Product Class: Reaction Buffer

Gel Loading Dye, Blue (6X)

Catalog #SizeConcentration
B7021S4 ml


Gel Loading Dye, Blue (6X) is a pre-mixed loading buffer with one tracking dye for agarose and non-denaturing polyacrylamide gel electrophoresis. This solution contains SDS, which often results in sharper bands, as some restriction enzymes are known to remain bound to DNA following cleavage. EDTA is also included to chelate magnesium (up to 10 mM) in enzymatic reactions, thereby stopping the reaction. Bromophenol blue is the standard tracking dye for electrophoresis. It migrates at approximately 300 bp on a standard 1% TBE agarose gel. This product is packaged as 4x1 ml vials.

Properties and Usage

Storage Temperature


1X Buffer Components

1X Buffer Components

2.5% Ficoll®-400
3.3mM Tris-HCl
0.017% SDS
0.015% bromophenol blue
pH 8.0@25°C

Quality Control

Quality Assurance Statement

  • Gel Loading Dye, Blue (6X) is assayed for contaminating endonuclease, exonuclease and RNase activity.

Supporting Documents

The following is a list of Safety Data Sheet (SDS) that apply to this product to help you use it safely.
The Product Summary Sheet, or Data Card, includes details for how to use the product, as well as details of its formulation and quality controls. The following file naming structure is used to name the majority of these document files: [Catalog Number]Datasheet-Lot[Lot Number]. For those product lots not listed below, please contact NEB at or fill out the Technical Support Form for appropriate document.


  1. Use 5 µl of Gel Loading Dye, Blue (6X) per 25 µl reaction, or 10 µl per 50 µl reaction. Mix well before loading gel.
  1. Are Gel Loading Dye, Blue (6x) and Gel Loading Dye Orange (6x) compatible with other systems such as SYBR (add registered mark symbol) and GelRed during gel electrophoresis?
  2. How are the 6x loading dyes packaged?

Usage Guidelines & Tips