The cosmetics industry is very dynamic with new active ingredients constantly added to the material inventory that formulators have at their disposal.
However, they will not achieve the desired effect unless delivered from suitable products and this feature focuses on how they can be optimised to target the relevant skin cells.
The first question to ask is: what does the formulator wish to achieve? In cosmetics, the main concern is to reach cutaneous cells while limiting the passage into the blood circulation.
The objectives of topical therapy can therefore be classified into two major areas: to modulate or assist the barrier function of skin and to administer an active ingredient to one or more skin layers while minimising systemic involvement.
The stratum corneum (SC) is an effective barrier of stratified skin cells that has evolved to stop penetration of undesirable material into the subcutaneous layers of skin.
It suffers from dehydration, excessive exfoliation (or, conversely, failure to exfoliate) and inflammation caused by