Still, by itself this interaction still isn't enough. As Karp points out, "If the gecko's feet were too sticky the gecko wouldn't be able to move at all …(but) the surgeon would want to be able to place this adhesive and then not have it move. So, it needs to be very stable." So, Karp says the researchers added a "thin layer of a biodegradable glue to the surface…(that)…significantly enhances the interaction of our adhesive with the tissue surface."
The research team, which included experts on everything from materials to surgery to, of course, gecko feet, is also developing the biodegradable glue. Karp says the glue "gave us the advantage of chemical cross-links with the tissue in addition to the mechanical interlocking that we get from these adhesives."
Karp says they have tested this tape "against intestinal tissue in the laboratory," but are continuing to tweak both the gecko inspired nanoscale features of the tape and the glue to see if they can improve even more on the gecko's tacky little secret.
Among the other experts on the team were surgeons from Massachusetts General Hospital, Draper Laboratories for the nano scale work, and polymer chemists from Massachusetts Institute of Technology for the special glue.
This research was published online in the Proceedings of the National Academy of Sciences Online Early Edition for the week of February 18, 2008 and was funded by The National Institutes of Health, The National Science Foundation and a Charles Stark Draper Laboratory Fellowship.