Study of Methylene Blue Interaction with Human Serum Albumin

The thiosine dye methylene blue (MB) interaction with human serum albumin (HSA) has been studied. MB was revealed to stabilize the native structure of HSA, since the denaturation temperature of the complexes is shifted to higher values in relation to that of the pure protein. It was also revealed that the absorption spectra of the complexes do not change noticeably, while in the fluorescence spectra the maximal intensity of MB decreases with the albumin concentration enhancement. Analysis of the obtained data allows to conclude that the main binding mode of MB to HSA, providing the stabilization of the protein native structure, is the electrostatic mechanism.