A Possible Unitary Mechanism for General Anesthesia

 e oxygen reduction reaction (ORR) is of high importance because of its role in cellular respiration. Recently, a possible relation between respiration and general anesthesia has been found.  is work aims to explore whether anesthesia related gases a ff ect the ORR. In ORR, oxygen which is in its triplet ground state is reduced to form products that are all in the singlet state. While this process is “in principle” forbidden because of spin conservation, it is known that if the electrons transferred in the ORR are spin polarized, the reaction occurs e ffi ciently. Here we show, in electrochemical experiments, that the e ffi ciency of the oxygen reduction is reduced by the presence of general anesthetics in solution. We suggest that a spin-orbit coupling to the anesthetics depolarizes the spins.  is causes both a reduction in reaction e ffi ciency and a change in the reaction products.  e fi ndings may point to a possible relation between ORR e ffi ciency and anesthetic action.  e oxygen reduction reaction (ORR) involves a reduction of oxygen by two pairs of electrons and it depends on the pH. ,  e reaction is of high importance since it is responsible for the cellular 1 2 respiration process and the functioning of fuel cells. In both of these applications, the oxygen, which 3 is in a triplet ground state, reacts to form products that are in their singlet state. As is well established in chemical reactions, when a reagent is in a triplet state, most probably the product will also be a triplet. In the past, this “anomaly” in the

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