Page 391 - Tandem Techniques
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Figure 9.33
The MS/MS Spectra from a Mass
Separation of a Mixture of Peptides.
Reprinted with permission from M. Wilm and M. Mann, Anal.
Chem., 68(1)(1996)1, Copyright 1996 American Chemical Society
Post Column Additives in LC/MS using Electrospray Interfaces
A technique using on-line post-column adduct formation in an electrospray interface was developed by
Kohler and Leary [29] for the analysis of carbohydrate mixtures. A tri-axial electrospray probe was
designed, very similar to that described in Figure 9.31, that would allow the introduction of the eluent,
the nebulizing gas and a metal chloride reagent solution simultaneously into the probe jet.
Two LC pumps provided gradient elution facilities and the sample was placed on the column with a low
dispersion sample valve, having a 5 µl loop. After injection, the sample contained in the mobile phase
passed through a 0.5 µm filter onto the column. The column was the Spherisorb s5-NH2 microbore
column, 25 cm long and 1 mm I.D., operated at a flow rate of 20 µl/min. The center tube (see Figure
9.31 carried the column
