When a peptide is reported to be 95% pure, it means that 95% of the material in the sample is the target peptide, while the remaining 5% consists of impurities or related substances. The specific nature of these impurities can vary depending on the synthesis and purification processes, as well as the quality control measures applied. Here are some common impurities that might be present in a peptide sample:
-
Truncated Peptides: These are peptides that are shorter than the full-length target peptide. They can result from incomplete coupling reactions during synthesis.
-
Side-Chain Modifications: Some amino acid residues in the peptide may have undergone unintended side-chain modifications, such as acetylation, amidation, or oxidation.
-
Deletion Sequences: Deletion sequences are missing amino acid residues in the peptide sequence due to incomplete coupling reactions or deletion during synthesis.
-
Epimerization: In some cases, racemization or epimerization may occur, leading to the presence of D-amino acids in the peptide instead of the desired L-amino acids.
-
Salt and Counterions: Small amounts of salts and counterions from reagents or buffers used during synthesis and purification may be present in the sample.
-
Residual Reagents: Residual reagents, such as protecting groups or coupling reagents, may remain in the peptide sample if not completely removed during the purification process.
-
Peptide Aggregates: Peptide aggregates or dimers may form during synthesis or purification, contributing to the impurity.
-
Water and Solvents: Some residual water or organic solvents used during synthesis and purification may be present in the sample.
-
Isomers: Depending on the synthesis process, structural isomers or regioisomers may be present as impurities.
To achieve a higher level of peptide purity, additional purification steps or optimization of the synthesis process may be necessary. The specific impurities and their concentrations in a peptide sample can be determined through analytical techniques, such as high-performance liquid chromatography (HPLC) and mass spectrometry (MS). Understanding the nature and amount of impurities is important for assessing the quality and suitability of the peptide for its intended application.
Website: https://www.ks-vpeptide.com/
