For its clients, CPC offers custom peptide synthesis services, including a very specific pooling service. We have a broad protocol that is highly good in showing the contents of a pool, but we can tailor it to suit the demands of any customer. 20 peptide subpools are first produced. These pools are subjected to MS, which displays each peak for each peptide found in the subpool. The peptides are often sufficiently varied in mass to distinguish each peak clearly. It can be challenging or impossible to tell the difference, though, if the masses of the two peptides are quite similar. A master pool is then formed by combining all of the produced subpools. The master pool is then subjected to MS with the goal of detecting one peak from each distinct subpool. This shows that every subpool, and hence every peptide, is present in the master pool.