Multifunctional active ingredient-based delivery systems for skincare formulations: A review

Nowadays, there is a growing demand for effective cosmetic skincare products that can address the specific skin problems of consumers. Delivery systems play an important role in the effective action of cosmetic skincare formulations. Delivery systems are attractive and smart technologies used as carriers for cosmetic ingredients, which are sensitive to various physical factors such as light, oxygen, pH and temperature. Delivery systems offer several advantages: transport and protection of sensitive active compounds, controlled and targeted release of active ingredients. Several delivery systems, varying in chemical composition, with adaptable physicochemical characteristics (size, morphology, zeta potential, structure) as well as great advantages as carriers, are developed and described in the literature. This article reviews the current cosmetic active ingredients used in skincare products due to their beneficial properties such as antioxidant, anti-aging, photo-protective, anti-inflammatory, anti-microbial, etc.). In addition, the main advantages of several classes of delivery systems (emulsions, lipid nanoparticles, polymeric particles) are described, as well as some recent approaches used to ensure their efficacy (long-term stability, controlled release of the active, skin penetration/permeation) are reviewed. Finally, new trends to be considered for the development of delivery systems and cosmetic formulations are discussed.