136 JOURNAL OF COSMETIC SCIENCE know the exact composition of the shampoo or the concentrations of the ingredients in the commercial shampoo. The commercial shampoo also contains other ancillary ingre- dients that we have excluded in our simple model formula. The data for the commercial shampoo is provided in Figure 3. From this data, we note that the relative amount of silicone deposited from the shampoo and the amount of deposition we noted from our model shampoo containing 0.3% cationic polymer are essentially identical, even after multiple washing steps (compare Formulation B and the labeled "2-in-1" shampoo). We feel comfortable, therefore, in suggesting that the use of x-ray fluorescence in the fashion we have described can be predictive of real-world shampoo use. CONCLUSIONS We have demonstrated that x-ray fluorescent spectroscopy can be a useful tool for analyzing the behavior of ingredients delivered from emulsified surfactant systems. While we have focused in this study on the deposition of silicone oil onto hair, and have examined the role dissolved cationic polymers can play in potentiating the deposition, it seems very likely that this technique can be expanded to a wide variety of colloidal systems including, perhaps, the study of antidandruff agents (e.g., pyrithione zinc) and physical sun screens such as TiO 2. Likewise, while we conducted our studies on hair tresses that are readily available, there does not appear to be any reason why this technique could not work on other types of fibers, or membranes such as skin. REFERENCES (8) (9) (10) (1) M.D. Berthiaume, "Silicones in Cosmetics," in Principles of Polymer Science and Technology in Cosmetics and Personal Care, E.D. Goddard and J. V. Gruber, Eds. (Marcel Dekker, New York, 1999), pp. 275-324. (2) E. D. Goddard, "Measuring and Interpreting Polycation Adsorption," in Principles of Polymer Science and Technology in Cosmetics and Personal Care, E. D. Goddard and J. V. Gruber, Eds. (Marcel Dekker, New York, 1999), pp. 465-508. (3) E. D. Goddard, "Polymer-Surfactant Interaction. Part II. Polymer and Surfactant of Opposite Charge," in Interactions of Surfactants with Polymers and Proteins, E. D. Goddard and K. P. Anathaphadmanabhan, Eds. (CRC Press, Boca Raton, Florida), pp. 171-201. (4) B. Jonsson, B. Lindman, K. Holmberg, and B. Kronberg, in Surfactants and Polymers in Aqueous Solution (John Wiley & Sons, New York, 1998), pp. 219-244. (5) K. Shirahama, "The Nature of Polymer-Surfactant Interactions," in Polymer-Surfactant Systems, J. C. T. Kwak, Ed. (Marcel Dekker, New York, 1998), pp. 143-191. (6) D. Myers, in Surfaces, Interfaces, and Colloids: Principles and Applications, 2"d ed. (Wiley-VCH, New York, 1999), pp. 344-357. (7) J. V. Gruber, B. R. Lamoureux, N. Joshi, and L. Moral, Influence of cationic polysaccharides on polydimethylsiloxane (PDMS) deposition onto keratin surfaces from a surfactant emulsified system, Colloid Surf B: Biointerfaces, 19, 127-135 (2000). S. B. Torok, J. Labar, M. Schmeling, and R. E. Van Grieken, X-ray spectrometry, Anal. Chem., 70, 495R-517R (1998). A. De Smedt, I. Van Reeth, S. Marchioretto, D. A. Glover, and J. Naud, Measurement of silicone deposited on hair, Cosmet. Toiletr., 112, 39-44 (1997). H. M. Klimisch, "Personal Care Applications," in The Analytical Chemistry of Silicones, A. L. Smith, Ed. (John Wiley & Sons, New York, 1991), pp. 117-132.

j. Cosmet. Sci., 52, 137-154 (March/April 2001) Papers Presented at the 2000 Annual Scientific Meeting (Friday's Program) December 7-8, 2000 New York Hilton New York, NY 137