ROSIN-BASED POLYMER AS CREAM BASE 207 I 7 14 21 •8 35 42 Time(Days) Figure 4. The changes in the relative dielectric constant of the prepared creams during aging. RT: cream with Tween 60. R2: cream with polymer 2. 7OO0 6OO0 •. 5ooo •. 4ooo o 3000 ._• o 2000 1000 i i i i i i i 1 7 14 21 28 35 42 Time (Days) Figure 5. The changes in viscosity of the prepared creams during aging. RT: cream with Tween 60. R2: cream with polymer 2.

208 JOURNAL OF COSMETIC SCIENCE Though the initial viscosity of the cream containing polymer 2 (6400 centipoises) was greater than that of the marketed preparation (6000 centipoises), the overall release pattern of the drug from the cream containing polymer 2 was similar. However, there are similar findings in earlier published literature (15), which has indicated that a gel formulation (containing Carbopol 940 or emulsion base) with higher viscosity showed a better release profile than one with lower viscosity. CONCLUSION On the basis of the release parameters and storage stability, it seems that the cream prepared by using polymer 2 shows a good release pattern and storage stability and that it can be used successfully as hydrophilic cream base. REFERENCES (1) P. Balakrishnan, S.S. Sangole and B. B. Gogte, Pa/nt/nd/a, 44, 37 (1994). (2) B. N. Mundhe, S. P. Morey, and B. B. Gogte, Paint/ndi•, 44, 77 (1993). (3) G. Melin, Antiwrinkle beauty cream composition, Fr. Demande FR 2,693,371, Chem. Abs., 120, (1994). (4) D. S. Sheorey and A. K. Dorle, J. Microencapsulation, 11, 11 (1994). (5) Y. V. Pathak, R. L. Nikore, and A. K. Dorle, Int. J. Pharm. 24, 351 (1985). (6) Y. V. Pathak, and A. K. Dorle, IndianJ. Pharm. Sci., 48, 16 (1986). (7) P.Y. Klyuev, A.Y. Klyuev, I.V. Antonovich, A.K. Strakh, and O.A. Novikov, U.S.S.R. SU 1810368 A1, April 23, 1993. (8) S. Icli, F. Uysal, Turk. J. Chem., 16, 307-314 (1992). (9) C. W. Chien, J. Am. Chem. Soc., 62, 4762 (1960). (10) Y. V. Pathak, R. L. Nikore, and A. K. Dorle, Int. J. Pharm., 24, 351 (1985). (11) Nakagava et aL, U.S. Patent, 5,478,567, December 26, 1995. (12) Oda et al., U.S. Patent, 5,725,874, March 10, 1998. (13) N.H. Sahu, P.M. Mandaogade, A.M. Deshmukh, and A. K. Dorle, Biodegradation studies of rosin- glycerol ester derivative, J. Bioactive Compatible Polymers, 14, 344-360 (1999). (14) Y. W. Chien and P. R. Keshary, Drug. Dev. Ind. Pharm., 10, 883 (1984). (15) S. P. Patvardhan, K. S. Joshi, R. V. S. V. Vadlamudi, and S. G. Deshpande, Development and in vitro evaluation of diclofenac hydroxyethyl pyrrolidine formulations containing penetration enhancers, In- dianJ. Pharm. Sci., 61, 7-11 (1999).