JBS Crystal Dyes
Set of JBS Deep Purple, JBS True Blue, JBS Xtal Green and JBS Bright Red
Used to stain macromolecular crystals, i.e. protein, peptide and nucleic acid crystals in order to differentiate them from small molecules and salt crystals.
Crystal dye used to stain macromolecular crystals, i.e. protein, peptide and nucleic acid crystals in order to differentiate them from small molecules and salt crystals.
Description: Crystallization screening with high concentrations of precipitant and salt may lead to the formation of salt crystals. It is quite difficult to make a distinction between these false positives and true protein crystals.
Staining of crystals with appropriate dyes is a very straightforward method to differentiate between macromolecular crystals and salt crystals .
Protein and salt crystals differ substantially in their solvent content. Small crystal dyes, like JBS True Blue, are able to permeate the solvent channels of a protein, thus coloring the protein blue. In contrast, salt crystals are tightly packed and do not possess large solvent channels. They will therefore remain colourless.
 Wilkosz et al. (1995) Preliminary characterization of EcoRI-DNA co-crystals: incomplete factorial design of oligonucleotide sequences. Acta Cryst. D 51:938.