Custom Peptides

Peptides play a key role in biochemistry, pharmacology and neurobiology for structural and functional studies. They are also important for a variety of biological and clinical applications. These include production of monoclonal and polyclonal antibodies for immunological research, the study of antigen-antibody interactions, epitope mapping, structure-function studies, peptidomimetics, receptor studies, and drug design.


Methods for synthesizing peptides are divided into two distinct categories: solution and solid phase. We use the solid-phase peptide synthesis method with Fmoc chemistry. With this method, peptide chains are assembled on a solid support initiating at the C-terminus and progressing towards the N-terminus, by repeating three basic steps: deprotection of the Fmoc alpha amino group, activation of the next protected amino acid as an active ester, and coupling. When the synthesis is complete, the peptide is cleaved from the support with concomitant removal of the side-chain protecting groups. We normally use automated synthesis; for difficult or particular sequences, we employ manual synthesis.

Peptides Purity

Our peptides are purified by Reversed Phase HPLC (RP-HPLC). HPLC purification permits the removal of deletion and truncated sequences, scavengers, and TFA (Trifluoroacetic Acid) used to deprotect and cleave the peptide from the resin, which could otherwise be extremely toxic and interfere with the expected activity of the peptide.
We offer three different degrees of purity:

  • Crude peptides for generation of peptide libraries and for preliminary experimental screening
  • 70% for immunological purposes
  • 95% for biological activity studies in vitro, animal studies, and for biochemical reactions, such as binding experiments or receptor studies.

Our peptides are purified by Reversed Phase HPLC (RP-HPLC). HPLC purification permits the removal of deletion and truncated sequences, scavengers, and TFA (Trifluoroacetic Acid) used to deprotect and cleave the peptide from the resin, which could otherwise be extremely toxic and interfere with the expected activity of the peptide.

We offer three different degrees of purity:

PurityPeptides length aa*
Crude 8-25 aa
> 70% 8-25 aa
>95% 8-25 aa

*if you require peptides falling outside of our standard length, please inquire

In addition to our standard peptide synthesis service, we offer several peptide modifications for a variety of applications.

Peptides Modifications

Cat. No.Modifications
OP-2016 N-terminal Acetylation (Acetyl)
OP-2017 C-terminal Amidation (Amide)
OP-2018 N-terminal Biotin
OP-2019 C-terminal K-Biotin
OP-2020 N-terminal 5-6 FAM
OP-2300 N-terminal 5-FAM (single isomer)
OP-2021 N-terminal 5-6 TAMRA
OP-2301 N-terminal Lissamine
OP-2302 N-terminal DTPAGlu
OP-2303 N-terminal DOTA
OP-2304 Lys (DOTA)
OP-2305 Lys (5(6)-FAM); Lys(Dabcyl); Asp/Glu (EDANS)
OP-2022 Spacer (linker) 8-amino-3,6-dioxa octanoic acid / amino hexanoic acid
OP-2023 Conjugation to a Carrier Protein (KLH, BSA, OVA)
OP-2024 2 / 4-branched MAP resin
OP-2025 internal Cys-Cys Cyclisation
OP-2026 internal Ser/Tyr/Thr Phosphorylation (per aa)
OP-2306 D-Isoleucine (I) price per a/a
OP-2307 D-Arginine/D-Asparagine/ D-Glutamine-D/Tryptophan-D/Tyrosine (R-N-Q-W-Y) price per a/a
OP-2308 All remaining D a/a price per a/a

For enhanced immunogenicity we are able to provide you with two modification options:

a. Conjugation

Synthetic peptides are normally small molecules, which are not able to elicit a significant immune response. However, when they are coupled to a larger carrier molecule, the immune system will then respond to the hapten-carrier complex producing antibodies against the peptide and the carrier protein. We offer you the choice between the most commonly used carrier-proteins: BSA, KLH, OVA and others upon request. There is a variety of reagents used for peptide to the carrier linkage:

  • Glutaraldehyde, which cross-links primary NH2-groups on the peptide to those of the protein
  • Sulfo-SMCC (Sulfosuccinimidil 4-N-maleimidomethyl-cyclohexane-1-carboxylate), a heterobifunctional reagent that binds, in a two-step reaction, the primary amines of the carrier protein and the sulphydryl group of the cysteine of the peptide. For peptide sequences lacking cysteine residues, we suggest the addition of a cysteine either at the N- or C-terminus of the peptide depending on several criteria


An alternative system to produce antibodies using peptide-conjugates is to use MAPs (Multiple Antigenic Peptides). In this case, the peptide chain grows on a 4 branching lysine core. Lysine has two amino groups and can be used to build up a large branching lysine complex.

In general, we recommend to use the 4-branch MAP resin for peptides containing more than 15 amino acid residues and the 8 branch MAP resin for peptides shorter than 15 amino acids. The desired epitope should be at the distal flexible end of the peptide. This approach produces a higher titer of anti-peptide antibodies, eliminating the presence of contaminant anti-carrier antibodies.

Peptides Scales / Yields

Upon request, we offer small, medium, and large scale synthesis of peptides. Our small scale service generally provides 2 or 5 mg of pure peptide, which is sufficient for immunological studies or for antibody production. In case your application requires higher quantities, our routine medium or large scale service can provide you with 10, 20, 50, or 100 mg of peptide, respectively. Larger quantities, yielding approximately from 1 gram, are also available upon request (bulk synthesis).

Multiple Peptide Synthesis

Our peptide libraries have been designed for high throughput screening to study epitope mapping, peptide-protein interaction, protein scanning and characterization and much more. We offer 24, 48 or 96 peptides synthesized together and delivered as lyophilised products in individual labelled tubes. Quantity expected is around 2mg for each peptide.

You can select from the following options:

Purified Peptide librariesLenghth in aaPurityPurification and QCDelivery time
Crude 24/48/96 8-15 -- HPCL and MS 3 weeks
Puriflex 70 8-15 >70% HPCL and MS 4 weeks
Puriflex 80 8-15 >80% HPCL and MS 4 weeks
Puriflex 95 8-15 >95% HPCL and MS 4 weeks

For very hydrophobic peptides yields may be very low. We do not guarantee the purity or success of any one peptide on the same synthesis.

Peptides are also available non amidated (-COOH free).

DNA Peptide conjugates

We can couple DNA / PTO oligonucleotides to peptides. Any orientation is possible (N-terminus or C-terminus of peptide linked to 5’ end or 3’ end of oligonucleotide).
We will prepare a quotation upon request.
Please send the sequence of the peptide and the oligonucleotide.
Please mention the orientation.
Please mention how many nnol you need of the conjugate.

Peptides Quality Control & Documentation

Our standard QC methods performed to assure the integrity and purity of the delivered products are

  • MALDI-ToF mass spectrometry (verification of peptide composition)
  • Analytical RP-HPLC (Illustration of peptide purity)

Supporting documents of each product delivered include

  • Synthesis report
  • Maldi-ToF spectrum
  • HPLC chromatogram*

*this does not apply to peptides delivered in crude extracts


You can send us an email to with the following information:

  1. Shipping and billing address
  2. Sequence (1 letter code, see FAQs for more information) including potential modifications (type and position)
  3. Quantity you would like to order in mg
  4. Desired purity in %

If you have any question, just contact