Size-Dependent Penetration of Nanoemulsions into Epidermis and Hair Follicles: Implications for Transdermal Delivery and Immunization

The study investigated the size-dependent penetration of nanoemulsions into the epidermis and hair follicles, revealing that smaller nanoemulsions (80 nm) penetrated deeper (up to 588 μm) and more efficiently compared to larger ones (200 nm and 500 nm). The 80 nm nanoemulsions also showed better interaction with antigen-presenting cells, indicating their potential for transcutaneous immunization (TCI). The findings suggested that nanoemulsions smaller than 200 nm are advantageous for dermal drug delivery and TCI due to their superior penetration and interaction with immune cells.