Biochemical Techniques and Instrumentation

Procedure

1. Prepare a 0.8% agarose gel.
2. Add 1 ml of 6X gel loading dye to 2-3 ml of each DNA sample before loading the wells of the gel. Addition of dye allows us to note the extent to which the samples might have migrated during electrophoresis, so that it can be halted at an appropriate stage.
3. Load at least 1 or 2 wells with uncut, good quality λ DNA or any previously quantified DNA samples (50mg and 100mg) as molecular weight standards.
4. Run the submarine electrophoretic gel at 70V till the dye has migrated one-third of the distance in the gel.
5. DNA can be visualized using a UV transilluminator and quantified in comparison with the fluorescent yield of the standards.

Note:

For SSR and RAPD analysis, it is more important to have good quality DNA samples (unsheared/undegraded DNA), than high quantities of DNA. In contrast, RFLP analysis requires larger quantities of DNA, since the technique is not PCR-based.