Biointerface Photocatalysis: Customized Porous Materials Enabling Synergy between Organic and Inorganic Systems

Conspectus Integrating biological systems with inorganic photocatalysis represents a transformative leap at the nexus of materials science and the life sciences, but it encounters a fundamental incompatibility: highly reactive photogenerated species often deactivate biological components that they are intended to assist. This Account elaborates on our attempts to handle this conflict by moving the design focus from seeking intrinsic catalytic activity to appropriate engineering of interfacial gradients. To achieve biointerface photocatalysis in practice, the electronic and structural properties of inorganic materials must be strictly matched to the specific kinetic constraints of biological targets. We demonstrate that customized porous materials serve as ideal platforms to support functional biointerfaces. This framework centers on the three key functional roles of materials in actively managing the mass, charge, and signal flows. (1) mesoporous confinement acts as a kinetic filter to modulate reactive species evolution and govern mass migration. (2) structural asymmetry generates built-in electric fields to facilitate directed charge movement to specific biological targets. (3) Tailored pore structure defects and surface chemistry regulate the transduction signals and chemical gradients. Leveraging these material-driven functions, we establish bioinorganic synergy across increasing levels of biological complexity. Molecularly, fragile enzymes are spatially isolated via precise mesoporous compartmentalization. This structural mediation efficiently decouples incompatible reaction steps, so that the kinetic gap between slow enzymatic turnover and fast radical production is bridged to facilitate autonomous biocatalytic cascades. Moving to whole-cell microbes’ regulation, our effort moves to active charge management. Asymmetric interfaces and surface defects are engineered to systematically guide photoelectron fluxes into specific microbial transport chains, so we can actively rewire cellular metabolic pathways. Finally, the biointerface could act as a dynamic signal transducer within complex tissue-level models. Physical or chemical triggers are converted to specific physiological signals by combining ultrasound-responsive platforms with functionally gated porous matrices. This methodology enables the precise regulation of tissue microenvironments, ranging from localized redox modulation to logic-gated biosensing. Collectively, these three modes demonstrate how rationally tailored interfacial properties dictate the ultimate functional output of the biohybrid system. However, translating these lab-scale demonstrations into practical technologies requires overcoming formidable challenges like pore fouling, where biofilms or protein corona block mesochannels and reduce system lifespan. Furthermore, conventional evaluation metrics, such as single-site turnover frequency, are inadequate for these highly heterogeneous interfaces. Future development must therefore pivot toward system-level flux metrics and targeted antifouling surface engineering tailored for mesoscale, high-flux scenarios. Through this materials-centric lens, this Account establishes a robust framework for creating stable, efficient, and controllable next-generation biohybrid systems.