An Ionic Liquid Nanoparticles for Dermal Targeted Delivery and Effective Anti-wrinkle Treatment

Aging is a natural process that cannot be stopped but retarded. Hydroxypinacolone retinoate (HPR) is a potent anti-wrinkle agent, but with severe irritancy, low stability, and poor water solubility, making it hard to apply in cosmetics. Ionic liquid (IL), as a solvent, displayed improved transdermal efficiency. The role of nano-encapsulation technology in addressing the disadvantages of efficacy application is significant. Using a combination of ionic liquids and nano-encapsulation technology to obtain HPR-encapsulated ionic liquid nanoparticles (HPR IL-NPs) is an innovative formulation used as a serum, emulsion, and cream in cosmetics for effective anti-wrinkle. HPR IL-NPs were prepared using matrine coconut oil ionic liquid as a surfactant and permeation enhancer combined with high-pressure homogenization. The average particle size in the obtained HPR IL-NPs was 92.8 nm. Applying the HPR IL-NPs increased the content of active substances in the skin by 3.6-fold compared to a traditional HPR-loaded cream. The chick chorioallantois membrane assay showed an RC50 > 100%, and repeated skin-irritation tests resulted in a mean value of 0.00 points per animal per day. The HPR IL-NPs showed continuous release for 24 hours in vitro in the continuous release test. At the same time, the HPR IL-NPs significantly reduced irritation induced by HPR alone. The number and area of facial wrinkles decreased by 25.09% and 23.65%, respectively, after one week of application of liquid cream on volunteers. IL NPs can significantly improve transdermal absorption efficiency, reduce irritation, and demonstrate high anti-wrinkle efficiency. Supramolecular liquid cream is a promising product in cosmetics for skin care.