Figure 3. Gel staining using Lettuce.

a) Titration of Lettuce on a gel. To test the amount required to visualize Lettuce on a gel, we prepared samples containing known amounts of Lettuce. The amount of Lettuce specified was loaded into each lane of a 10% TBE-urea polyacrylamide gel. After polyacrylamide gel electrophoresis, the gel was washed to remove urea, and then stained with DFHBI-1T (20μM) in a solution containing 140 mM KCl and 1 mM MgCl₂. Fluorescence was measured using the FITC protocol in a Bio-Rad gel doc imager. b) Lettuce can be observed on a gel in a mix of other DNA with DFHBI-1T staining. The gel was also stained with SYBR-Gold (right) to observe total DNA. Samples were prepared with Lettuce (2 pmol) and sheared salmon sperm DNA (“+” corresponds to 8 μg, “++” corresponds to 40 μg). Samples were loaded into a 10% TBE-urea polyacrylamide gel. After polyacrylamide gel electrophoresis, the gel was stained with DFHBI-1T (20 μM) or SYBR Gold in a solution containing 140 mM KCl and 1 mM MgCl₂. Fluorescence was measured using the FITC imaging channel in a Bio-Rad gel doc imager.