[ngarayeva001]

@MJL I make a serum with even more ingredients and there is no powdery feel. I think your main problem is Allantoin. Consider reducing to 0.3% and dissolve it in propanediol and heat it (60-70C?). Then add to your water phase and heat it to 50 C. Also, potentially reduce Hyaluronic to 0.5%. It will still be viscous enough for a serum. I assume that you are using high molecular weight. Niacinamide never causes any issues. I even used 10% without a powdery feel.

[ngarayeva001]

Hi MJL,

The Ordinary adds Dimethyl Isosorbide to their Niacinamide serum to increase the penetration. Check their products. Since they are very effective I believe it can be used as a reference. Btw Glucosamine made my niacinamide serum orange. I posted a question here and still waiting for an answer.

Also, both lotioncrafter and makingcosmetics have ceramides complex that you can add to your serum. It is my personal experience (I am not a chemist) but topical ceramides make difference.

Best,

[ngarayeva001]

Hi MJL,

I had the same question a while ago and also could not find much. I use 1% of Dimethyl Isosorbide in a serum that I have been using for four months. It does not cause any sensitivity (my skin is not sensitive though). The lotioncrafter website recommends the usage of 1 to 10%.

Another reference point, The Ordinary have a product that is to be used under eyes and it includes Dimethyl Isosorbide. 

Caffeine Solution 5% + EGCG

I do not think that they use more than 1%. I use the ordinary’s ingredient lists a lot for a reference. Keep in mind that Dimethyl Isosorbide decreases viscosity significantly.

I hope it’s helpful.