Search Thermo Fisher Scientific
Loading dyes
The Thermo Scientific portfolio offers several loading dyes for your everyday electrophoresis needs. Loading dyes are used to prepare DNA markers and samples for loading on agarose or polyacrylamide gels. Ready-to-use (RTU) DNA ladders come prepackaged with a loading dye.
DNA loading dyes normally contain:
- Glycerol, to help ensure that the sample easily sinks into the well
- EDTA, which binds divalent metal ions that may interfere with electrophoresis. EDTA also stops metal-dependent enzymatic reactions such as DNA degradation by nucleases
- Tracking dyes (bromophenol blue, xylene cyanol FF, or orange G), which help monitor the progress of electrophoresis by the migration of the dyes
| GeneRuler DNA ladders | MassRuler DNA ladders | O’GeneRuler DNA ladders | TriTrack DNA Loading Dye |
|---|---|---|---|
| 6X DNA loading dye | 6X MassRuler DNA loading dye | 6X Orange DNA loading dye | Available separately, R1161 |
| Two-color tracking of DNA migration | One-color tracking of DNA migration | Two-color tracking of DNA migration | Three-color tracking of DNA migration |
Ordering information
| Loading dye | Description | Quantity | Cat. No. |
|---|---|---|---|
| 6X DNA Loading Dye | Two-color tracking of DNA migration during electrophoresis | 5 x 1 mL | R0611 |
| 6X MassRuler DNA Loading Dye | One-color tracking of DNA migration during electrophoresis | 5 x 1 mL | R0621 |
| 6X Orange DNA Loading Dye | Two-color tracking of DNA migration during electrophoresis | 5 x 1 mL | R0631 |
| 6X DNA Loading Dye & SDS Solution | Two-color tracking of DNA migration during electrophoresis | 5 x 1 mL | R1151 |
| 6X TriTrack DNA Loading Dye | Three-color tracking of DNA migration during electrophoresis | 5 x 1 mL | R1161 |
Buffers for electrophoresis
We offer two Thermo Scientific buffers for electrophoresis: Tris-acetate-EDTA (TAE) and Tris-borate-EDTA (TBE).
- TAE buffer is generally used for electrophoresis of longer nucleic acid fragments of >1 kb. It is compatible with enzymatic reactions and recommended for preparative gel electrophoresis.
- TBE buffer is commonly used with small DNA fragments, as it provides better separation for sizes of <1 kb.
Which electrophoresis buffer is right for you?
| Size of the DNA | Voltage | Use this buffer |
|---|---|---|
| < 1 kb | 5–10 V/cm | TBE |
| 1–5 kb | 4–10 V/cm | TAE or TBE |
| > 5 kb | 1–3 V/cm | TAE |
| Up to 10 kb, fast electrophoresis with Express DNA ladders | Up to 23 V/cm | TAE |