THE STRATUM CORNEUM 257 matrix structure and, hence, decrease the possibility of multilayer formation. It is also expected that the diffusion of water vapor molecules would be faster in such a modified structure. This is evidenced by the diffusion coefficient-concentration relationship, -- shown in Fig. 8 as the intrinsic diffusion coefficient Di and mean diffusion coefficient D against percentage water vapor uptake. An average increase of an order of magnitude in the value of D is observed as a result of the solvent treatment. Compare Fig. 9 which shows data for the untreated comeurn. The effect of treatment was also assessed with the help of SEM. Figure 10 (1) and (2) provide a comparison between intact (untreated) and treated guinea pig comeurn. The effects of the organic solvent treat- ment are quite apparent in (2), as judged by the extent of cleavage and disruption of the cellular matrix. "- REFERENCES .: (1) I. Blank, J. Invest. Dermatol., 18, 433 (1952). :: (2) B. Idson, J. Soc. Cosmet. Chem., 24, 197 (1973). . •:. (3) J. Mtddleton, Brit. J. Dermatol., 80, 437 (1968). .:•:• (4) E. Singer and L. Vinson, Proc. Sci. Sect. Toilet Goods Ass., 46, 29 (1966). (5) R. Wildnauer et al., "Applied Chemistry at Protein Interfaces," in Advances Jn Chemistry Series Number ß ::': 145, R. Baler, Ed., p. 74, 1975. (6) A. EI-Shimt and H. Princen, Water vapor sorption and desorption behavior of some keratins, ..:'' to appear in Colloid Polym. Sci. (7) A. EI-Shimi and H. Princen, Diffusion characteristics of water vapor in some keratins, to appear in Colloid Polym. Sci. ß :11. (8) R. Scheuplein and I. Blank, Phys•ol. Rev., 51,702 (1971). ' ::': (9) R. Tregear, Physical Functions of Skin, Academic Press, New York, 1966. .:::::• (10) G. King and A. Cassie, Trans. Faraday Sot., 36, 445 (1940). (11) I. Blanket al., J Invest. Dermatol., 49,582 (1967). (12) R. Scheuplein and L. Ross, J. Soc. Cosmet. Chem, 21,853 (1970). ., i'.':. (13) A. Kligman and E. Christophers, Arch. Dermatol., 88, 70 (1963). ".":.:• (14) A. EloShimi, H. Princen and D. Risi, "Applied Chemistry at Protein Interfaces," in Advances in Chemistry Series Number 145, R. Baler, Ed., p. 125, 1975. i: (15) A. E1-Shimi and E. D. Goddard, J. Colloid. Interfac. Sci., 48,241 (1974). :: .... (16) R. D'Arcy and I. Watt, Trans, Faraday Sot., 66, 1236 (1970). i: :' (17) B. Zimm, J. Chem. Phys., 21,934(1953). (18) J. Crank, Mathematics of Diffusion, Oxford University, England, 1950. ß ....