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the SMPR Method
Performance
REquirements table
specifications for all
analytes in the SMPR
applicability statement? If
not, please specify what is
missing and whether or
not the method's
applicability should be
modified.
unclear from the submission which data were used
to generate these values. As noted in previous
questions regarding definitions, the use of whole
milk powder instead of whole liquid milk and spray
dried whole egg instead of liquid whole egg affects
the MQL, MDL, and quantitative range values for
method performance in some cases. Also, as
discussed in the summary and in later questions,
there are issues around the clarity of the
quantification strategy, which also impacts the
method the authors used to determine Recovery
performance.
1. Based on the
supporting information,
were there any additional
steps in the evaluation of
the method that indicated
the need for any
additional precautionary
statements in the
method?
No.
2. Is there information
demonstrating that the
method system suitability
tests and controls as
specified in the SMPR
worked appropriately and
as expected? If no, please
specify.
The choice of materials for the system suitability
test (fractionated or partially purified versions of
proteins from two foods) seems a bit unusual and
requires more justification. Also, the levels at which
these suitability samples were run does not
correspond to the SMPR, which requires blank
check samples and check standards at the lowest
point and midrange point of the analytical range.
Also, it’s unclear even how the given peptide peak
areas would be obtained for
Milk.Protein_2.Peptide_B, as this peptide is from
beta-casein (see description in general comments),
which is not specifically included in the system
suitability test sample.
3. Based on the
supporting information, is
the method written clearly
No. One of the primary issues is with the
quantification strategy. It is unclear from the
submission how quantification would be conducted