Page 386 - Tandem Techniques
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order to achieve the desired results. This is typical of the performance of electrospray interfaces.
Figure 9.29
The Effect of Changing the Extraction Voltage
on the Fragmentation Pattern (ref.25)
In the assays the extraction potential was kept between 15 and 17 V. Examples of the chromatograms
obtained by single ion monitoring at different m/z values, for Cloroxacillin and Penicillin G contained
in muscle tissue, are shown in Figure 9.30. It is seen that monitoring at m/z values of 293, 390 and 434
clearly, and almost exclusively, selects the Cloxacillin from the accompanying unresolved substances. It
would also appear that the best signal-to-nose ratio was achieved employing a m/z values of 293 and
434. From the apparent magnitude of the signal-to-noise
