Light-switching of enzymatic activity on orthognonally functionalized polymer brushes

UV- and visible light-induced switching of enzymatic activity has been demonstrated using surface-grafted polymer brushes functionalized with microperoxidase MP-11 and spiropyran mojeties. The modified samples were integrated into an optofluidic device that allowed the reversible switching of the enzymatic activity for several cycles under flow, validating the potential for application in smart lab-on-a-chip systems.

(a) Strategy for orthogonal functionalization of polymer brushes using specific amine-apoxide and thiol-ene coupling reactions. (b,c) Demonstration of the enzymatic activity and (d,e) of the UV-light induced change in wettability.

Copolymer brushes, composed of glycidyl methacrylate and a furan-protected maleimide-containing monomer, were grafted from radical initiators at the surface of irradiation-activated fluoropolymer foils. After post-polymerization modification with enzymatically active microperoxidase-11 and photochromic spiropyran moieties, the polymer brushes catalyzed the oxidation of 3,3’5,5’-tetramethylbenzidine. Exposure to either UV or visible light allowed switching the turn-over by more than one order of magnitude, as consequence of the reversible, light-induced spiropyran-merocyanine transition.

(a) Schematic illustration of the fabricated optofluidic device integrated with the modified ETFE substrate. (b) Measurement of the enzymatic activity before (orange) and after (purple) exposure to UV light: Three consecutive cycles were measured with 60 minutes relaxation intervals.
Original Publication

Matthias Dübner, Victor J. Cadarso, Tugce N. Gevrek, Amitav Sanyal, Nicholas D. Spencer, and Celestino Padeste
Reversible Light-Switching of Enzymatic Activity on Orthogonally Functionalized Polymer Brushes
ACS Appl. Mater. Interfaces, 2017, 9 (11), pp 9245-9249, 10.1021/acsami.7b01154