Why is the quantity of my peptide less than "x" mg/g, or less than "x" % purity?

When you receive your synthesized peptide, it is in the form of a lyophilized powder which is composed of the peptide material, counter ion and bound water. Therefore, when you request 1mg of a peptide, by the industry standard, you are placing an order for 1mg of lyophilized powder, so the net quantity of your target peptide will be a little less.

If you feel the quantity or purity you received is significantly less than what we proposed for the project, there may have been an error on our end, so please contact us at peptide@biobasic.com and we will do our best to rectify the error.

What is the actual quantity of my target peptide in the lyophilized powder?

If you know both the peptide purity and the net peptide content, you will know how much of your actual target peptide is in the lyophilised powder deliverable.

What is my peptide's purity? What does it refer to?

HPLC data provides information regarding the purity of the peptide i.e. it will tell you the percentage of your target peptide in relation to the peptide material only (NOT the entire lyophilized powder).

What is net peptide content? How do I obtain this data?

The net peptide content will tell you the percentage of the peptide material in relation to the entire lyophilized powder. Typically, the net peptide content is 60-90%. If more accuracy is required, the net peptide content can be obtained by Amino Acid Analysis (AAA) or Elemental Analysis (EA).

Do I choose Amino Acid Analysis (AAA) or Elemental Analysis (EA)?

AAA requires a small quantity of the peptide for analysis and is less accurate and cheaper to perform. EA requires larger quantities of the peptide for analysis and more accurate and costs a little more to perform. Generally if it is the net peptide content is important to know for your research, then it is better to use the more accurate, EA for your project.

How are peptides synthesized?

We have both manual and automated synthesizers.

How is the synthesis of the correct sequence assured?

We provide both MS and HPLC with all peptide synthesis to ensure the sequence is correct.

Are generic purification systems used?

We usually perform the purification by preparative RP HPLC. 220 nm, Mobile phase: A:0.1%TFA+H20;B:0.1%TFA+ACN.

How are chromatographic conditions for each peptide selected?

We select a suitable gradient to test the peptide according to its property, generally with a change rate of 1%/min, running 30min.

How should I store my peptides?

All peptides are in lyophilized form, which are stable at room temperature. However to ensure a long shelf life please use a freezer. It is recommended to store the lyophilized form at -20°C, or preferably at -70°C for peptides in solution. Please ensure peptides are in sealed containers to minimize peptide degradation.

How should I dissolve peptides?

Our solubilization guidelines can be found on our Solubility Testing page.

Which level of peptide purity should I select for my research?

Crude: Non-sensitive screening assays.
>70%: Non sensitive screening assays, exploratory or relative MS assays.
>80%: Non quantitative binding assays, ELISPOT assays, Polyclonal antibody production.
>90%: Post-translationally modified peptides for polyclonal antibody productions,
            receptor-ligand assays.
>95%: Quantitative Mass Spectrometry SRM/MRM assays, monoclonal antibodies, quantitative
            receptor-ligand assays, enzyme kinetics, cell/tissue culture, phosphorylation studies.
>98%: NMR, X-ray structural studies.

What salt form do standard peptides come in?

Peptides usually have TFA salts. If you require TFA removal, Acetate or hydrochloride is also available.

What is the minimum scale for one order (i.e. minimum order size)?

The minimum amount to be ordered is 1 mg. There is no maximum amount.

What are the Terms and Conditions for Peptide Synthesis?

Please click here for the terms and conditions for our Peptide Synthesis services.