bstract
Objectives The aim of this study was to investigate the in-vitro permeation enhancement effects of the gel and whole-leaf materials of Aloe vera, Aloe marlothii and Aloe ferox using ketoprofen as a marker compound.
Methods The permeation studies were conducted across excised female abdomi- nal skin in Franz diffusion cells, and the delivery of ketoprofen into the stratum corneum-epidermis and epidermis-dermis layers of the skin was investigated using a tape-stripping technique.
Key findings Aloe vera gel showed the highest permeation-enhancing effect on ketoprofen (enhancement ratio or ER = 2.551) when compared with the control group, followed by Aloe marlothii gel (ER = 1.590) and Aloe ferox whole-leaf material (ER = 1.520). Non-linear curve fitting calculations indicated that the drug permeation-enhancing effect of Aloe vera gel can be attributed to an increased parti- tioning of the drug into the skin, while Aloe ferox whole leaf modified the diffusion characteristics of the skin for ketoprofen. The tape stripping results indicated that Aloe marlothii whole leaf delivered the highest concentration of the ketoprofen into the different skin layers.
Conclusions Of the selected aloe species investigated, Aloe vera gel material showed the highest potential as transdermal drug penetration enhancer across human skin.