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).
Joyce Maso presents Professor Reinhold Dauskardt with the Henry Maso Award Lecture Certificate.
“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. Arabinoxylo-oliogosaccharide inhibits 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 uses imaging quantification in its in-vivo laboratory to highlight the cosmetic efficacy of its natural active ingredients.
A Look at Hair
SCC vice president Joe Dallal of International Specialty Products moderated a session devoted to hair. According to Trevor Evans of TRI-Princeton, large molecules such as surfactants, polymers and oils dominate hair care chemistry.
“But water is a small molecule and affects hair more than anything I know,” he told the audience before launching into his presentation on how chemists can manipulate the bulk properties of hair by utilizing small molecules such as glycerol, glycolic acid and lactic acid.
Gina Cosby presents Brian Czetty with the SCC Award sponsored by Rhodia.
Michael Philbin, AkzoNobel Surface Chemistry, explained how polymer compositions made by polymerizing vinyl pyrrolidone in the presence of maltodextrin delivered similar performance in a hair gel to PVP with a K value of 30. It indicates that a performance equivalent to commonly used synthetic polymers can be achieved from a polymer having a natural component of more than 50% of its composition.
Carole Lepilleur, Lubrizol Advanced Materials, explained how cationic cassia polymers can enhance deposition. In the Lubrizol tests, cationic cassia polymers (at 1.5%) deposit silicone much more efficiently than cationic guar or PQ-10. As a result, formulators can use less silicone and cationic polymer than formulations based on the benchmarks to achieve at least comparable if not better conditioning performance (For a detailed look at this chemistry, see p. 84, Happi, December 2010).
Friday’s sessions got underway with presentations devoted to the role of genomics in personal care chemistry. Philip Ludwig of Arch Personal Care explained how human genomic microassays can identify effective ingredients for personal care. These microassays give cosmetic chemists new opportunities to examine the influence of skin ingredients on skin cells in ways that were not previously possible. In the Arch study, researchers reviewed more than 200 genes related to skin function in order to examine the influence of skin lighteners on melanocytes.
“Human microassays can help guide your research,” he told the audience. “Gene expression and protein expression usually correlate.”
A 24-hour topical treatment of three skin lighteners—hydroquinone, kojic acid and niacinamide—on melanocytes demonstrated a significant upregulation of the tyrosinase gene, which was demonstrated in protein assays as well. In addition, a critical iron binding protein gene, Ferritin (FTH1), was significantly upregulated in the gene assays as well as in protein assays, suggesting a role for iron in melanogenesis that was not previously appreciated, according to Ludwig.
ISP has developed a new peptide to maintain expression of clock genes in conditions of stress-induced desynchronization by UVB or aging. According to Isabell Imbert, this development provides insights supporting the key role of clock and sirt-1 in chromatin remodeling, which plays a role in DNA repair. When applied twice a day at a 1% concentration, the material protected and repaired DNA, which significantly reduced UVB-induced damage. Moreover, positive modulation of clock gene expression leads to improved cellular metabolism as assessed by a 33% increase in collagen III production.
Southern Mississippi Student Earns Top Poster Award at Scientific Seminar
The Student Poster Showcase is held annually to promote student research in the cosmetic industry. This year there were
Members of the Committee on Scientific Affairs judged the posters and the award for First Place went to Vipul Padman, University of Southern Mississippi for his poster entitled “The Effect of Polymer Backbone Rigidity and Hydrophilicity on Polymer-Surfactant Interaction and Phase Behavior.” Second Place was awarded to Jennifer Karr, University of Cincinnati, for
her poster entitled “Modification of Skin Absorption while Maintaining
Effective Evaporation Rates for N,N-diethyl-3-methylbenzamide (DEET) using a Novel Encapsulation Method.”
Third Place was awarded to Kathleen Davis, University of Southern Mississippi for her poster entitled “Effects of Carbomer on the Phase Behavior of Oil/Water/Poloxamer 184 Systems.”
Fourth Place was awarded to Rania Ibrahim, University of Cincinnati for her poster entitled “Dermal Clearance Model for Epidermal Bioavailability Calculations.”
According to Metabolon’s John Ryals, global metabolomics can help chemists create more effective products. Global metabolomics provides details of metabolismin biological systems and can be used to identify biochemical changes associated with aging, inflammation, tissue damage and repair, wound healing and skin diseases. Ryals said that metabolomics has applications in determining mechanism of action, safety and claims support.
“Metabolics can be used to identify biomarkers associated with aging, photodamage and wrinkles,” said Ryals, who noted that his company also worked with Colgate to identify effective active ingredients for oral care. That study found that Colgate Total significantly decreased the levels of inosine, lysine, putrescine and xanthine at gingivitis sites in as quickly as one week.
Another way to assess cosmetics is via synchrotron light. Vivian Stojanoff of Brookhaven National Laboratory explained that synchrotron radiation provides a wide selection of non-destructive methods and techniques that are particularly well adapted to molecular structure and chemical analysis, and cell and element distribution imaging.
The SCC Scientific Seminar was probably the last industry event to take place prior to the release of the US Food and Drug Administration’s action on sunscreens (see The Sunscreen Filter, p. 46 in this issue). Sun care was the topic of the final session of the seminar and was moderated by Lintner.Nava Dayan of Lipo Chemicals detailed results of a study to investigate the in vitro phototoxic effects of fractionated melanin and chlorpromazine HCl in three different cell lines: mouse embryonic fibroblast cell line, primary dermal fibroblasts and primary human keratinocytes.
“Fractionated melanin was found to be non-phototoxic in both the mouse embryonic fibroblast cell line and the primary human keratinocytes,” said Dayan.
In contrast, primary dermal fibroblasts showed little difference between light and dark controls. Meanwhile fractionated melanin did not show signs of toxicity or phototoxicity in either the mouse embryonic fibroblast cell line or the primary human keratinocytes; a finding that assures its safety as a cosmetic ingredient, according to Dayan.
Honoring Theresa Cesario
During the awards luncheon, SCC president Randy Wickett announced that the Society would honor Theresa Cesario, its long-time executive director, by renaming the luncheon The Theresa Cesario Awards Luncheon. Cesario died suddenly on Jan. 16, 2011. During the luncheon, the Society of Cosmetic Chemists’ Award, which recognizes the best paper presented at the 2010 annual scientific meeting, was awarded to Brian Czetty, Jeffery Domsic and Greg Hillebrand, Procter & Gamble (P&G), for the paper, “Powered devices for facial cleansing: should they occupy space in the facial cleansing device toolbox?”
The award was sponsored by Rhodia Novecare.
The scientific seminar’s final speaker, consultant Nick Morante, explained how light diffusion can be used to diminish the appearance of lines and wrinkles. Ingredients such as interference pigments, glass beads, spherical silica, aluminum oxide and multilayered particles can provide instant results for the consumer and are less expensive than anti-aging active ingredients, according to Morante.