Selective Hydrolysis of Nonactivated Aryl Esters at pH 7 through Cooperative Catalysis

Design Strategy of PepNzymes-SH for an Emerging Catalyst with Serine Hydrolase-Like Functionality

Serine hydrolases, as a class of green catalysts with hydrolytic and dehydrating activities, hold significant application value in the fields of biosynthesis and organic synthesis. However, practical applications face numerous challenges, including maintaining enzyme stability and managing usage costs. PepNzymes-SH, an emerging green catalytic material with enzyme-like activity, overcomes the operational limitations of natural enzymes and holds great promise as a substitute for hydrolases. Unfortunately, a systematic review of the design strategies for PepNzymes-SH is currently lacking. The core significance of this report lies in providing researchers with a comprehensive understanding and theoretical guidance through the summarization and performance evaluation of different design strategies of PepNzymes-SH. This review summarizes strategies for simulating and enhancing the stability of serine hydrolase active sites, oxyanion holes, and hydrophobic environmental structures. By comparing their catalytic activities, we assess the performance changes brought about by different strategies. Furthermore, the applications of PepNzymes-SH in the chemical, biomedicine, and environmental fields are also discussed.

Molecularly Imprinted Nanozymes with Substrate Specificity: Current Strategies and Future Direction

Molecular imprinting technology (MIT) stands out for its exceptional simplicity and customization capabilities and has been widely employed in creating artificial antibodies that can precisely recognize and efficiently capture target molecules. Concurrently, nanozymes have emerged as promising enzyme mimics in the biomedical field, characterized by their remarkable stability, ease of production scalability, robust catalytic activity, and high tunability. Drawing inspiration from natural enzymes, molecularly imprinted nanozymes combine the unique benefits of both MIT and nanozymes, thereby conferring biomimetic catalysts with substrate specificity and catalytic selectivity. In this review, the latest strategies for the fabrication of molecularly imprinted nanozymes, focusing on the use of organic polymers and inorganic nanomaterials are explored. Additionally, cutting-edge techniques for generating atom-layer-imprinted islands with ultra-thin atomic-scale thickness is summarized. Their applications are particularly noteworthy in the fields of catalyst optimization, detection techniques, and therapeutic strategies, where they boost reaction selectivity and efficiency, enable precise identification and quantification of target substances, and enhance therapeutic effectiveness while minimizing adverse effects. Lastly, the prevailing challenges in the field and delineate potential avenues for future progress is encapsulated. This review will foster advancements in artificial enzyme technology and expand its applications.

Design and Synthesis of Metalloporphyrin Nanoconjugates for Dual Light-Responsive Antimicrobial Photodynamic Therapy

Antimicrobial photodynamic therapy (APDT) utilizes photosensitizers (PSs) that eradicate a broad spectrum of bacteria in the presence of light and molecular oxygen. On the other hand, some light sources such as ultraviolet (UVB and UVC) have poor penetration and high cytotoxicity, leading to undesired PDT of the PSs. Herein, we have synthesized conjugatable mesosubstituted porphyrins and extensively characterized them. Time-dependent density functional theory (TD-DFT) calculations revealed that metalloporphyrin EP (5) is a suitable candidate for further applications. Subsequently, the metalloporphyrin was conjugated with lignin-based zinc oxide nanocomposites (ZnOAL and ZnOKL) to develop hydrophilic nanoconjugates (ZnOAL@EP and ZnOKL@EP). Upon dual light (UV + green light) exposure, nanoconjugates showed enhanced singlet oxygen generation ability and also demonstrated pH responsiveness. These nanoconjugates displayed significantly improved APDT efficiency (4-7 fold increase) to treat bacterial infection under dual light irradiation.

Hydrolytic nanozymes: Preparation, properties, and applications

Hydrolytic nanozymes, as promising alternatives to hydrolytic enzymes, can efficiently catalyze the hydrolysis reactions and overcome the operating window limitations of natural enzymes. Moreover, they exhibit several merits such as relatively low cost, easier recovery and reuse, improved operating stability, and adjustable catalytic properties. Consequently, they have found relevance in practical applications such as organic synthesis, chemical weapon degradation, and biosensing. In this review, we highlight recent works addressing the broad topic of the development of hydrolytic nanozymes. We review the preparation, properties, and applications of six types of hydrolytic nanozymes, including AuNP-based nanozymes, polymeric nanozymes, surfactant assemblies, peptide assemblies, metal and metal oxide nanoparticles, and MOFs. Last, we discuss the remaining challenges and future directions. This review will stimulate the development and application of hydrolytic nanozymes.