This work is licensed under Creative Commons Attribution–NonCommercial International License
(CC BY-NC 4.0).
Three-D excitation-emission matrix (EEM) fluorescence spectra of Human Serum Albumin (HSA) were measured at the presence of dimethylsulfoxide (DMSO) at t=25°C during 270 min before and after adding DMSO in different concentrations. It has been shown that DMSO at low concentrations (5%) increase heat-resistance of HSA changing the solvent structure around the protein molecule, it causes conformational changes as well in protein. Drastic changes are observed in the protein struture at DMSO higher concentration (20%). Keywords: human serum albumin, excitation-emission matrix, fluorescence spectroscopy, dimethylsulfoxide, structural changes.