INTERACTION OF SURFACTANTS AND KERATINS 63 Relative uptake % 300 200 100 (oMC) = (DSS)/2,5 (oMC) --(DSS) (aMC) = 2,5(DS ) \ 5.10 -4 10 -3 2,5.10 -3 10-2 2.10-2 C mole1-1 Figure 24. The relative uptake of SDS on stratum comeurn as a function of concentration from its mixtures with MCG. (Reproduced with permission from reference 10.) Whereas the surface tension was essentially independent of the ratios, and always lower than either of the solutions containing the pure constituents (Figure 23), the deposition of the monocaprylate was found to be highly dependent on the overall concentrations (Figure 24). To date no satisfactory theories have been formulated to explain these phenomena. CONCLUSIONS A review of the published literature reveals that surfactants penetrate into keratinous tissues, affecting their structure and physical and chemical behavior. Some of the changes that are brought about have important consequences as far as tile cosmetic attributes of hair, skin and nails are concerned. REFERENCES (1) C. S. Prottey, "The Molecular Basis of Skin Irritation, Cosmetic Science," M. M. Breuer, Ed., Academic Press: New York, 1978 Vol. 1. (2) J. Steinhardt, G. H. Fuggit and M. Harris, Combination of wool protein with acid and base, J. Res. Nat. Bur. Stand., 30, 123 (1943). (3) M. M. Breuer, Penetration charged molecules into proteinaceous tissues, Soc. Chem. Ind., A4onogr. No. 29, London (1968). (4) J. Steinhardt and j. A. Reynolds, "Multiple Equilibrium in Proteins," Academic Press: New York, (1969). (5) I. M. Klotz and D. L. Hunston, Protein interaction with small molecules, J. Biol. Chem., 250, 3001-3009 (1975). (6) M. Harris, "Handbook of Textile Fibers," Harris Research Laboratory: Washington, D.C., (1954).

64 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS (7) M. Spei, The ordered matrix fact or artifact?, Proceedings 5th International Wool Textile Conference, Aachen, 2, 90-95 (1975). (8) C. Tanford, "The Hydrophobic Effect," John Wiley & Sons: New York, (1973). (9) J. A. Medley, Diffusion of acid ions in keratin, Trans. Faraday Soc., 60, 1010 (1964). (10) J. Poret, (Laboratoire deRecherches Unilever, 8 Impasse de la Monjoie, 93212 La Plaine de St. Denis, France), personal communication. (11) M. Spei and H. Zahn, Low angle X-ray investigations of strained fiber keratins, Monatsh. Chem., 102, 1163-1181 (1971). (12) M. Spei, W. Stein and H. Zahn, The influence of anionic surfactants on the small angle X-ray diffraction of fibrous keratin, Ko/lojd Z., 238, 447-454 (1970). (13) M. Spei, The influence of detergent on low angle X-ray diffraction patterns of keratin, App/. Polym. Symp., No. 18, 659-4')62 (1971). (14) H. Zahn, W. Stein and G. Blankenburg, The effect of surfactants with physical properties of keratin fibers, Fette, Seifen, Anstrichm., 70, 757-760 (1968). (15) G.J. Putterman, N. F. Wolejsza, M. A. Wolfram and K. Laden, The effect of detergents on swelling of stratum corneum,J. Soc. Cosmet. Chem., 28, 521-532 (1977). (16) J. C. Dickinson, The influence of surface active agents on the chemical reactivity of wool, IVoo/Sci. Review, 51, 43-59 (1975). (17) H. Meichelbeck and H. Knittel, The influence of anionic and cationic surfactants on the reactivity of wool, Fette, Seifen, Anstrichm. 73, 25-29 (1973). (18) H. Meichelbeck and H. Knittel, The alkaline degradation of wool in the presence of surfactants, A/lelliand Textilber., 52, 1447-1450 (1971). (19) E. D. Goddard, T. S. Phillips and R. B. Hannah, Water soluble polymer-surfactant interactions--Part I.,J. Soc. Cosmet. Chem., 26, 461-475 (1975). (20) j. A. Faucher, E. D. Goddard and A.M. Kligman, Protection of the skin by a cationic cellulose polymer, Cosmetics and Toiletties, 92, 39-43 (1977). (21) j. c. Griffith and E. E. Alexander, Equilibrium adsorption isotherms of wool-detergent systems, J. Colloid and Interface Science, 25,311-316 (1967).