Vitamin C Differences

• Ascorbic Acid / L-Ascorbic Acid: These terms generally refer to the same pure form of Vitamin C. L-Ascorbic Acid is the biologically active form. It is known for its high effectiveness in brightening skin, reducing wrinkles, and acting as an antioxidant. However, it is highly unstable, especially in water, and requires specific conditions (low pH, absence of water or use of stabilizers) for formulation stability. Different grades (Standard, Fine, Ultra-Fine) mainly differ in powder size, affecting how easily they dissolve or disperse. The Ultra-Fine grade (Product ID 133) is processed to be very small (under 45 microns) for better dispersion, particularly in anhydrous (water-free) formulas.
• Ethyl Ascorbic Acid (3-O-ethyl ascorbic acid): This is a stable derivative of Vitamin C. Unlike L-Ascorbic Acid, it is highly stable and easily dissolves directly in water. It offers good skin brightening effects by reducing melanin production and can help reduce age spots. It is easier to formulate with due to its stability but may be considered moderately effective compared to pure L-Ascorbic Acid at the same concentration, although its stability can make it more effective over time.

In summary, L-Ascorbic Acid is the potent but unstable pure form, while Ethyl Ascorbic Acid is a more stable and easy-to-use derivative.

Your Formulation

You mentioned a target formulation with Propanediol, ascorbic acid, and Alpha-Arbutin and noted that "ascorbic acid" might not be available.

Based on the product information, L-Ascorbic Acid is available on the website under names like "Vitamin C (L-ascorbic acid)" in different grades (Standard, Fine, Ultra-Fine). The link you provided for "ascorbic acid" actually points to "Vitamin C (L-ascorbic acid) (Ultra-Fine)" (Product ID 133).

Your desired ingredients are available:

• Propanediol (1,3-Propanediol) (Product ID 1337) is available and can function as a humectant, solvent, and preservative booster.
• L-Ascorbic Acid is available in various grades (Product IDs 133, 134, 941). For ease of formulation, especially if you are dissolving it, the Ultra-Fine (Product ID 133) or Fine (Product ID 134) grades might be easier to work with than the Standard grade (Product ID 941) due to their smaller particle size. Remember that L-Ascorbic Acid requires a low pH (2.0-4.0, but FDA recommends at least 3.5 for skin application) for stability and effectiveness.
• Alpha-Arbutin (Product IDs 68, 889, 6186) is also available. It is a water-soluble skin brightening agent that works by reducing the enzyme Tyrosinase. It is considered safe and effective for reducing melanin production.

Therefore, you can proceed with your formulation using Propanediol, one of the L-Ascorbic Acid grades (Ultra-Fine or Fine recommended for easier dispersion), and Alpha-Arbutin. Pay close attention to the pH requirements for L-Ascorbic Acid to ensure the stability and effectiveness of your final product.