A 1972 paper in the journal Science proposed a model for electronic conduction in the melanins. Historically, melanin is another name for the various oxidized polyacetylene, polyaniline, and Polypyrrole "blacks" and their mixed copolymers, all commonly-used in present day organic electronic devices. E.g., some fungal melanins are pure polyacetylene. This model drew upon the theories of Neville Mott and others on conduction in disordered materials. Subsequently, in 1974, the same workers at the Physics Department of The University of Texas M. D. Anderson Cancer Center reported an organic electronic device, a voltage-controlled switch
Their material also incidentally demonstrated "negative differential resistance", now a hall-mark of such materials. A contemporary news article in the journal Nature noted this materials "strikingly high conductivity'. These researchers further patented batteries, etc. using organic semiconductive materials. Their original "gadget" is now in the Smithsonian's collection of early electronic devices.
This work, like that the decade-earlier report of high-conductivity in a polypyrrole, was "too early" and went unrecognized outside of pigment cell research until recently. At the time, few except cancer research institutes were interested in the electronic properties of such polymers, which are applicable to the treatment of melanoma.
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