I would like to make a dermal tea tree oil formulation (<10%) in water, which also will contain a small concentration of surfactants to help solubolize the tea tree oil. In addition, I would like to add some agents to increase the dermal penetration of the tea tree oil.
My question is, what penetration enhancers do people recommend? I have read about propylene glycol, diethylene glycol monoethyl ether, ethanol and oleic acid as all being good enhancers. So I may consider adding one or more of these at concentrations lower than 5%.
Does anyone have experience in this topic?
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