For Break Outs?
Not to mention wrinkles and age spots. The mapping of the human genome is
creating new opportunities for cosmetic chemists to create effective formulas for a
variety of personal care problems.
Tom Branna • Editorial Director
CALL IT THE GENOME EFFECT. The mapping of the human genome a decade ago was hailed as a breakthrough for the medical field. Turns out, it
may start paying dividends for the global
cosmetics industry, too. The genome was
just one topic of presentations at the Society of Cosmetic Chemists’ Scientific Seminar, which was held in Las Vegas last
month. The seminar attracted approximately 270 chemists from the US and
around the world. The program included
sessions on skin, hair and sun care, along
with the aforementioned genomics. Karl
Lintner, president of Kal’Idees, served as
chairman of the Committee on Scientific
Affairs. Randy Wickett of the University of
Cincinnati, is president of the Society.
The seminar opened with a session on
skin that was moderated by Howard Epstein of EMD. Reinhold Dauskardt of Stanford University delivered the Henry Maso
keynote award lecture. Dauskardt noted
that so little is known about how skin behaves at the biomechanical level. Nevertheless, he took the audience on a
fascinating trip of skin damage and the effect of cosmetic treatments. Dauskardt
pointed out that skin is extremely sensitive
to moisture, calling it a composite system
that is very stiff (stratum corneum) over a
very compliant layer (epidermis and dermis). For example, the SC absorbs water
readily and buckles as the moisture level increases. In contrast, it cracks easily when
moisture is lacking.
Too often, however, cosmetic chemists
must rely on non-technical jargon to explain the skin’s condition. To overcome this,
Dauskardt explained a cadre of thin-film
methodologies to quantify skin stiffness,
stress and fracture resistance. Resistance to
damage, for instance, can be measured
using intercellular delamination. A typical
cosmetic ingredient that delaminates corneocytes is sodium lauryl sulfate (SLS).
“The stresses on the stratum corneum
can be completely explained by the amount
of water in the tissue,” he noted. Therefore,
strategies to promote or maintain skin hydration, including occlusive agents and
Joyce Maso presents Professor Reinhold
Dauskardt with the Henry Maso Award Lecture
emollients, are paramount. For example,
the amount of UV damage can be correlated to the amount of moisture in the skin.
Dauskardt noted that the stiffness of the SC
doesn’t change when damaged by UV, but
the lipid content is lowered. That results in
a weaker SC that is more prone to fissures.
“The stratum corneum is a barometer
of the amount of moisture in the environment,” he concluded.
With controversy surrounding hydroquinone, chemists are searching for an effective skin whitener. Romain Reyaud of
Soliance explained that arabinoxylo-oliogosaccharide actually works better than kojic
acid and works faster than arbutin, which
was confirmed in a clinical study involving a
panel of 22 middle-aged Asian women who
applied a cream containing 3% arabinoxylo-oliogosaccharide vs. 2% arbutin.
melanogenesis through its action on TRP-
1 (an enzyme involved in melanogenesis)
and tyrosinase. The material is also readily
biodegradable and Ecocert-validated.
But how does one measure these materials? David Boudier of Silab explained
how digital imaging is being used to quantify cosmetic effects. The imaging quantification process involves three key steps:
acquisition, via fluorescence microscopy;
digital photographs or fringes projection;
processing, i.e., contrast enhancement and
noise filtration; and analysis, such as comparison of variances of paired or independent samples. Boudier explained that Silab