From my point of view, there is no fundamental difference. Some practical aspects should be considered:

1. BSA is smaller and the conjugation density can be easily examined by MALDI-TOF MS. For KLH the analysis of the conjugate may more complicated.

2. BSA conjugates usually have a better solubility.

3. Do not spend too much time to think about the carrier. The chosen peptide (structure), its purity, and the linker are much more mission-critical.

If you are looking for a good conjugation protocol, you might consider ours:

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