Abstract
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 abdominal
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 partitioning
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