the environment, it isn’t completely impene-
trable. The top layer is made up of tightly
packed cells cemented together by lipids, so for
an ingredient to pass through this top layer it
needs to either be absorbed by the skin cells or
find a way through the small lipid gaps between
the cells, which is where molecule size comes
into play. can be both synthetic and natural in composi-
tion, such as Jojoba Oil, and can significantly
improve the potency of topical ingredients. This
is why the technique is so popular when it comes
to antioxidant serums: the lipid bubble protects
a volatile ingredient like Vitamin C from being
broken down to ensure your skin reaps more of
its benefits.
The smaller the molecule, the easier it will
penetrate the surface of the skin. Small mole-
cules or those with a low molecular weight can
squeeze through any gaps in this lipid glue
while larger molecules remain at the surface,
either being slowly absorbed by the cells or
sitting on top. For scientists, the ideal weight
of a molecule that can penetrate the skin is
around 500 Daltons (Daltons are a unit of meas-
urement used to determine the mass of a mol-
ecule or atom). Most experts say that ingredients
with a molecular weight greater than this can’t
penetrate the skin’s lipid layer and therefore can
go no further than the stratum corneum. This
is fine for rich moisturisers that are designed to
combat surface dryness and prevent moisture
loss, but it’s not so good for antioxidant serums
that need to go deeper. Encapsulation can also be used to make inten-
sive ingredients more tolerable for the skin by
using time-release technology. By releasing an
active ingredient like Retinol slowly into the
skin, there is less chance of a severe reaction
taking place, something the scientists at Medik8
keep in mind when developing any Vitamin A
product. “Retinol is not without its problems
and can often cause irritation. Because of this,
we’ve included time-release technology (in all
Medik8 Retinol products) which essentially
drip feeds Retinol into the skin slowly over-
night, thereby reducing the risk of irritation,”
explains Formulation & Development Director
Daniel Isaacs. “Our Crystal Retinal products
have a patented time-release delivery system
that encapsulates the ingredient Retinalde-
hyde in a crystal molecular vehicle that is
broken down by the skin’s natural enzymes
upon contact. This unique action controls
the release of the active to ensure the formula
remains stable, absorption is optimised and
the highly-potent formula is distributed
evenly and constantly throughout the night.”
It’s also easier for oil-soluble molecules to pen-
etrate the skin compared to water-soluble ones,
due to the skin’s outermost lipid layer. For
example, Salicylic Acid is oil-soluble, which is
why it can successfully penetrate into the pores,
but an AHA like Lactic Acid is not and so does
the majority of its work at the surface. But,
scientists have found a way around this.
Encapsulation Techniques
To ensure ingredients that are unstable or too
large in molecular structure can reach the lower
layers, scientists use micro-encapsulation to aid
their delivery to the layer of the skin that can
utilise them most effectively. Encapsulation
involves encasing a molecule within a lipid
sphere or bubble, to protect the fragile molecule
hidden inside from damage and from being
broken down too early, while also simplifying
its path into the skin. These protective bubbles
Sounds amazing, right? But not every ingredi-
ent needs to be encapsulated to work. AHAs,
essential oils, peptides and low molecular weight
Hyaluronic Acid can all transform the skin
without using encapsulation methods, while
some products work their best at the surface.
Products like sunscreens, healing balms and
cleansers that, by design, are washed off before
any active ingredients have time to penetrate
the surface, are all beneficial despite their ina-
bility to reach the lower layers of the skin. For
all-round skin health, try to include a mix of
products that address your biggest complexion
concerns at and below the surface.
ISSUE #10 | 2019 | SkinHealthMagazine.com 35