Do I need to use fresh yolks?
Eggs stored in the refrigerator for up to two months may be used or yolks can be processed and stored frozen.
Do I need to change the protocol when using frozen eggs?
To store yolks frozen before purification, mix them well with cold Delipidation Reagent (two times the original yolk volume), and store them for approximately one year.
Why do I need to use cold eggs?
Delipidation occurs optimally at 4°C, so it is best to have eggs and reagents cold.
How much IgY can be purified with this kit?
The kits can purify up to 100 mg of chicken IgY per yolk (i.e., 500 mg with #44918 and 2,500 mg with #44922).
How should I store the purified IgY?
Store the purified IgY at 0-4°C (< 6 months). For longer storage, separate the IgY into small volumes, add a small amount of glycerol (< 10%) to help stabilize the IgY and store at -20°C.
What is the molecular weight of IgY?
IgY has a mass of 180kDa, which is more than IgG because the IgY heavy chain has an extra domain on the Fc region. The light chains are ~22 kDa and the heavy chains are ~68 kDa; however, estimates vary in the literature.
Can I immobilize IgY on Protein A, Protein G or Protein A/G to immunoprecipitate or affinity purify the antigen?
No. IgY does not bind to Protein A, Protein G or Protein A/G; however, AminoLink Plus Resin (#20501) or Kit (#44894) can immobilize IgY. The AminoLink Plus Resin is aldehyde-activated and reacts with primary amines on the IgY and forms a covalent linkage.
Is there any difference between IgY from serum versus egg yolks?
No. Serum and egg IgY are the same. The advantage of collecting IgY from the yolks is the high concentration of IgY per yolk versus IgY in serum.