Preparation of 6X DNA loading dye (Bromophenol blue, xylene cyanol FF and Sucrose) Alternative method


  • This method uses 40% sucrose solution instead of sucrose powder.
  • This method is convenient and easy, and does not involve adjustment of volume.



  • Bromophenol blue
  • Xylene cyanol FF
  • 40% (W/V) Sucrose solution
  • Deionized / Milli-Q water

Equipment and disposables:

  • Measuring cylinder
  • Conical flask / Beaker / 15 ml screw-capped tube
  • Rotator


  • 0.25% (W/V) bromophenol blue
  • 0.25% (W/V) xylene cyanol FF
  • 40% (W/V) sucrose


Preparation of 10 ml of 6X DNA loading dye containing bromophenol blue, xylene cyanol FF and Sucrose


  • To prepare 10 ml of 6X DNA loading dye, weigh out 25 mg bromophenol blue and 25 mg xylene cyanol FF. Transfer it to screw-capped tube (15 ml with millilitre marks) / beaker / conical flask. Add 10 ml of 40% sucrose solution. Mix until all ingredients are dissolved completely.

Note: This method is simple and convenient as it does not involve readjustment of solution volume. There will not be any significant change in the volume of 40% sucrose solution when you dissolve small amount of  bromophenol blue and xylene cyanol FF in it.

Tips: We recommend to use disposable nuclease nuclease-free (DNase- and RNase-free) 15 ml screw-capped tube with millilitre marks. Transfer all the contents in it. Add 10 ml 40% sucrose solution and mix the content by inverting the tube number of times or using rotator.


  • Store the solution at -20°C for long time. Solution can be stored at 2 – 8°C for few weeks.

Tips: It is recommended to store the solutions in small aliquots (1 ml).

To prepare 6X agarose gel loading dye of various volume (5 ml, 10 ml, 25 ml, 100), follow the table.
Reagents / Volume 5 ml 10 ml 25 ml 50 ml 100 ml
Bromophenol blue 12.5 mg 25 mg 62.5 mg 125 mg 250 mg
Xylene cynol FF 12.5 mg 25 mg 62.5 mg 125 mg 250 mg
40% Sucrose solution 5 ml 10 ml 25 ml 50 ml 100 ml