Resuspension Calculator
Plan oligo and primer resuspension by calculating the diluent volume needed for a desired stock concentration. The same relationship can also solve backward for amount or target concentration.
Result
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Quick Answer: The core formula is Volume = Amount / Desired concentration. When the amount is fixed, a higher target concentration always means a smaller resuspension volume.
How to Calculate Resuspension
- Choose the missing value: Solve for volume, amount, or desired concentration from the same amount-over-concentration relationship.
- Enter the known values: Use the oligo amount from the certificate or synthesis report and the concentration you want for the stock.
- Check the unit prefixes: nM, uM, nmol, and pmol differ by large factors, so verify the prefixes before mixing.
- Prepare and label the stock: Use the calculated volume as a planning value and confirm it against your lab workflow.
Resuspension Calculator Formula
Volume = Amount / Desired concentration
| Variable | Meaning | Unit |
|---|---|---|
| Volume | Diluent volume required | uL, mL, or L |
| Amount | Oligo or primer amount | mol-based amount |
| Desired concentration | Target stock concentration | M-based concentration |
Worked Examples
Example 1 - Find resuspension volume
- Amount: 25 nmol
- Desired concentration: 100 uM
Result: Volume = 250 uL
A 100 uM stock from 25 nmol needs a quarter milliliter of diluent.
Example 2 - More dilute stock
- Amount: 50 nmol
- Desired concentration: 20 uM
Result: Volume = 2.5 mL
Lower target concentrations require more diluent for the same oligo amount.
Example 3 - Find concentration from amount and volume
- Amount: 10 nmol
- Volume: 200 uL
Result: Desired concentration = 50 uM
This is a common stock-planning calculation when a fixed resuspension volume is preferred.
Resuspension Reference Table
| Range | Meaning | Action |
|---|---|---|
| Small volume | A concentrated stock solution. | Make sure the stock will still be easy to pipette accurately. |
| Large volume | A more dilute stock solution. | Confirm that the larger volume is practical for storage and downstream use. |
| Very high target concentration | Minimal diluent volume required. | Double-check units because tiny input errors strongly affect the result. |
Frequently Asked Questions
Here, resuspension means adding a liquid such as water or buffer to a dried oligo or primer so it becomes a usable stock solution.
The calculation is the same. What changes is the amount you start with and the stock concentration you want for your lab workflow.
Because volume equals amount divided by concentration. If the numerator stays fixed and the denominator gets larger, the result gets smaller.
Yes. If you know the amount and the volume you want to use, the page can solve for the resulting stock concentration.
That depends on your protocol and storage needs. The calculator only handles the amount-concentration relationship, not the buffer choice.
Note: Use this as a planning and verification tool. Follow your oligo certificate, assay protocol, and lab storage guidance for the actual preparation.
References
Last reviewed: March 14, 2026