TLDR The microemulsion delivered the dye deeper into the skin than the cream.
The study compared the penetration and localization of the lipophilic dye curcumin when applied in an oil-in-water (o/w) microemulsion versus an amphiphilic cream on the skin of 6 human volunteers. Using tape stripping and laser scanning microscopy, it was found that the microemulsion allowed deeper penetration into the stratum corneum (SC) and hair follicles, with significantly less curcumin remaining on the skin surface compared to the cream. The microemulsion facilitated penetration into the complete follicular infundibula, whereas the cream only reached the follicular orifices. This indicated that lipid layers and follicles are preferred pathways for the lipophilic dye in the microemulsion.
61 citations,
March 2006 in “Colloids and surfaces. B, Biointerfaces” Lecithin microemulsion safely delivers tetracaine hydrochloride through the skin.
32 citations,
November 2004 in “Journal of pharmaceutical sciences” Different tea tree oil mixtures absorb into hair follicles at varying levels, with microemulsion being the most effective.
69 citations,
January 2002 in “Journal of biomedical optics” Dyes can penetrate human skin and hair follicles up to 1.2 mm deep and the sebaceous gland can store dye; Indocyanine Green lotion was made for safe dyeing and monitoring.
82 citations,
January 2002 in “Journal of drug targeting” Drugs penetrate scalp skin better than abdominal skin, with scalp hair follicles aiding in higher drug delivery.
2 citations,
May 2023 in “Nanomaterials” Microemulsions could improve skin drug delivery but face challenges like complex creation and potential toxicity.
54 citations,
June 2020 in “Pharmaceutics” New nanocarriers improve drug delivery for disease treatment.
36 citations,
September 2019 in “Journal of Herbal Medicine” Herbal nano-formulations show potential for effective skin delivery but need more research.
67 citations,
January 2022 in “Theranostics” Advanced nanocarrier and microneedle drug delivery methods are more effective, safer, and less invasive for treating skin diseases.
39 citations,
September 2016 in “Expert Opinion on Drug Delivery” New drug delivery methods can make natural compounds more effective and stable.