Scientists have created a molecular communications system for the transmission of messages and data in challenging environments where electromagnetic waves cannot be used — such as tunnels, pipelines, underwater, within the body, and in biomedical nanorobots.  “We believe we have sent the world’s first text message to be transmitted entirely with molecular communication, controlling concentration levels of the alcohol molecules, to encode the alphabets with single spray representing bit 1 and no spray representing the bit 0,” said York doctoral candidate Nariman Farsad, who led the experiment.  More details can be found here:

https://www.kurzweilai.net/worlds-first-text-message-via-molecular-communication-sent