title: Long-lived metallized tips for nanoliter electrospray mass spectrometry.
abstract: Sheathless electrospray at nL/min flow rates combined with Fourier-transform mass spectrometry has made possible high resolving power (>50,000) mass spectra of subattomole samples of >8 kDa proteins separated by capillary electrophoresis (Valaskovic, G. A.; Kelleher, N. L.; McLafferty, F. W. Science, 1996, 273, 1199-1202). However, for this new method the mechanical stability of the thin (35 to 100 nm) gold film electrodes has limited tip lifetime to 15 to 30 min. A technique for SiO x coating of the gold is described that provides a steady ion current (±10 pA) for 1 to 2 h, even with arcs or interruptions of the electrospray voltage.
authors.affiliation: Chemistry Department, Cornell University, Ithaca, New York, USA.
authors.forename: G A
authors.initials: GA
authors.lastname: Valaskovic
authors.forename: F W
authors.initials: FW
authors.lastname: McLafferty