There are several dyes (Bromophenol blue, Bromocresol green, Orange G, Xylene cyanol FF) that can be used for the preparation of DNA loading dye/buffer.
An ideal dye, used for the preparation of DNA loading dye/buffer, should have the following characteristics.
- It should not interact with the DNA or component of electrophoresis buffer and gel.
- Like DNA, It should have a negative charge and move towards the positive pole.
- It should impart contrast color to DNA samples and its migration should easily be monitored visually.
- It should not interfere with the analysis of DNA.
- The size of the dye must be within the upper and lower resolution limit of the agarose gel (50 bp to 20 KB)