In the nature, living cells can move preferentially in the direction of the higher concentration of certain chemical and such movement is called as „chemotaxis". In present paper we focus on the study of Artificial chemotaxis" of synthetic objects without any sign of life. Oil droplets consisting of pure decanol are able to move in a gradient of salt in a water solution containing sodium decanoate. We evaluated key parameters of the chemotactic response, namely the induction time and the migration velocity as function of the sodium decanoate concentration and the salt concentration gradient. We have found that this artificial chemotaxis system bears many qualitative similarities with natural chemotaxis systems, namely: (i) the ability to perform chemotaxis repeatedly when the chemoattractant gradients are re-created; (ii) to perform chemotaxis in topologically complex environments (e.g. mazes); (iii) to select the chemotaxis direction based on the relative strength of alternative chemoattractant sources; (iv) to wait in a dormant state and later respond to a stimuli-responsive chemoattractant release; and finally, (v) to deliver a reactive payload towards the chemoattractant source. To the best of our knowledge, this is the first time that an artificial chemotaxis system exhibiting all of the above-mentioned five features has been described.
jitka.cejkova@vscht.cz
