Formulation and Evaluation of Radiance Serum Containing Astaxanthin–Zeaxanthin Nanoemulsions as an Anti-Wrinkle Agent: Stability, Ex Vivo, and In Vivo Assessments

Reactive oxygen species (ROS), commonly known as free radicals, induced by UV radiation can compromise the dermal structure, leading to a loss of skin elasticity and subsequent wrinkle formation. A promising strategy to prevent and mitigate skin aging involves the use of topical formulations with potent antioxidant properties. Secondary metabolites such as astaxanthin and zeaxanthin are known for their robust antioxidant activities, which surpass those of tocopherol, offering significant benefits for skin health and protection against UV-induced damage. These properties suggest their potential application in anti-aging products. This study aims to evaluate the stability, ex vivo penetration, and in vivo efficacy of a radiance serum containing an astaxanthin–zeaxanthin nanoemulsion (AZ-NE) designed as an anti-wrinkle agent for topical application. The research was conducted in four stages: production of the astaxanthin–zeaxanthin nanoemulsion (AZ-NE), formulation of the AZ-NE radiance serum, stability, and efficacy testing. In this study, the formulated radiance serum demonstrated stability over three months under specified storage conditions. Ex vivo penetration studies indicated efficient diffusion of the active ingredients, with astaxanthin showing a penetration rate of 25.95%/cm2 and zeaxanthin at 20.80%/cm2 after 120 min. In vivo irritation tests conducted on human subjects revealed no adverse effects. Moreover, the serum exhibited substantial anti-wrinkle efficacy, with 15 female participants experiencing a wrinkle reduction of 80% to 93% over a 28-day period.