Figure 10.

(A) Scheme of HRP immobilized via streptavidin-biotin interaction on the chitosan-based U-4CR microgel network, and enzymatic conversion of colorless TMB forming blue-colored, oxidized TMB, a cationic radical. (B) Absorbance measurements investigating the formation of blue-colored TMB by free HRP in solution (black), HRP immobilized on chitosan-based U-4CR microgels (red), and free HRP remaining in solution after the incubation time of the immobilization reaction (blue). In case of the experiments of free and immobilized HRP the initial concentration of the enzyme was 0.05 µM.