Construction and optimization of a capillary electrophoresis electrospray ionization time-of-flight mass spectrometer.

摘要

High efficiency separation methods such as capillary electrophoresis (CE) interfaced with structural information-producing detection systems such as mass spectrometry (MS) represent invaluable tools in analytical chemistry. In order to extend the analytical power of CE, new detectors which demonstrate increased speed, sensitivity, and specificity must be developed. In this dissertation, the design, construction, and optimization of an electrospray ionization (ESI) time-of-flight mass spectrometer (TOFMS) and its performance as a detector for CE is described. The major contributing factors to high quality analysis, characteristic of each separate technique, are considered, relevant examples are discussed, and fast, sensitive analysis is demonstrated. Emphasis is placed on fulfillment of the speed and sensitivity requirements. Spectra can be acquired at rates as high as 10,000 Hz, eliminating problems with loss of information due to limitations in the data acquisition rate. Low attomole (3-11) and low femtomole (1-10) detection limits are demonstrated for continuous infusion and CE-MS operation, respectively.