Experimental Investigations on Hair Fibers as Diffusion Bridges and Opiates as Solutes in Solution

In 1996, researchers Skopp, Pötsch, and Aderjan conducted diffusion experiments using clipped hair fibers and aqueous solutions of morphine, codeine, and dihydrocodeine. They found that when virgin hair samples were used, the solutes passed along the fiber at full length, resulting in a positive immunological finding at the end of the diffusion bridge. Most of the washing fluids were positive for opiates, and all centerpieces had a high opiate content. The opiate concentration in damaged hair was significantly higher. The study concluded that radial swelling of the hair fiber with radial diffusion was the first and main process to appear when hair was exposed to water. The diffusion process in hair could not be placed in a simple mathematical treatment.