution ease, especially in formulas with limited water. The price difference is due to the processing for the Ultra-Fine version.
  2. Efficacy: The efficacy of Vitamin C (L-Ascorbic Acid) is the same for both regular and Ultra-Fine types. The difference is in how easily they dissolve depending on the formula.
  3. Effect of Heat: Using heat (50-70°C for 1-3 minutes) can aid dissolution. However, Vitamin C is heat-sensitive and can degrade. It's generally best to avoid heat or use it minimally if necessary.
  4. Recommendation: If your formula has enough water to dissolve regular L-Ascorbic Acid, you can use the regular type to save cost, as efficacy is identical. The Ultra-Fine type is for formulas lacking sufficient water for regular dissolution. For your proposed formula and the referenced skinceuticals-c-e-ferulic formula, the regular Vitamin C (L-Ascorbic Acid) can be used.