Lithium and sodium ion binding energies of N-acetyl and N-glycyl amino acids

A study investigated the ion affinities of a series of N-acetyl and N-glycyl amino acids using an ion-trap mass spectrometer with an electrospray ionization source. Li+ and Na+ binding energies were determined and gas-phase basicities were measured for each of these compounds which exemplify simple models of amino acids in a peptide chain. Among other results of the study, it was found that the Li+ and Na+ binding energies of these compounds suggest that multidentate chelation plays a significant function in the binding.