A quantitative method for assessing cosmetics for efficacy at reducing wrinkles

This study postulates a quantitative method to assess cosmetics for wrinkle diminution. For this effect, the replica technique and scanning electron microscopy (SEM) were used. The technique used in this study consists essentially of three steps: obtaining a negative skin replica using a mixture of silicone plus a catalyst; obtaining a positive skin replica from the negative replica; and, finally, coating the positive replica with a gold-palladium mixture for further SEM observation and photography. The method was standardized and assessed using a base emulsion. When the effectiveness of the method was validated, a study was done of the potential effect of a sodium salt of 2-pyrollidone-5-carboxilic acid as a wrinkle diminisher. Two creams, only one of them containing the active principle, were applied to a female volunteer group for a certain period. A negative replica was taken before and after each cream application period. The assess-ment parameters used were length and width of a previously selected forearm wrinkle. The results showed that the proposed method can detect variations in the length and width of a previously selected wrinkle and that it can also be effectively used in the assessment of cosmetics used to diminish wrinkles