Conductivity patterning with Physarum polycephalum: natural growth and deflecting

The present work is dedicated to the use of Physarum polycephalum slime mold, an unicellular organism self-adapting, self-repairing and self-repellent, for the realiza-tion of elements for unconventional computational sys-tems. Physarum continuously changes its shape under the influence of different stimuli like attractors (food in the most of cases) and repellents (light, temperature, humid-ity, chemicals), creating optimized networks. Here we in-troduced a new, softer, element able to influence the mo-tion and the shape of Physarum: the DEFLECTOR. Phy-sarum polycephalum, loaded with magnetic particles and placed under a magnetic field, is conditioned in its active zones routing and shape topology networks. Thus, slime mold can be used as particles carrier and, moreover, it is possible to deflect the mold movement and realize chemical composites in defined places what allows to consider Physarum as a simple version of bio-robot. On the other hand, we have realized the idea of creating net-works with the varied conductivity with the slime mold on polyaniline (PANI) substrates. As the result, it was shown that Physarum growth results in the changing of the conductivity state of PANI layers in different ways, providing negative and positive patterning of the sample. The possibility to control mold’s direction with a deflec-tor together with the capability of Physarum to pattern PANI surfaces are the main points of this work. This pa-per opens new possibilities of the development in many fields and areas from the electrical circuit design and the bio-actuators (bio-) robot research, up to the unconven-tional computing and realization of a novel category of polymer-mold-modified. Optical microscope image of Physarum polycephalum: it creates networks of protoplasmic tubes from the starting blob (the yellow part above).