TCA precipitation of dansylated proteins

TCA precipitation of dansylated proteins

Precipitated proteins after THF wash
Numbers are micrograms of protein

Dissolved in 100 microliters 0.1% SDS, 50mM Tris
Photographed through Tiffen Green 11 and 520nm long pass filters

Useful observations

The dansylated proteins contained crystal violet which stained the TCA precipitate improving it's visibility. It's worth adding routinely. The dansylated proteins were not visible by fluorescence in the initial pellet and became visible only when sarkosyl was removed by the THF wash. THF evaporates easily on standing.

Adding base (Tris) to the SDS was necessary to solubilize the protein. Presumably (much) small amounts of Tris will suffice.