Ethidium bromide 10 mg/mL stock recipe
A DNA stain stock that makes DNA glow orange under UV; use at 0.5 µg/mL in gels or buffer.
🧮 Volume calculator
| Component | Amount | Final concentration (1X) |
|---|---|---|
| Ethidium bromide | 100 mg | 10 mg/mL |
| Water (distilled) | to final volume |
Steps
- Buy a ready-made solution if possible; if using powder, dissolve in water in a fume hood.
- Wrap in foil or use a brown bottle; store at room temperature.
Good to know
- Add 5 µL per 100 mL gel.
- Safer alternatives: SYBR Safe, GelRed, GelGreen.
⚠ Safety A potent mutagen — wear nitrile gloves, use a designated area and follow institutional disposal rules.
FAQ
Can I post-stain instead?
Yes — soak the gel in 0.5 µg/mL for 15–30 min after the run; background is lower and migration is unaffected.
This is a widely used standard composition. Amounts depend on the hydrate form and purity of your reagents — check the formula weight (FW) on the bottle and follow your institution's safety rules and the manufacturers' instructions.