Nuclear Spin Catalysis: From Molecular Liquids to Biomolecular Nanoreactors

Abstract

All chemical reactions obey the law of conservation of spin angular momentum (‘spin’): any reaction is only allowed when the total spin of reactants is identical to the total spin of products. Correspondingly, free-radical reactions in molecular liquids can be accelerated by changing in electron spin of the reactants via magnetic fields of magnetic nuclei, the so-called “magnetic isotope effect” (MIE). In molecular liquids, the magnetic isotope effects have been discovered for a number of magnetic isotopes, among them H–D, ¹³C, ¹⁷O, ²⁹Si, ³³S, ⁷³Ge, ^117,119Sn, ^199,201Hg, and ²³⁵U. Recently MIE has been discovered in living cells. It was revealed that the rate constant of post-radiation recovery of yeast cells is twice higher for the cells enriched with the magnetic ²⁵Mg when compared to the cells with the nonmagnetic ²⁴Mg. Furthermore, it has been revealed that ²⁵Mg essentially accelerates, 2–2.5 times by comparison to the spin-less ²⁴Mg and ²⁶Mg, the reaction of ATP hydrolysis catalyzed by myosin, the enzyme isolated from muscle cells. Although detailed mechanisms of the ability of biomolecular nanoreactors to perceive the nuclear magnetism require further investigations, the recent developments in this new field highlight promising venues for future research of the magnetic isotope effects (‘nuclear spin catalysis’) in molecular liquids and biopolymer nanoreactors with possible application of the stable magnetic isotopes for control over efficiency and reliability of molecular nanoreactors in engineering and biomedicine.