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What is the typical purity percentage of custom peptides?

At LexinPharma, the purity percentage of custom peptides is set by our partner’s specification. Typically, many

researchers choose >95% by reverse-phase High Performance Liquid Chromatography (RP-HPLC or rHPLC). This

means that 95% of the NET PEPTIDE content (but not the total peptide content, see “What is net peptide content?“)

of the lyophilized powder shipped to you is composed of your target peptide. The other 5% of the PEPTIDE material

in your sample is usually composed of the deletion and/or addition sequences that sometimes co-elute with the

target peptide. These deletion and addition sequences are generated during peptide synthesis due to the

inefficiencies of coupling certain amino acids (typically β-branched residues (Ile, Val and Thr) or those with bulky

protecting groups (Arg, Gln, Cys and Asn) are either missing or sometimes duplicated) in some of the synthesized

molecules. Purity is usually determined by reverse-phase HPLC. We have the ability to meet any purity percentage