ABSTRACTS 401 mice. 24 and 48 hr. later skin fragments were pulse labelled with 35S-methionine to assay total protein production. After labelling, proteins were extracted and separated using 2-dimensional gel electropho- resis with isoelectric focussing in the pH range 5-7 in the first dimension, and 10% polyacrylamide gels in the second dimension. Using this technique we were able to detect over 100 individual proteins under control, TPA, An, and BP treated animals. TPA and An treatment were found to alter the production of at least 10 distinct proteins, 9 of which appear to be keratins. BP treated epidermis closely resembled control skin, suggesting that it may act by a mechanism differing from that of TPA and An. Further studies using pulse labelled skin fragments should facilitate the characterization of proteins involved in the skin irritation process and the mechanism by which BP and An act. An alternative to direct panelist-judge interac- tion in evaluating underarm deodorants S. Mark Henry, Ph.D., G. Jacobs, and V. F. Cotty, Bristol-Myers Products, 225 Long Avenue, Hillside, NJ 07207 This report describes a novel method which elimi- nates the unpleasant and problematical close con- tact between deodorant panelists and judges. Instead of direct sniffing of the axilla, samples of axillary secretions are obtained using the bottom end of disposable glass tests tubes rotated briefly in the axillary vault. The tubes are removed, then handed to judges positioned out of sight of the subjects. The judges then score each pair of tubes and record their data. Results correlate well with tests conducted in the conventional manner. In addition to eliminating the potential problems of subject-judge contact and recognition, this technique isolates the axillary odor from smoke, fragrances, and other odors which may be present on the subject's body or clothing. The axillary odor remains on the tube for several hours if covered and refrigerated. The effects of dl-alpha-tocopheryl acetate on ultraviolet light-induced epidermal ornithine decarboxylase activity Peter T. Pugliese, M.D., Gery B. Saylor, David C. Salter, D. Phil., and Carl Nocka, Ph.D., Xienta, Inc., P.O. Box 98, Bernville, PA 19506 Ornithine decarboxylase (DOC) activity increases in response to ultraviolet (UV) light irradiation. Applying Vitamin E (dl-alpha-tocopheryl acetate) prior to UV irradiation produces a 92% reduction in induced-ODC activity. Our mathematical model predicts that this reduction is due to both a physical blocking of the UV light and a biochemical effect within the epidermis. Vitamin E can be an effective blocking agent if incorporated into a sunscreen, and may also prevent damage caused by the UV light which reaches the stratum comeurn. Finding a preservative system suitable for aloe vera gel Max Ceballos, Aloe Laboratories of Texas, Inc., 2809 E. Grimes, Harlingen, TX 78550 The '*ideal" preservative system for aloe vera gel consists of two components: physical heat and chemicals. The effect of different temperatures with time was examined for aloe vera gel in terms of pH, color, enzyme activity, and bacterial counts. The most lethal temperature was 90øC for 15 minutes, provided a stabilizing agent such as citric acid has been added. The "contact" power and long-range effects of twenty-five different preserva- tives on "raw" aloe vera gel and pasteurized gel were evaluated over a 7 day period. The results indicate these preservatives are geared to gram negative organisms, since they are very ineffective against total counts and, in particular, molds and yeast. Since most of these preservatives are pur- ported to be broad spectrum, these results are surprising. The preservative with the best general performance was diazolidinyl urea + methyl - and propyl - paraben and propylene glycol (Ger- maben II). Release of zinc pyrithione from shampoo bases and the effect of various additives Almas Babar, Ph.D., Christina Kawilarong, and Fotios M. Plakogiannis, Ph.D., Arnold & Marie Schwartz College of Pharmacy and Health Sciences/L.I.U., 75 DeKalb Avenue, Brooklyn, NY 11201 Based on previous work on the use of ZNPT in shampoos, it was demonstrated that its antidan- druff activity greatly depends upon the release rate of the ZNPT from the shampoo base. Therefore a series of ZNPT shampoos were prepared contain- ing several additives: alcohol (95%) 5, 10, and 15% DMSO 5, 10, and 15% PEG-400 5, 10, and 15% and urea 5, 10, and 15%. The release rates from these shampoos were determined at time intervals of 15, 30, and 45 min., and compared with a control shampoo and two commercial products. It was found that the release rate decreased in the follow- ing order: alcohol (95%) propylene glycol DMSO, uvea PEG-400 control commercial products. The data also demonstrated that the release rate was influenced by the percentage of the additive present in the formulation and the time of

