Cosmetics Formulation Development

Please ask for knowledge why Niacinamide cannot be formulated simultaneously with formulas containing L-ascorbic acid if the formula containing the above two components is combined in the same formula. What reaction will cause the serum? Or will it affect the face in any way? If in the formula there are 2 substances above mixed in the same formula? What serums are there currently? Niacinamide and L-ascorbic acid up total It's in the same formula. Thank you.

Hello Niacinamide + ascorbic acid will become to Niacinamide ascorbate, which is currently according to known information No benefit to the skin Combining them in the same formula should not be done.