Isopropyl myristate, polysorbate 80/water

Ayannides, C.A. and Ktistis, G. (1999) A rheological study on microemulsion gels of isopropyl myristate, polysorbate 80, glycerol and water. /. Cosmet. Sci., 50, 1. 

Lecithin-based o/w MEs for parenteral use were formulated using polysorbate 80, IPM (Isopropyl myristate), lecithin, and water at different lecithin-polysorbate 80 weight ratios [115]. The formulated systems were shown to be highly stable and of minimal toxicity when evaluated in vitro. Phospholipid-based ME formulations of all-trans retinoic acid (ATRA) for parenteral administration were prepared and tested in vitro [116]. ATRA is effective against acute promyelocytic leukemia with highly variable oral bioavailability. Parenteral ME of ATRA was prepared using pharmaceutically acceptable ingredients, namely phospholipids and soybean oil. The inhibitory effect of ATRA on two human cancer cell lines (HL-60 and MCF-7) was not affected by incorporation into a ME formulation. 

Other aspects of formulation such as the nature of the binary or ternary vehicle (oil-surfactant, water-surfactant or oil-water-surfactant, respectively) have been considered recently [151], Addition of polysorbate 80 to the aqueous phase has no significant effect on the epidermal transport of ethanol, but a significant reduction in the transport of the less soluble octanol results, in line with the arguments presented above in isopropyl myristate, octanol transport is not affected by the solubilizer while that of ethanol is decreased. In the ternary systems identified in Fig. 7.35, the results in Table 7.14 were obtained indicating a general decrease in permeability constants for ethanol, butanol and octanol. The viscosity of the vehicles was not a factor although this varied from 1 to 39 X 10 cP. In the ternary systems a surfactant will distribute itself between the aqueous and non-aqueous phase quantitative prediction of permeation is made difficult even with data on the transport properties of the permeants in the individual phase. The results indicate that the percutaneous absorption of the... 

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