September 27, 2015 SPSFAM Meeting - Meeting Book

Challenges • ELISA kits oftentimes are used by technicians who are not experienced  at LC/MS/MS.

• Allergens are present in many matrices.

• Method development to determine allergen proteins is time  consuming.

• Most food testing labs are used to using LC/MS/MS for small molecule  contaminant testing.

• Sample preparation for allergens (protein digestion) is significantly  different from current sample prep methods (LLE, QuEChERS, SPE, etc)

Challenges

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