Frequently asked questions
What are Peptides?
Peptides are short chains of amino acids — the essential building blocks of proteins. When two amino acids join together, they form a peptide bond. This bond occurs when the carboxyl group of one amino acid reacts with the amino group of another, releasing a water molecule (a process known as dehydration synthesis).
By repeating this bonding process, additional amino acids can join the chain, forming longer sequences called polypeptides. When a polypeptide becomes sufficiently long and structurally complex, it can form a complete protein.
Peptides occur naturally in living organisms through translation, where ribosomes assemble amino acids into chains based on genetic instructions.
In laboratory settings, peptides can also be synthesized through advanced chemical techniques, allowing researchers to create precise amino acid sequences for targeted scientific applications.
How Are Peptides Formed?
Peptides form when amino acids connect through peptide bonds created by dehydration synthesis. This chain-building process continues until a polypeptide is formed. Depending on the length and complexity of the chain, the structure may become a functional protein.
In nature, the ribosome drives this process using genetic code.
In research settings, scientists intentionally create peptides using controlled synthesis methods, enabling custom sequences optimized for study, analysis, and experimentation.
Types of Peptides
Peptides vary widely in structure and function. Some common categories include:
Signal Peptides
Guide proteins to specific locations inside or outside the cell.
Hormonal Peptides
Act as chemical messengers in the body (e.g., insulin, glucagon, growth hormone, oxytocin).
Neuropeptides
Support neurotransmission and regulate nervous system responses (e.g., substance P, enkephalins, endorphins).
Antimicrobial Peptides
Provide defense against pathogens (e.g., defensins, cathelicidins).
Enzyme-Active Peptides
Possess enzymatic activity, such as ACE-inhibiting peptides used to regulate blood pressure.
Cell-Penetrating Peptides
Can cross cell membranes to deliver molecules like drugs or genetic material.
Vaccine Peptides
Trigger immune responses for experimental vaccine development.
Targeted Therapy Peptides
Bind specific receptors or molecules for targeted treatments (often studied in cancer research).
Structural Peptides
Support tissue integrity and structure (e.g., collagen peptides).
These categories highlight the incredible diversity and scientific importance of peptides in biological systems and therapeutic research.
Peptide Reconstitution — Dr Peptides Guide
Lyophilized Peptides
Most research peptides are supplied in lyophilized (freeze-dried) form.
Lyophilization removes water through freezing and sublimation, creating a stable, dry powder. This process protects peptides from degradation, microbial growth, and structural breakdown — making them easier to ship, store, and handle.
Lyophilized peptides remain potent for long periods and can be reconstituted at any time using a suitable solvent.
How to Reconstitute Peptides (For Research Use Only)
Follow proper laboratory technique to ensure accuracy and quality in your research.
1. Gather Materials
Lyophilized peptide
Suitable solvent (Dr Peptides recommends pharmaceutical-grade bacteriostatic water)
Sterile syringe
Additional sterile vial (if needed)
2. Determine Concentration & Volume
Calculate the desired peptide concentration for your experiment and the solvent volume required.
3. Add Solvent
Draw the correct amount of solvent (usually 1–3 mL depending on the peptide) and gently inject it into the vial, allowing it to run down the glass wall to prevent foaming or structural disruption.
4. Dissolve Gently
Swirl the vial lightly until dissolved. Avoid shaking, which can denature sensitive peptides.
5. Allow Complete Dissolution
Let the peptide fully dissolve. Ensure no particles remain before use.
6. Store Correctly
Follow proper storage conditions immediately after reconstitution to maintain stability and purity.
7. Record Everything
Document concentration, solvent volume, date, and any experimental details — essential for reproducibility.
Always consult qualified laboratory professionals to ensure proper handling procedures for your specific peptide of interest.
Best Practices for Storing Peptides
Proper storage is essential to preserve peptide purity, stability, and research accuracy.
Short-Term Storage
- Store unopened lyophilized peptides in a cool, dark environment.
- For immediate or near-future use (days to months), keep refrigerated at 4°C (39°F).
- At this temperature, most lyophilized peptides remain stable 1–2 years (unmixed).
Room Temperature Stability
Lyophilized peptides can remain stable at room temperature for several weeks if kept away from direct sunlight and heat.
Long-Term Storage
- For storage beyond several months, freeze peptides at –20°C or lower.
- Freezing greatly extends shelf life and protects structural integrity.
Avoid Freeze–Thaw Cycles
Repeated thawing can degrade peptides.
Use aliquots whenever possible to prevent unnecessary freeze–thaw exposure.
Avoid Frost-Free Freezers
Frost-free freezers experience temperature fluctuations that can compromise peptide stability.
Use a standard, non-cycling freezer for long-term storage.
By following these best practices, you can maintain peptide purity and ensure consistent, reliable experimental results.
