A Beginner’s Guide to Peptide Calculations for Lab Research
Dec 5th 2025
Scientists often need to calculate the concentration of peptide solutions for experiments. While this may sound complicated, the basics of calculating solution concentration are easy to understand.
⚠️ For research use only. Not for human or animal use.
Step 1: Know Your Peptide Amount
Start with the mass of peptide you are using, measured in milligrams (mg). For example, you may have a vial containing 10 mg of peptide.
Step 2: Decide on Your Solvent Volume
The solvent volume determines how concentrated your solution will be, measured in milliliters (mL). For instance, adding 1 mL of sterile solvent to 10 mg of peptide gives a 10 mg/mL solution.
Step 3: Use the Basic Formula
- Concentration (mg/mL) = Peptide Mass ÷ Solvent Volume
- Example: 10 mg of peptide ÷ 1 mL of solvent = 10 mg/mL solution
Optional: Use Online Peptide Calculators for Complex Conversions
If you have more complex requirements — for example converting between mg, mcg, mL or calculating dose per syringe unit — you might find general math tedious or error‑prone. The following tools may help (remember: research use only):
Step 4: Quick Reference Table of Concentrations
Here’s a quick reference table that shows some common peptide mass / solvent volume combos to help you visualize expected concentrations:
| Peptide Mass (mg) | Solvent Volume (mL) | Resulting Concentration (mg/mL) |
|---|---|---|
| 5 | 1 | 5 |
| 10 | 1 | 10 |
| 10 | 2 | 5 |
| 20 | 4 | 5 |
Step 5: Safety & Best Practices
- Always use sterile technique — sterile solvent, sterile syringes, and clean workspace.
- Label all vials clearly with concentration, date, and lot number.
- Store reconstituted peptides under recommended conditions (e.g. refrigeration or as specified by manufacturer).
- Document all calculations and procedures — this is critical for reproducibility in research settings.
Disclaimer:
This guide and the linked calculators are intended strictly for laboratory research or educational purposes. They are not medical advice, nor are they intended to support or facilitate any human or animal dosing. Always verify calculations independently and follow all applicable regulations and safety protocols.