Controlling tyrosinase activity on charged polyelectrolyte surfaces: a QCM-D analysis.

The quartz crystal microbalance (QCM) was used to monitor the immobilization of tyrosinase on polycationic and polyanionic precursor assemblies in situ and in real-time. The resulting enzymatic surfaces were then exposed to various flavonoids, and the degree of binding was measured using QCM. We show that enzyme activity is retained when immobilized on polycationic films (flavonoid binding observed), while the active site is blocked when assembled on a polyanionic film (no flavonoid binding to the enzyme).