Theoretical net peptide content (calculated assuming that counterions are the only non-peptide components present in your peptide sample) can be estimated by dividing molecular weight of the peptide by a sum of this molecular weight and a number of trifluoroacetate counterions that are required to neutralize the peptide multiplied by the molecular weight of the TFA counterion (MW= 114). For example, a synthetic peptide of MW=1000 with a free N-terminal amino group and one Arg has theoretical net peptide content of 1000/(1000 + 2 x 114 ) = 1000/1228 =0.81 or 81%. In practice, counterions are not the only possible contaminants in the peptide sample. It can also contain water, absorbed solvents and traces of other substances. As a result, the actual net peptide content is usually determined by quantitative amino acid analysis.
Articles in this section
- Why it is difficult to synthesize peptide with FITC without the Ahx linker?
- I also noticed that one of the peptides was pinkish and others yellow.Could you please let me know the reasons?
- What’s the condition you suggest to store the peptide powder and the solution? Also, how long can they be store at room temperature?
- How to read my peptide QC report? Especially the HPLC and MS report?
- I would like to know what quality control measure you employ i.e., how do I determine that the product you sent me is what I wanted?
- How many continuous "R" can we synthesize in a peptide?
- Do you provide peptoid service?
- Can you cyclize my peptide by disulphide bond (cysteine bridge) while my peptide sequence contains 3 cysteines?
- What is your recommended peptide purity for in vivo application?
- For the peptide synthesis, can you send me the synthesis protocol that was used including the procedure that was used for making the disulfide bonds?