We prepare mg to multi-g amounts of fully characterized peptides for research. Most syntheses are achieved using solid-phase resin and Fmoc chemistry whilst solution-phase approach is utilized where appropriate for more demanding synthesis or special structural features. We further purify your peptides using reversed-phase HPLC to different levels of purities. We will assist you and recommend the optimum purity level required for your particular application. Peptides are sold for in vitro research use only and they are not intended for medical or diagnostics applications.
The table below describes our classical, most frequently requested syntheses. Please contact us with your sequence(s), amount and purity level and we will always respond with a very competitive offer.
synthesis scales (mg)
|(I)||2 mg (minimum amount)|
|(II)||5 mg to 30 mg in increments of 5 mg|
|(III)||30 mg to 100 mg in increments of 10 mg|
|(IV)||0.1 g to 1 g in increments of 50 mg|
|(V)||1 g to 10 g in increments of 500 mg|
|Purity levels:||>70%, >80%, >90%, >95% and >99%|
|Analytical Data:||HPLC trace (220 nm), mass spectrum (EI, MALDI-TOF) & dissolution conditions|
|Peptide Length:||Standard:5-30 aa ; Routine: 31-60 aa ; Maximum length about 100 aa|
|Structure:||Unblocked termini (i.e. NH2- and -COOH ends)|
|Counter ions:||Standard: Trifluoroacetate (tfa); Option: acetate or chlorine|
HPLC purification options include guaranteed purities >70%, >80%, >90%, >95% and a unique ultra-pure >99% grade for demanding experiments.
Purification is performed by preparative or semi-preparative reversed-phase HPLC. We typically use C8 or C18 columns with linear gradients of acetonitrile in 0.1% aqueous tfa with UV monitoring at 220 nm.
HPLC elution may be monitored with UV detector set at longer wavelength for peptides containing aromatic amino acids.
The crude peptide synthesis contains by-products resulting from failed coupling cycles (i.e. truncated chains), and further oxidation, modification, or hydrolysis of side chains arising during cleavage and deprotection. The extent of impurities depends upon peptide length and primary sequence. Depending upon your specific application we would recommend purification levels along the following guidelines.
Purity >70%: Polyclonal antibodies production; preliminary library screenings; higher levels should be considered for peptides > 20aa.
Purity >80%: Polyclonal antibodies production with long peptides; qualitative immunoassays (ELISA, competition, depletion…)
Purity >90%: Polyclonal mono-specific antibodies; affinity column making; structure-activity studies; qualitative biochemical assays (enzyme activity, specificity…).
Purity >95%: quantitative immunoassays (ELISA, competition, depletion…); quantitative biochemical assays (enzyme activity, kinetics…); generally recommended with modified peptides; preliminary structural analysis (NMR,…).
Purity >99%, ultra-pure: Sensitive bioassays; cell culture assays; quantitative bioassays; structural studies (Crystalography, NMR,…).
Peptides are charged molecules. Standard reversed-phase HPLC purification allows for the isolation of pure peptides that are further freeze-dried yielding peptides preparations that comprise trifluoroacetate (tfa, CF3COO-) as counter-ions. Some applications require the removal of tfa. We offer ion exchange option to acetate (CH3COO-) or chlorine (Cl-) salts.
We recognize that quality and reliability are central to our customers. As a result no peptide leaves our laboratories unless it has fully complied with our stringent QC standards.
All our peptides are weighted and supplied as a stable lyophilized powder with comprehensive documentation. Synthesis report includes analytical HPLC trace verifying purity, a mass spectrum ensuring integrity of the desired full-length peptide and dissolution conditions. Lead time will vary with length, scale, purity, and modifications ordered. Our average turn around is shown in the table below, for standard synthesis scales and purities. Our customers are well advised when synthesis difficulties are encountered and product dispatch is delayed.
|Synthesis||25 mg, >70%||25 mg, >80%||25 mg, >90%||25 mg, >95%||25 mg, >99%|
|Average (*)||approx. 2 weeks||approx. 2 - 3 weeks||approx. 2 - 3 weeks||approx. 3 weeks||approx. 3 weeks|