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

Resources

Protocols

Visit the Molecular Biology Learning Center

Nucleic acid electrophoresis education