402 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS determination of each release rate. Several other tions as to the selection of these silicone copoly- differences and similarities will be discussed. mers for cosmetic formulations will be discussed. Xanthan gum and its role in personal care products Tashie D. Zang, Kelco, Inc., 8355 Aero Drive, P.O. Box 23076, San Diego, CA 92123 Xanthan gum is the high molecular weight, extra- cellular polysaccharide from Xanthomonas campes- tris. Solutions containing xanthan gum have high viscosities at low gum concentrations, are highly pseudoplastic, and possess a yield value. They also show viscosity which is highly stable in the pres- ence of salt and over wide ranges of pH and temperature. In addition, xanthan gum is compati- ble with many formulation ingredients, such as acids, bases, reducing agents, salts, solvents, enzymes, surfactants, preservatives, and other thick- eners. Some of the benefits provided by xanthan gum in personal care products are (a) good emulsion stabil- ity (b) low viscosity under shear, which allows ease of application (c) excellent suspension of particu- late solids, which is most useful in highly pig- mented products as well as some medicated prod- ucts (d) enhanced foam stability, an important feature in liquid shampoos and liquid soaps (e) good skin feel (f) no "bailing up" of the product on application (g) improved viscosity stability and uniformity with temperature change. Structure/property relationships for silicone polyalkyleneoxide copolymers and their ef- fects on performance in cosmetics M. L. Gum, Ph.D., and S.C. Vick, Ph.D., Union Carbide Corp., Old Saw Mill River Road, Tarry- town, NY 10591 High performance, silicone based wetting agents, commonly referred to as silicone polyalkyleneoxide copolyols, are frequently used in the personal care and cosmetic industries. The unique, highly designed structures of commercially available sili- cone polyalkyleneoxide copolymers impart proper- ties desirable to the cosmetic formulator. These versatile additives find utility as emulsifiers, moisture barriers, flow control and leveling agents, softeners, dispersants, lubricants, potential wetting agents, etc. Utilizing model compounds, the effects of structural changes (such as molecular weight, degree of organomodification, silicone/poly- alkyleneoxide balance, or type of polyether side chain) on the various wetting properties were assessed. Differences in surface tension lowering, cloud point, wet out times, and foam heights were related to structural modifications. Some sugges- Free amino acids of stratum corneum as a biochemical marker to evaluate dry skin J. Koyama, I. Horii, K. Kawasaki, Y. Nakayama, Y. Morikawa, and T. Mitsui, Ph.D., Shiseido Labora- tories, 1050 Nippa-cho, Kohoku-ku, Yokohama, Japan 223 Free amino acids of stratum corneum were studied by using simple extracts from facial skin surface of female subjects. The composition of free amino acids obtained from dry and flaky skin (dry skin) was significantly different from those of normal skin, in which citrulline, alanine, pyroildone carboxylic acid, and urocanic acid decreased, and their precursor amino acids increased. These changes were found to be similar to those observed in hyperkeratonic skin induced by an application of detergent. Our previous findings indicated that free amino acids and their metabolites from stratum corneum are produced via degradation of certain epidermal proteins and further metabolization during the final stage of the keratinizing process. These results suggest that the hyperproliferative alteration of epidermis is involved in dry skin during winter months. The present study indicates that the analysis of free amino acids extracted from skin surface will provide a non-invasive biochemi- cal method for evaluating dry skin conditions. Organoclays in cosmetics Thomas W. Powell, Jr., Clays and Minerals Divi- sion, United Catalysts Inc., P.O. Box 32370, Louis- ville, KY 40232 The function of organoclay in cosmetics will be described in detail, as well as the mechanism of gel formation. The effect of the solvency of various organic fluids on gel properties will also be dis- cussed. The important role of moisture in gel formation will be stressed, with nail lacquer systems as an example. Practical hints for quality control of organoclays will be given that can directly relate to product performance, such as suspension of active materials in antiperspirants. Electron micrographs of various organoclay materials help visualize per- formance properties. Utilizing these concepts, the cosmetic formulator should be better able to pre- dict how organoclay products will perform in a given system and how to solve production prob- lems with organoclays.