Key Takeaways
- •Peptide length: Sequences of 6 to 15 amino acids are standard. Shorter peptides may lack specificity, while longer ones can be more difficult to synthesize.
- •Purity: 70 percent purity is sufficient for most screening. If your assay is sensitive to impurities, consider clinical-grade options.
- •Scale: 2 µmol is typical. For assays requiring larger amounts, request a custom scale.
- •Modifications: Plan modifications carefully based on your assay requirements. Common modifications include biotin for capture assays or fluorophores for detection.
- •Plate format: 96-well plates are convenient for high-throughput work. Ensure your liquid handling equipment is compatible.
Custom peptide libraries allow researchers to screen large numbers of peptide sequences simultaneously, accelerating drug discovery, epitope mapping, and functional studies. When ordering a research-grade library, understanding the standard specifications and available options is critical to obtaining useful results.
This article covers the typical parameters for custom peptide libraries, including peptide length, purity levels, synthesis scale, modifications, and plate formats. We also explain the difference between research-grade and clinical-grade quality to help you choose the right option for your project.
Key Specifications for Research-Grade Peptide Libraries
Custom peptide libraries are typically synthesized with a peptide length of 6 to 15 amino acids. This range is common because it covers most bioactive peptide sequences while keeping synthesis practical and cost-effective.
All peptides in a research-grade library are produced sterile and free of endotoxins and cross-contamination. This ensures that results are not compromised by microbial contamination or carryover from previous syntheses.
The standard purity for research-grade custom peptide libraries is 70 percent. This level is sufficient for many screening applications where absolute purity is less critical than sequence diversity and throughput. For projects requiring higher purity, clinical-grade libraries are available.
The standard synthesis scale is 2 µmol (micromoles). This scale provides enough material for most screening assays while keeping costs manageable. If you need a different scale, you can request that through the supplier's contact form.
Available Formats and Modifications
Peptides in a custom library are typically delivered lyophilized in 2 ml vials. This format ensures stability during storage and allows easy reconstitution when needed.
A variety of peptide modifications can be applied to the library, depending on your research needs. Common modifications include N-terminal acetylation, C-terminal amidation, biotinylation, fluorescent labels, and phosphorylation. These modifications can affect peptide stability, solubility, or detectability in assays.
Researchers can also request that peptides be compiled in 96-well plates. This format is convenient for high-throughput screening because it allows direct use with automated liquid handlers and plate readers. If you need this option, specify it in the comment field of your quote request.
Research Grade vs. Clinical Grade Quality
Custom peptide libraries are available in two quality grades: research grade and clinical grade.
Research-grade libraries are designed for basic research and screening applications. They offer 70 percent purity, a 2 µmol scale, and standard lyophilized delivery in vials. This is the most cost-effective option for initial screening or structure-activity relationship studies.
Clinical-grade libraries are intended for more demanding applications, such as preclinical or clinical studies where higher purity and stricter quality controls are required. To request a quote for clinical-grade quality or individual synthesis scales, use the supplier's contact form rather than the standard quote request form.
How to Request a Quote for a Custom Peptide Library
When requesting a quote for a research-grade custom peptide library, you will need to provide specific information. Fields marked with asterisks are mandatory.
You should include the desired peptide sequences, any modifications, and the number of peptides needed. If you want the peptides compiled in 96-well plates or require other special handling, note these requirements in the comment field.
For clinical-grade quality or synthesis scales other than the standard 2 µmol, use the contact form instead of the standard quote request form. This allows the supplier to provide a tailored quote based on your specific needs.
Ready-to-Ship Catalog Peptides and Peptide Pools
In addition to custom libraries, many suppliers offer over 1,000 ready-to-ship catalog peptides and peptide pools. These are pre-synthesized and available for immediate purchase, which can save time if your research uses common sequences.
Catalog peptides are useful for controls, standard curves, or preliminary experiments. Peptide pools combine multiple sequences into a single vial, which is helpful for screening large numbers of peptides in a single assay.
Practical Considerations for Using Custom Peptide Libraries
When designing a custom peptide library, consider the following points:
- Peptide length: Sequences of 6 to 15 amino acids are standard. Shorter peptides may lack specificity, while longer ones can be more difficult to synthesize.
- Purity: 70 percent purity is sufficient for most screening. If your assay is sensitive to impurities, consider clinical-grade options.
- Scale: 2 µmol is typical. For assays requiring larger amounts, request a custom scale.
- Modifications: Plan modifications carefully based on your assay requirements. Common modifications include biotin for capture assays or fluorophores for detection.
- Plate format: 96-well plates are convenient for high-throughput work. Ensure your liquid handling equipment is compatible.
Conclusion
Custom peptide libraries are powerful tools for high-throughput screening and research. By understanding the standard specifications, available modifications, and quality grades, you can request an accurate quote and obtain peptides that meet your experimental needs. Whether you need research-grade libraries for initial screening or clinical-grade quality for advanced studies, the ordering process is straightforward when you provide the correct information.
For more resources on peptide research, explore our Peptide Glossary and Free Peptide Tools to support your work.