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.
All peptides are sent directly to the customer by FedEx overnight delivery from our Sunnyvale, California headquarters. An email is sent to the end-user the day of the shipment confirming the shipping and including a FedEx number so they can trace the box if necessary. Each peptide is supplied at room temperature with a desiccant to remove any extra moisture. Numerous studies have shown that transporting peptides under these circumstances has no effect on their viability or shelf-life. However, the generic peptides must be kept at -20 C or lower as soon as the end customer receives it.
Peptides must be warmed to Romm temperature before being opened since they are hygroscopic. The most effective technique to prevent water condensation from accumulating on the peptide is to warm in a desiccator or dry box. During peptide manufacturing, it is crucial to minimize contamination. This can be achieved by weighing out the product in a sterile atmosphere, ensuring only the required amount is used. Afterward, the containers must be resealed carefully. Any unused peptide should be stored in a sealed container with a desiccant, preferably at a temperature of -20°C or lower. By adhering to these storage conditions, bacterial breakdown, the formation of secondary structures, and oxidation can be significantly reduced or even halted for several years. Cysteine, methionine, tryptophan, asparagine, glutamine, and N-terminal glutamic acid-containing sequences will degrade more quickly than other peptides. If your experimental setup permits it, please utilize the suggested solvents listed in the solubility test that CPC provides for solubilizing the peptide. The GMP peptide can often be broken down by sonication. In general, sterile water is the best solvent, although depending on the peptide's amino acid sequence, acidic peptides will dissolve in a basic buffer and basic peptides in an acidic buffer. Since they are particularly prone to oxidation, Cys, Met, and Trp-containing peptide sequences demand oxygen-free solvents. The stability and shelf life of peptides in solution are significantly lower than those in lyophilized form. In order to increase shelf life, peptides in solution should be stored at -20 C using sterile buffers with a pH of 5–6 rather than under these conditions, which is not advised. Having CPC aliquot the peptide is the best method to steer clear of this problem.