Using PCR primers
We keep PCR primers in this Google Doc. Access is required, ask for it if you do not have it.
Designing PCR primers
Buying PCR primers
As of April 1 2026, these options are the best offerings from Eurofins:
| Size | Product |
|---|---|
| 10..33 | SaltFree Oligo NightXpress €0.29/base |
| 34..35 | PCR Primer in Tubes = €9.90 |
| 36..120 | Custom DNA Oligos in Tubes |
Receiving primers
We normally buy lyophilized (freeze-dried) primers. This is a good option in terms of high stability during shipping. This means that you have to reconstitute (dissolve or dilute) the dried primers with water. The PCR primer stocks should be reconstituted to a final concentration of 100 pmol/µL (equivalent to 100µM). Eurofins provide a volume to add to the primer (see orange ring in the figure below).
- Always use filtered tips to dissolve the primer stocks in ddH2O (ultrapure).
- Always use filtered tips when pipetting from primer stocks.
- Never use the primer stocks directly. Dilute PCR primers to 10 µM working solutions (You can use normal tips for the ddH2O used to dilute the primers.)
- Mark the tubes with 10 µM primer with the PCR primer number and keep it in the fridge.
- Do not dilute more primer than necessary, usually 100 to 200 µL is more than enough.
