*3.5. Synchronous Fluorescence Spectroscopic Studies*

The microenvironment alterations in the fluorophore residues can be identified with synchronous fluorescence spectroscopy. The changes in emission wavelength indicate polarity change in the fluorophore residue microenvironment [52]. The synchronous spectra recorded at ∆λ = 15 nm and ∆λ = 60 nm provide information about the Tyr and Trp residue microenvironment. The spectra for Tyr showed no shift in the emission wavelength, whereas the spectra for Trp showed a slight 1 nm shift. A blue-shift at ∆λ = 60 nm suggests micro-environmental modifications in the vicinity of Trp residue. Further, it is recommended that the BSA experienced an increased hydrophobicity on interaction with ERL.
