Appeal No. 95-2726
Application 07/994,477
appeal and reads as follows:
1. A method of analyzing a protein comprising the steps
of:
(1) adding trypsin to said protein to form a liquid phase
mixture of trypsin and said protein;
(2) optionally reducing the disulfide linkages and
alkylating the resulting sulfhydryl groups of said protein
either before or after said step (1);
(3) allowing the trypsin to digest said protein long
enough to cleave said protein into tryptic fragments of less
than 4000 daltons in said liquid phase;
(4) ionizing a portion of the digested mixture by ion
evaporation to produce gas phase ions of said tryptic
fragments from said liquid phase, said gas phase ions being
predominantly doubly charged with one charge at each end of
said double charged ions,
(5) and analyzing said gas phase ions of said tryptic
fragments by sequentially selecting therefrom doubly charged
ions in a first mass analyzer, fragmenting such selected ions
by collision in a second mass analyzer to produce daughter
ions, and then analyzing said daughter ions in a third mass
analyzer.
The references relied on by the examiner are:
Henion et al. (Henion) 4,861,988 Aug. 29, 1989
(filed Sept. 30, 1987)
Yost et al. (Yost), “Triple Quadrupole Mass Spectrometry for
Direct Mixture Analysis and Structure Elucidation,”
Anal. Chem., vol. 51, pp. 1251A-1264A (1979).
Vestal, “High-Performance Liquid Chromatography-Mass
Spectrometry,” Science, vol. 226, pp. 275-281 (1984).
2
Page: Previous 1 2 3 4 5 6 7 Next
Last modified: November 3, 2007