One of the reasons for making Vitamin C serum at home is to save tons of money, and to KNOW what it is you are putting on your face. Using Vitamin C in the form of ascorbic acid is best form to use (if pure, it is also edible), but, as I've described in a previous post, this form is also unstable in the presence of air, heat and water. I noticed that each time I made an individual batch, it lasted 2-3 weeks before I would start seeing the faintest sign that my preparation was oxidizing. At that point, I stopped using it and would make another batch using the same materials, and it would again take 2-3 weeks before it would start turning color.
So I asked myself, if the powdered ascorbic acid was being protected from oxidation by being stored closed, in the dark and in a refrigerator:
1) Would the newly prepared Vitamin C serum, also be protected?
2) How long would this protection last, and could I therefore make a larger batch at one time and just use it
throughout that time, instead of making individual batches every 2 weeks?
SO, this was my plan...I made several months worth of the serum, then loaded multiple small eyedropper bottles with the serum. I pulled out a new bottle every 2 weeks until the bottle I used started turning color.
I made this bulk batch on Sept 12, 2015, and the serum I removed from the refrigerator on December 12, lasted about 4 days before I sensed the color change. So, yes, it appears that the temperature of the refrigerator slowed down the oxidation process to allow a batch of the serum to be used for 3 months instead of 3 weeks. For this reason, I give this serum an expiration date of 3 months. So glad I found this out...this will save anyone who tries this, a great deal of time and effort!
You can either do what I did and buy several eyedropper bottles, or buy 1-2 and clean them out between uses.
The recipe I used is listed below:
Vitamin C, HLA, DMAE, Niacinamide Serum - by BNSS
Distilled water 15 tsp
** LAA (L-Ascorbic Acid) 19.2 grams(= final concentration of ~ 19.5 %)
Hyaluronic Acid (***LMW) 1.92 grams(= final concentration of 1.0 %)
* DMAE (bitartrate) 1.6 grams (= final concentration of 1.7 %)
* Vitamin B3 (Niacinamide) 0.96 grams (= final concentration of 1.0 %)
* also added to boost the anti-wrinkle effects of the serum
** To help the Vitamin C dissolve, take 20 grams and grind it to a fine powder
*** LMW = Low Molecular Weight of 800,000 to 1,000,000 Daltons
1) Place room temperature distilled water into a glass container which holds ~100ml, and can be tightly closed (suggestion: use an jelly jar. It should be glass) . Stir every hour or so. It might take several days to dissolve completely, depending on how fine your vitamin C is.
2) Add DMAE and Niacinamide and stir every hour or so until dissolved.
3) Add Hyaluronic Acid (HLA) by sprinkling on top and allow to sit on the top of the solution until most has sunk in or appears to be a gelatinous mass in the center serum. Do not swirl when still in powder form as it will stick to the glass and may not reach the liquid in order to get dissolved. Once it is all "wet" it can be stirred.
On the label, write on the label, the name of the product, the date the serum was completed, and add the expiration date, which is 3 months after production.
4) Mix well then add ~2 tsp, or whatever will last 2 weeks, to your eyedropper bottle. Tightly close the remainder of your batch and place in the refrigerator. Use in the morning and evening. I had extra, so I gave some away, but make sure whoever receives this gift from you, understand that at room temperature, it is good for only 2-3 weeks.
This page will be updated as additional data is discovered.