protonin

Protonin is a term that does not correspond to a widely recognized real substance in mainstream chemical literature. In some speculative or educational contexts, protonin is used to denote a hypothetical organic molecule proposed as a model proton carrier or transporter to illustrate proton transfer.

In theoretical discussions, protonin is described as a small organic molecule with an acidic site capable of donating a proton and a basic site that can accept one, allowing intramolecular proton transfer. No canonical structure exists, and proposed forms vary. Depending on the environment, simulated protonins are treated as zwitterionic or neutral, with properties that favor proton shuttling under aqueous or membrane-like conditions.

Applications of the concept are primarily pedagogical, aiding explanations of proton conduction, hydrogen-bond networks, and related mechanisms such as the Grotthuss mechanism. Some models explore how protonin-like motifs could participate in proton-coupled transport within biological membranes or synthetic ion-conducting systems.

Etymology: the name is formed from the word proton and the common chemical suffix -in.

See also: proton transport, Grotthuss mechanism, zwitterion, proton pump, proton wire.