- What is your peptide synthesis process?
At United Peptide, we believe that quality products save you time. Our peptide synthesis know-how and production facilities have been in place since 2001 . To date we have synthesized over 23,000 research peptides (5-100 mg scale) for academic research and top tier pharmaceutical laboratories around the world. Peptides are synthesized 7 days a week, 24 hours a day, are delivered as lyophilized dry powders and shipped overnight with all pertinent quality control datasheets. Peptides are normally shipped within 2-3 weeks from the reception of your order.
- How do you know the chance of success before you start systhesizing ?
Feasibility evaluations are conducted on all peptide sequences prior to synthesis. Using commercial software and based on our own internal database of difficult to synthesize sequences, a determination is made regarding the complexity of the synthesis. This includes a hydrophobicity/hydrophilicity plot (Hoop-Woods and Kyte-Doolittle algorithms).
- What methods do you use for peptide synthesis?
United Peptide uses state-of-the-art chemistries and fully automated instruments for the production of custom peptides. Two methods are available, solid phase FMOC based chemistry and United Peptide's proprietary solid phase chemistry for the rapid synthesis of large custom peptide libraries. Peptides are synthesized with multiple couplings per step to ensure sequence integrity, once synthesized these are cleaved from the solid support, precipitated and washed repeatedly with ether. Both methods provide routine access to peptide of 6 to 25 amino acids in length, longer peptides are evaluated on a case by case basis. FMOC synthesis can provide peptides in numerous scales, from 1 mg up to gram scales.
- What is your purification process and QC ?
All peptides are analyzed by Mass Spectrometry to determine the molecular weight of the synthesized peptide, free of charge. Comparison of the theoretical molecular weight with the experimentally determined molecular weight confirms the absence of amino acid deletions or double couplings. MS is an excellent method for determining the presence of the desired product, but an inadequate method for the determination of purity. Due to the variant efficiencies of peptide ionization in the MS instrument, peak intensities in MS spectra are not necessarily quantitative. For this reason all non-crude peptides at United Peptide are analysed by Reverse-Phase HPLC (RP-HPLC) to determine purity.
Precipitated peptides are analysed on a Waters Alliance, RP-HPLC instrument equipped with an auto-sampler for continuous analysis. Peptides that meet or exceed the purity requirements are then lyophilized, packaged and shipped to the customer at room temperature by overnight dispatch. Peptides are available as crude,desalted, >70%, >75%, >80%, >85%, >90%, >95% and > 98 % purity depending on your research applications