To make 4oz (120 mL) of serum containing 3% DMAE, you will need about 10 gm DMAE bitartrate (the rest will be the tartaric acid).
DMAE Bitartrate added directly to a base cream will probably turn the cream into a runny lotion. To prepare a DMAE cream, mix the DMAE first with Sea Kelp Coral, then combine the mixture with the cream. Try a little at a time so that your cream does not liquify, unless you don't mind using it as a lotion.
DMAE improves the firmness of the skin and helps reduce the visual appearance of sagging skin, although the mechanism of action is unknown. It is an amine-based alcohol, a precursor to the neurotransmitter acetylcholine, present in nerve tissue in small amounts and more abundant in fish. DMAE acts as a free radical scavenger due to the high electron content of its nitrogen atom. Once phosphorylated, DMAE is incorporated into the membrane of cells. In addition, DMAE is an immediate precursor to choline, which is involved in cell membrane biosynthesis.*
(*See reference tab for scientific resources)
R. Grossman The role of dimethylaminoethanol in cosmetic dermatology. Am J Clin Dermatol. 2005;6(1):39-47