Interference No. 104,745
(Rebuttal Evidence)" (BX 2117), both of which are critical of Dr. Baldwin's rebuttal reasoning
and conclusions. We need not decide Laiko's motion to suppress the Fenn declaration, because,
as explained below, the insufficiency of Dr. Baldwin's rebuttal testimony is apparent without
considering the Fenn declaration, which therefore will not be considered.
Dr. Baldwin contends that production of an analyte mass spectrum was essential to
proving that bradykinin ions were generated and transported to the LC/MSD instrument, because
[t]he recognized standard in the field of mass spectrometry for verification of a
successful test of an "ionization apparatus for connection to a spectrometer" is the
successful production of an analyte ion mass spectrum. Successful mass spectra
have identifiable patterns of mass peaks. Known analytes such as bradykinin and
CZE peptide standard (as used by Bai and Laiko respectively), are used to test
mass spectrometry ionization apparatus specifically because these peptides have
easily recognized, well known, and well documented spectra with patterns of
mass peaks that readily allow those skilled in the art to determine whether an
experiment is successful or not. Absent any mass spectrum, those of skill in the
art cannot say whether or not analyte ions have been successfully transported to
the spectrometer.
Baldwin Decl. (LX 1074) ¶ 68. (Laiko's emphasis.) No documentary evidence is cited in
support of these assertions. Instead, Dr. Baldwin explains that the differences between the 1061
m/z and 1900 m/z chromatograms fail to establish that bradykinin ions were detected for the
following reasons: (1) "large variations in signal/noise can be encountered when the mass
spectrometer settings are changed by large amounts, such as from 1061 m/z to 1900 m/z,
particularly for a quadrupole mass spectrometer," Baldwin Decl. (LX 1074) ¶ 71; and
(2) "nearby signal spikes may occur with selective ion monitoring and may be inadvertently
introduced into the mass spectrometer, depending upon the specifications and the setting of the
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