Figure 1. IR spectra of native enzyme compared to conjugates. In the figure, from left to right and top to bottom: RrA-chitosan-PEG_30 (30 chains of PEG), RrA-chitosan-glycol, RrA-PEI. The concentration of RrA was 1 mg/ml, chitosan-PEG was 1.5 mg/ml, chitosan-glycol was 0.8 mg/ml, PEI was 0.1 mg/ml. PBS 10 mM, 22°C.