Thanks to this forum I do not have any issues with dissolving Salicylic acid in water. I used a mix of water\glycerin\propylene glycol\betaine\sodium citrate and some pH adjuster to dissolve it, but recently I found some old comment here, which claims that sodium citrate is actually neutralizes the acid instead of increasing it's solubility. Is this true? I remember some info from school's chemistry, that some strong acid can replace weaker acids in salts, but not sure I remember it correctly and it applies here.
Also, most of Korean brands use betaine salicylate in their products due to regulation laws. So I wonder if salicylic acid can react with betaine just in water or there should be some special reaction chains and I do not need to worry that SA in my formula is actually betaine salicylate?