Differentially heated capillary for thermal dissociation of noncovalently bound complexes produced by electrospray ionization

Abstract

A heated capillary consisting of two independently heated segments is used to dissociate gas-phase complexes of peptides and β-cyclodextrin. By fixing the temperature in the first segment and varying it in the second segment, the complex is first desolvated and then dissociated. The results indicate that the complex is dissociated in the gas phase rather than in the solution phase of an intact droplet. The thermal dissociation profile, the dissociation temperature and apparent Arrhenius parameters E a and A are obtained. These values are compared to E a obtained from blackbody infrared radiation dissociation.