POLOXAMER 407 GEL FOR TOPICAL ADMINISTRATION: INFLUENCE OF ACETIC ACID AND DEMINERALIZED WATER ON THE BEHAVIOR OF THE GEL OBTAINED

Background: Poloxamers are low-toxicity copolymers whose aqueous solutions can pass reversibly from the ground state to the gel state at temperatures approaching body temperature, which is of interest for their use as a reservoir system of active principle. Understand the effect of the type of solvent on the rheological characteristics of the gel obtained. Methods: Various formulations of Poloxamer 407 gel at 16% and 17,5% were prepared and evaluated successively in acetic acid and demineralised water. The main evaluation parameters were the gelling temperature (T gel) and the concentration of these different solvents. Results: The T (gel) at 16% F127 in demineralised water and 0.1M acetic acid was 27º ± 0.3 and 17.5% at 25º to 29ºC ± 0.1. in 0.1M and 16 % acetic acid, there is no marked gelation. At 17.5% F127 in acetic acid, gelationwas observed and the Tgel was higher than with F127 in deionized water. Conclusion: The gelation process is favored by increasing the concentration of F127 and is substantially disadvantaged by 0.1M acetic acid