Enzymatic Catalysis Combining the Breath Figures and Layer-by-Layer Techniques: Toward the Design of Microreactors

Herein, we report the fabrication of microstructured porous surfaces with controlled,enzymatic activity by combining the breath figures and the layer-by-layer techniques. Two different types of porous surfaces were designed based on fluorinated and carboxylated copolymers in combination with PS, using poly(2,3,4,5,6-pentafluorostyrene)-b-polystyrene (PS5F(31)-b-PS21) and polystyrene-b-poly(acrylic acid) (PS19-b-PAA(10)) block copolymers, respectively. For comparative purposes, flat surfaces having similar chemistry were obtained by spin-coating. Poly(sodium 4-styrenesulfonate)/poly(allylamine hydrochloride) (PSS/PAH) multilayers incorporating alkaline phosphatase (ALP) were built on these porous surfaces to localize the enzyme both inside and outside of the pores using PS/PS5F(31)-b-PS21 surfaces and only inside the pores on PS/PS19-b-PAA(10) surfaces. A higher catalytic activity of ALP (about three times) was obtained with porous surfaces compared to the flat ones. The catalysis happens specifically inside the holes of PS/PS19-b-PAA(10)surfaces, where ALP is located. This opens the route for applications in microreactors.