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Challenges
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Unique protein and peptide selections with different digestion conditions
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Perform protein ID for allergens: Trypsin; chymotrypsin; species selected based on the
list highlighted by The Codex Alimentarius.
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Search against database and select unique proteins/peptides.
Goal
:
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Detection of two proteins each species (if available), 3‐4 peptides each protein, and 3‐4 MRM
transitions each peptide.
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MRM transition selections with consideration on sensitivity and few/no interferences from
the food matrix.
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MRM transition selections made with consideration of potential modification during food
processing (cooking, baking, fermenting etc. )and storage (i.e. MRMs must be detectable in
raw and processed food)
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Sample clean up: lipids removal
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Try different solvents (ex. hexane, etc)
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Protein extraction and digestion optimization
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Try different denature conditions: (ex. heat, urea, OGS, guanidine).
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Final combined mixture of denature reagent.
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Must be simple for sample preparation and easy to reproduce.