Formulation and Optimization of Nanoemulsions Loaded with Gamma−Aminobutyric Acid (GABA) for Dermatological Application: Assessing Skin Permeation and Penetration Enhancement

Gamma−aminobutyric acid (GABA) presents several potential skin benefits, but its water−soluble nature poses challenges for effectively penetrating the skin to produce its effects. This research aimed to improve GABA’s skin penetration and availability by employing a nanoemulsion formulation, both with and without the aid of the penetration enhancer 1,8−cineole. Using a high−pressure homogenizer, an oil−in−water nanoemulsion was created, and its size and distribution were analyzed. The stability of these nanoemulsions was tested under various conditions, revealing their resilience over six months, even at elevated temperatures of 40 °C. In vitro tests on pig skin showed that GABA−loaded nanoemulsions, particularly those without the enhancer, demonstrated a nearly 2.89−fold increase in skin permeation compared to the solution form. Moreover, the addition of the enhancer amplified this effect, resulting in over a 3.37−fold increase in skin permeation compared to the solution. These results emphasize the potential of nanoemulsion formulations as effective tools for enhancing GABA’s skin permeation and availability, potentially expanding its use in dermatological applications. Further exploration and research are necessary to fully exploit GABA’s capabilities in supporting skin health and wellness.