The University of Tennessee seeks support to expand the Chemistry Mass Spectrometry (MS) Center by adding a triple quadrupole electrospray (ES) liquid chromatography (LC)/MS system. ES is needed for expanded applications, particularly those involving characterization of biochemical systems. The instrumentation will also be used for fundamental studies of solvation and other chemical factors affecting ES sensitivity; and for investigation of the mechanism of soluble polymer size-selective capillary electrophoresis. Since ES spectra are characterized by multiple charging, the proposed 4,000 mass-to-charge (m/z) range corresponds to a practical mass range well in excess of 105. This constitutes an order-of-magnitude increase relative to current nominal capabilities, and a two order of magnitude practical improvement, in light of the special strengths (including sub-femtomole sensitivity) of ES. The system will accommodate a wide range of chromatographic solvents and flow rates, facilitating work in microscale and conventional analytical separations. The tandem MS capabilities of the instrument will provide structural insight across the full range of analyte compounds, even for individual components of unresolved or partially resolved mixtures.