Bio-hybrid tactile sensor for the study of the role of mechanoreceptors in human tactile perception

In this paper, the design and fabrication of a bio-hybrid tactile sensor is described. The device is designed to sustain the viability of cell-cultures and biological tissues for sufficient time as to allow experimentation in ordinarily non-ideal conditions. This is achieved by ensuring the cells have sufficient nutrients, oxygen and heat. It has an open configuration and is equipped with a local conductivity sensor which is sensitive to variations in the ion concentrations in the extracellular matrix. This allows secondary messengers in the form of the ion output from the cells to be monitored whilst contact stresses are applied to the tissue surface. Initial experiments are also described whereby the local conductivity sensor is submerged in solutions of various concentrations of different salts commonly found in mammalian cells. The sensor response is modelled analytically using complex mapping which lead to expressions detailing the sensitivity of the sensor. At concentrations found in mammalian cells, it was found that the sensor can detect changes in concentration of potassium chloride in solution as small as 0.25 μM.