# Applicability of Nanoemulsions for the Incorporation of Bioactive Compounds in Cosmetics: A Review

## TL;DR

This review explores how nanoemulsions can help incorporate skin-friendly plant compounds into cosmetics to combat aging and environmental damage.

## Contribution

The paper reviews the use of nanoemulsions to enhance the delivery of bioactive compounds in cosmetics, focusing on their benefits and challenges.

## Key findings

- Nanoemulsions improve the solubility and stability of lipophilic bioactive compounds in cosmetics.
- They enhance skin penetration and bioavailability of antioxidants like phenols and flavonoids.
- Nanoemulsions are suitable for antiaging and protective cosmetic products like creams and sunscreens.

## Abstract

Plants are important
sources of metabolites used in the cosmetics,
food, and pharmaceutical industries, especially in cosmetics, where
bioactive compounds offer benefits for the skin, such as protection
against environmental stresses. The term “cosmeceutical”
has emerged to describe products that combine aesthetic effects and
dermatological treatments. With the growth of the cosmetics industry,
the demand for ingredients that combat the signs of aging and oxidative
stress – the main cause of skin aging – has increased.
Bioactive compounds, such as phenols, flavonoids, and carotenoids,
have antioxidant properties that are widely used to control the skin’s
aging process, triggered by environmental factors or the body’s
own metabolism, leading to excessive production of free radicals and,
consequently, oxidative stress. However, incorporating these lipophilic
compounds into water-based cosmetic formulas presents major challenges,
including poor solubility, low stability, limited skin penetration,
and rapid degradation. Nanoemulsions overcome these limitations by
enabling droplet sizes of 20–200 nm through high-energy (e.g.,
high-pressure homogenization, ultrasonication) or low-energy (e.g.,
phase inversion temperature, spontaneous emulsification) methods.
Their significance in cosmeceuticals lies in enhanced skin penetration,
improved bioavailability of lipophilic actives, and prolonged product
stability, making them ideal for antiaging creams, sunscreens, and
moisturizers. This review article aims to address antioxidant compounds,
their cosmetic applications, and the techniques used to obtain them,
including characterization methods, validation of nanoemulsions, the
main difficulties, and future prospects.