New hydrophobic intramolecular charge transfer probes, comprising an aminostyryl and a cyanopyranyl moieties, were developed for sensitive protein quantification in solution. The probes exhibited dramatic increase of fluorescence quantum yields with accompanying blue-shift of the emission when bound to protein-sodium dodecyl sulfate (SDS) complexes. Using this emission enhancement, the synthesized probes were successfully applied for determining protein concentrations in solution.