Fig. 1. The free amino group content of glycosylation of BSA treated with different concentrations of urea

Fig. 2. Fluorescence spectra of glycosylation of BSA treated with different concentrations of urea
a→b: 0, 1, 2, 3, 4, 5, 6, 7 mol·L^-1

Fig. 3. The space structure of BSA

Fig. 4. Synchronous fluorescence spectra after glycosylation of BSA in different urea treatments
(a): Δλ=15 nm, (a→b): 1, 2, 3, 0, 4, 5, 6, 7 mol·L^-1; (b): Δλ=60 nm, (a→b): 0, 1, 2, 3, 4, 5, 6, 7 mol·L^-1

Fig. 5. Ultraviolet scanning spectra after glycosylation of BSA in different urea treatments
a→b: 3, 4, 5, 7, 6, 2, 1, 0 mol·L^-1

Fig. 6. 3D fluorescence spectra after glycosylation of BSA and BSA in different urea treatments