Kinetic Studies of Reactions in Solution Using Fast Mass Spectrometry.

摘要

A summary ot three years of work is difficult to reduce to a tew sentences. We have applied Hadamard transform mass spectrometry to stop-flow kinetics and shown how this technique can complement previous stop-flow studies that rely instead on spectroscopic signatures. We have also examined hypergolic reactions. In particular, we performed electrospray ionization mass spectrometry (ESI-MS) and MS/MS fragmentation studies to determine the composition ot a previously unknown precipitate. We discovered that the precipitate consisted of melamine oligomers and polymers. However, the majority ot the effort involved an ambient ionization method that can be carried out at atmospheric pressure at room temperature-- desorption electrospray ionization (DESI). Here charged droplets are fired at some surface and the resulting splash ot smaller droplets enter a mass spectrometer. We applied this technique to show how to overcome adverse effects from salt and detergent in electrokinetic separations using a spinning disk. We also applied this technique, we believe with great success, to study reaction intermediates and to demonstrate the potential of using DESI for mass spectrometric imaging.