Peptide Synthesis FAQs
For quotation, who should I contact?
You can email or contact us as below:
Singapore | peptide@axilscientific.com | +65 6775 7318 |
Malaysia and other countries | info@apicalscientific.com or contact our respective sales representative in your region. | info@apicalscientific.com or contact our respective sales representative in your region. |
For quotation, what information do you need?
We need to have your peptide sequences in order to issue quotation. If there is any complexity involved in synthesizing the peptide, difficulty charges will be imposed.
Customers are recommended to fill up our peptide order form and email to our respective customer care department to request quotation directly.
If peptide sequences are not available, we need the minimum information, i.e. number of amino acid (a.a.), purity (in HPLC %), amount of peptide (in mg) and modification (if there is any) to estimate the quotation.
Do you synthesize short sequence peptides?
Yes, we can synthesize short peptides as small as 2 amino acids or named as dipeptides.
Do you synthesize peptides with modification?
We offer a couple of modification to peptide synthesis. They are phosphorylation, biotinylation, cyclization, fluorescein, D Amino Acid and conjugation.
What are the deliverables (eg. reports, etc.)?
- Peptide Synthesis Summary
- HPLC or Mass Spectrometry QC Report
We recommend the following levels of peptide purity for various applications as below.
Percentage of Purity | Application |
70-98% | Immunograde purity, antibody production |
80-98% | Non-sensitive screening assays |
90-98% | Enzymology, bioactivity studies |
95-98% | Bioassays receptor-ligand studies, structural studies |
What is the IUPAC amino acid code?
Alanine | Ala | A | Methionine | Met | M |
Cystein | Cys | C | Asparagine | Asn | N |
Aspartic Acid | Asp | D | Proline | Pro | P |
Glutamic Acid | Glu | E | Glutamine | Gln | Q |
Phenylalanine | Phe | F | Arginine | Arg | R |
Glycine | Gly | G | Serine | Ser | S |
Histidine | His | H | Threonine | Thr | T |
Isoleucine | Ile | I | Valine | Val | V |
Lysine | Lys | K | Tryptophan | Trp | W |
Leucine | Leu | L | Tyrosine | Tyr | Y |
How do I know if my custom peptide will be soluble?
- The peptides should remain sealed and be kept under cool, dry condition & away from light. For short term storage such as a few days to 2 months, the lyophilized peptides should be stored at 40 oC.
- For long term storage, we recommend to store the peptide in a deep freezer at -800 oC. This will keep the peptide stable for years; however the contamination with moisture will greatly affect the long term stability of peptide. If the peptides need to be frequently taken from the stock, it strongly recommended to make a series of aliquots from the stock.
- We suggest customer to aliquot into few tubes and store at freezer to avoid contamination and frequent repetitive freeze-thaw cycle of the peptides.
The solubility of a peptide is dependent mainly on its polarity. The following are common solvent use to dissolve the peptide.
Type of Synthetic Peptide | Solvent |
1. Acidic peptides | Basic buffer |
2. Basic peptides | Acidic solutions |
3. Hydrophobic peptides & neutral peptides (contain large number of hydrophobic or polar uncharged amino acids) | DMSO, DMF, acetic acid, acetonitrile, methanol, propanol, or isopropanol, and then diluted using water. |
[Note 1: For (3), dissolve in small amount of the suggested organic solvent and dilute using water.]
[Note 2: DMSO should not be used with peptides that methionine or free cysteine because it might oxidize the side-chain.]
Charge of Peptide | Amino Acid Residue |
Positive (+) | K, R, H, and the N-terminus |
Negative (-) | D, E, and the C-terminus |
Hydrophobic uncharged residues | F, I, L, M, V, W, and Y |