Not For Human Use, Lab Use Only.
Special Price 117.7 USD
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Peptide Purity (HPLC)
The sequence of the minimal ALFA-tag (SRLEEELRRRLTE) is inspired by an artificial peptide (SRLEEELRRRL) reported to form a stable α-helix in solution24. It was selected based on the following criteria: (i) It features a high alpha-helical content, (ii) The sequence is absent in common eukaryotic model systems, (iii) It is hydrophilic and neutral at physiological pH while retaining moderate hydrophobic surfaces and (iv) It does not contain any primary amines that are modified by aldehyde-containing fixatives. The additional Thr-Glu (TE) dipeptide was added to the original peptide to neutralize its positive net charge and thus fully comply with the selection criteria defined above. To minimize any potential influence of neighboring secondary structures, the minimal ALFA-tag sequence was in addition framed by prolines.
Normally, this peptide will be delivered in lyophilized form and should be stored in a freezer at or below -20 °C. For more details, please refer to the manual:Handling and Storage of Synthetic Peptides
- Götzke, H., Kilisch, M., Martínez-Carranza, M. et al. The ALFA-tag is a highly versatile tool for nanobody-based bioscience applications. Nat Commun 10, 4403 (2019).
About TFA salt
Trifluoroacetic acid (TFA) is a strong acid, which is commonly used to cleave synthesized peptides from solid-phase resins and is also used to improve HPLC performance in the peptide purification step. By default, custom peptides are delivered as lyophilized TFA salts, and can contain as much as 10-45% TFA.
TFA in custom peptides can cause inexplicable discrepancies in subsequent assay data. For instance, TFA in nM concentrations has been shown to interfere with cellular assays, inhibiting cellular proliferation in some instances, and increasing cell viability in others . It has also been found to be an unintended allosteric modulator of the glycine receptor, GlyR.
TFA Removal Service is recommended for:
- Peptides that will be used in cellular assays
- Peptides that will be used as APIs or in manufactured products
- For hydrophilic peptides containing numerous basic residues
Related Products / Services
• Peptide Services: NovoPro's peptide synthesis services include standard chemical peptide synthesis, peptide modification, peptide libraries, and recombinant peptide expression.
• Standard Peptide Synthesis: NovoPro offers quality peptides at the most competitive prices in the industry, starting at $3.20 per amino acid. NovoPro provides PepBox – Automatic Quote Tool for online price calculation.
• Peptide Modifications: NovoPro offers a wide range of peptide modification services including isotope labeling (2H, 15N, and 13C), multiple disulfide bonds, multiple phosphorylations, KLH, BSA, ovalbumin, amidation, acetylation, biotin, FITC, etc.
Please note: All products are "FOR RESEARCH USE ONLY AND ARE NOT INTENDED FOR DIAGNOSTIC OR THERAPEUTIC USE"