Peptide synthesis is supported by a Rainin Symphony 12 channel multiple peptide synthesizer, allowing for synthesis at variable scales ranging from 25mMol to 0.5mMol. Additionally, a Protein Technologies Prelude, which was beta-tested in this facility, provides synthesis at smaller scales (1 to 10mMol). Turn around times for synthetic peptides range from 2-3 weeks, depending on whether purification is requested. A variety of modified amino acids can be incorporated, including hydroxyproline, methylated amino acids, and non-standard amino acids such as ornithine and aminobutyric acid. The Genomics Shared Service has been very successful in phospho-peptide synthesis, as well as development of synthesis strategies to effectively label peptides with a variety of labels including biotin, fluorescein and rhodamine derivatives, and incorporating multiple labels in a peptide. Other specialty services that the facility excels at include cyclic-peptide synthesis via amide-bond formation and disulfide bridging, synthesis of multi-branched, dendrimer-like peptides, and synthesis of peptide-DNA hybrids. Manual synthesis is employed for small di- or tri-peptides.
Drs. Campbell and Ambulos has been heavily involved in synthetic methodologies, including synthesis of labeled peptides and multi-branched cationic peptides, as well as advocating stringent analytical methods for the analysis of synthetic peptides (Ambulos, et. al., in, Albericio and Kates, Eds., Solid Phase Synthesis: a Practical Guide, pp747-785,2000, Bibbs, et. al., J. Biomolec. Technol., 11:155-165,2000, Zhang, et. al., in, Heiser, W.C., ed., Gene Delivery to Mammalian Cells: Vol. 1: Nonviral Gene Transfer Techniques, pp33-52, 2003, Leng, et. al., J. Gene Med., 7:977-986, 2005, Leng, et. al., Drug News Perspect.,20:77-86).
The facility has done a great deal of large-scale peptide synthesis and purification, including peptides included in the National Institutes of Standards and Technology Reference Materials RM8327, Peptide Standards for Molecular Mass and Purity Measurements.
Peptide purification is available with a choice of two levels of purity, >70% and >95%. Purification is done by reversed phase HPLC, although ion exchange chromatography is available if necessary. Peptides are provided as lyophilized powder, with gross weights provided. Provided along with the peptide are the analytical data, both HPLC and MALDI-TOF mass spectra. The cost for synthesis (without purification) or synthesis and purification to the two levels of purity are detailed in the chart below as a cost per amino acid.
| Peptide Purity Level | Crude Peptide | >75% Peptide Purity | >95% Peptide Purity |
|---|---|---|---|
| 10μM | $10.00 * | N/A | N/A |
| 25μMole | $15.00 | $25.00 | $35.00 |
| 50μMole | $20.00 | $30.00 | $40.00 |
| 100μMole | $30.00 | $40.00 | $55.00 |
| 250μMole | $50.00 | $60.00 | $75.00 |
* For 10μMole scale, purification, if desired, is a separate charge of $100 per peptide.