Standard synthesis scales
The table below describes our classical, most frequently requested syntheses. We routinely prepare higher amounts (up to several grams) and longer peptides. Please contact us with your sequence(s), amount and purity level and we will always respond with a very competitive offer.
- Fig 1. Synthetic route for synthesis of a bicyclic, branched 21 aa peptide that included a combination of solid phase and solution chemistry approaches.
- Click on figure to enlarge
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Standard Purity levels / Amounts: |
> 99% | 2-5 mg |
| > 95% | 5-10 mg | |
| > 80% | 10-15 mg | |
| > 70% | 20-25 mg | |
| Analytical Data : | HPLC trace (220 nm) & Mass Spectrum (MALDI-TOF) | |
| Peptide Length : | Up to 30 aa | |
| Structure : | Unblocked termini (i.e. NH2- and-COOH ends) | |
Reverse phase HPLC purification
HPLC purification options include guaranteed purities >70%, >80%, >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 or mono-specific antibodies; affinity column making; qualitative immunoassays (ELISA, competition, depletion…); qualitative biochemical assays (enzyme activity, specificity…).
Purity >95%: quantitative immunoassays (ELISA, competition, depletion…); quantitative biochemical assays (enzyme activity, kinetics…); generally recommended with modified peptides; structural studies (Crystal, NMR,…).
Purity >99%, ultra-pure: cell culture assays; quantitative bioassays.
Quality control
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.
- Fig 2. Reverse phase HPLC analysis of a 10-aa peptide containing two aromatic residues (tyr) with dual wavelength recording: 220 nm and 280 nm. Co-elution of both absorptions confirms product purity. C8 column 4.6x250mm, 5μm. Gradient 15-50% acetonitrile in 0.1% aqueous tfa in 25 min, flow rate 1ml/min.
- Click on figure to enlarge
- Fig 3. Every peptide undergoes stringent quality control procedures including analytical HPLC and mass spectrometry.
- Click on figure to enlarge
Fast reliable peptide delivery
All our peptides are weighted and supplied as a stable lyophilized powder with comprehensive documentation. Synthesis report includes analytical HPLC trace verifying purity and a mass spectrum ensuring integrity of the desired full-length peptide. Dispatch 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 is delayed.
| Synthesis | 25 mg, >70% | 15 mg, >80% | 10 mg, >95% | 5 mg, >99% |
| Average (*) | 2 weeks | 2 - 3 weeks | 3 weeks | 3 - 4 weeks |