title: Attomole-sensitivity electrospray source for large-molecule mass spectrometry.
abstract: Full mass spectra of high resolving power are obtained from 0.2 nL sample volumes of large (> 10 kDa) nucleotides and proteins using a new electrospray ionization (ESI) system combined with Fourier transform mass spectrometry. The ESI needles are fabricated by laser-heated pulling of fused-silica tubing (5-20 microns i.d.), followed by chemical etching and surface metalization. Total analyte loaded at the instrument of 8.6 fmol and 216 amol produces signal-to-noise ratios of 400:1 and 60:1, respectively, and resolving power of > 10(5) for full mass spectra, while the total amount of material consumed is approximately 150 and 10 amol, respectively.
authors.affiliation: Baker Chemistry Laboratory, Cornell University, Ithaca, New York 14853-1301, USA.
authors.forename: G A
authors.initials: GA
authors.lastname: Valaskovic
authors.forename: N L
authors.initials: NL
authors.lastname: Kelleher
authors.forename: D P
authors.initials: DP
authors.lastname: Little
authors.forename: D J
authors.initials: DJ
authors.lastname: Aaserud
authors.forename: F W
authors.initials: FW
authors.lastname: McLafferty
mesh_terms: D000818:Animals; D002417:Cattle; D003574:Cytochrome c Group / Q000032:analysis* / Q000737:chemistry; D004247:DNA / Q000032:analysis* / Q000737:chemistry; D005583:Fourier Analysis; D006736:Horses; D007834:Lasers; D013058:Mass Spectrometry; D008970:Molecular Weight; D014452:Ubiquitins / Q000032:analysis* / Q000737:chemistry
chemical_list: D003574:Cytochrome c Group; D014452:Ubiquitins; D004247:DNA