Single Silver Ions Facilitate Intramolecular Hydrogen Atom Transfer and C-C Bond Dissociation of Neurotransmitters
Tryptophan(Trp),tyrosine(Tyr),and histidine(His),known as three essential amino acids,are also pre-cursors of vital neurotransmitters in brain nutrient metabolism.In this study,we have conducted a gas-phase study on their interactions with silver ions by a customized re-flectron time-of-flight mass spectrometer combined with a magnetron sputtering source and a downstream flow tube reactor.It is unveiled that these physiological molecules are readily dis-sociated in the presence of Ag+ions,giving rise to fragmentation and recombination prod-ucts.Utilizing density functional theory calculations,we have clarified the reaction mecha-nism of the dissociative process.It is found that the silver ions facilitate the hydrogen atom transfer reaction followed by competitive Cα-Cβ and Cβ-Cγ bond dissociation.This study en-riches the basic and precise properties of such neurotransmitter molecules and helps us under-stand similar physiological mechanisms in vivo.