The 2000 bp DNA Marker is a DNA solution containing 1X loading buffer, allowing direct electrophoresis by loading 5 µL. This ladder consists of the following DNA fragments: 2000 bp, 1000 bp, 750 bp, 500 bp, 250 bp, and 100 bp. The 750 bp band contains approximately 100 ng DNA, while all other bands contain approximately 50 ng DNA each.

1. If the sample well is less than 6 mm wide, load 5 µL of the marker to obtain clear bands. For wider wells, increase the loading volume accordingly.
2. For DNA electrophoresis, the purity of agarose greatly affects band clarity. Use high-quality agarose when possible.
3. The agarose concentration strongly influences DNA fragment separation: higher concentrations improve resolution of shorter fragments, while lower concentrations improve resolution of longer fragments.
4. Avoid using excessively high voltages; keep the voltage around 5 V/cm. Use freshly prepared electrophoresis buffer, especially when preparing reference gel images.