AN AUTOMATED ELECTROOSMOTIC SAMPLE INTRODUCTION SEPARATION INTERFACE FOR AUTOMATED ELECTROOSMOTIC FLOW FLOW-INJECTION MASS-SPECTROMETRY, INFUSION MASS-SPECTROMETRY AND CAPILLARY ELECTROCHROMATOGRAPHY MASS-SPECTROMETRY/

A novel automated electro-osmotic flow (EOF) sample introduction and s eparation interface has been designed, developed and successfully coup led to an electrospray mass spectrometer, The system consists of a sma ll-footprint automated capillary electrochromatography (CEC) injection and separation interface that has an integrated autosampler and conne cts to the outside world via a proprietary controller for automated CE C/MS, EOF infusion and flow-injection analysis (EOFFIA). The system ut ilizes a previously described CEC/MS/MS micro-electrospray interface t hat allows optimization of the spray conditions. Short CEC columns or open capillaries are immobilized in a hollow stainless steel needle th at is located in a pincher bar through which injection and running hig h voltage is applied. The needle assembly is easily removed for ease o f column installation and changeover. At the heart of the automated sy stem is a microprocessos-based controller which allows both manual and automated control via a 12-way key pad,The controller provides automa tic indexing of a 10 position sample carousel, control of kV supply so that injection and running voltages can be set independently for full flexibility and mass spectometer synchronizing signals. The design, a lthough currently on a Finnigan TSQ 7000, has been made flexible in bo th mechanical and electronic design to be easiliy adaptable to other m ass spectrometers. Examples of all functions of the system are present ed here including rapid how injection and controllable infusion experi ments. Simple mixtures could be separated by CEC/MS with great efficie ncy and sensitivity in a short time. An example of multiple automated analytical runs performed continuously over a period of 10 hours are d escribed. We believe this is the first report of a custom built CEC sy stem with an integrated CEC/MS/MS interface that obviates the need for an expensive and unsuitable converted commercial CE system for sample introduction whilst allowing for a useful degree of automation. This system addresses many of the robustness and reduction-to-practice prob lems of CEC/MS and will catalyse the development of CEC/MS and allow t he systematic optimization and evaluation of the technique. (C) 1998 J ohn Wiley & Sons, Ltd.