Information about DNA loading dye
In 1% agarose gels, bromophenol blue migrates with 300 bp linear double-stranded DNA fragment, whereas xylene cyanol FF migrates at approximately the same rate as linear double-stranded DNA 4 kb length. These relationships are not significantly affected by the concentration (0.5 to 1.4%) of agarose in the gel.
The gel – loading buffer contains only one low concentration dye (bromophenol blue and xylene cyanol FF) to avoid masking the DNA Ladder fragments. But if the added dye is masking your signal because it is running on the same high in your gel, just dilute it more.
The loading dye 306105 siuts well for the enzymatic reaction termination and subsequent loading of DNA samples on the gel for electrophoresis.
How to predilute a DNA ladder with the loading dye?
For DNA markers, apply 0.1 µg per 1 mm of agarose gel lane width. Often 1µg of marker is used in one electrophoresis run but it depends on the size of your gel and the comb.
If DNA markers are not prediluted with the Loading dye solution, then mix: The loading buffer is 10x concentrated, that means you have to use it 10:1.
DNA marker (BIORON 1 kbp with 1 µg/5µl): for example mix 5 µl 1 kb ladder, 1 µl 10x loading dye and 4 µl water. By applying 10.0 µl of this mixture, you’ll have 1.0 µg of total DNA per lane.