Electrospray mass spectrometry: Complexation between 1-anilinonaphthalene-8-sulphonate and proteins

Complexation of the hydrophobic fluorescent dye 1-anilinonaphthalene-8-sulphonate with a number of proteins was examined by electrospray ionization mass spectrometry (ESMS). The apparent agreement between the present data and those obtained by fluorescence spectroscopy underlines the role of ESMS in the overall approach to protein folding and unfolding.