Formulation study on retinoic acid gel composed of iota-carrageenan, polyethylene oxide and Emulgen® 408.

In the present study, all-trans retinoic acid (RA) gels formulated with various compositions of polyethylene oxide (Emulgen®) and iota-carrageenan (ι-CG) were prepared and their physicochemical properties were evaluated. The compression energy, which is the work required to compress the product through a fixed distance, increased with increasing amount of ι-CG or Emulgen®. The adhesion energy and displacement decreased with increasing amount of ι-CG or Emulgen® due to the progression of gel formation. From the results of the sensory tests, the properties of RA gels such as adhesiveness, gel strength and spreadability seemed to be adjustable depending on the condition of skin by varying the components of RA gels. Through photostability study, the expiration date and storage conditions of RA gels were determined as "4°C for 28 d with no exposure to light."