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With the rapid growth in global food production, delivery, and consumption, reformative food analytical techniques are required to satisfy the monitoring requirements of speed and high sensitivity. Nanozyme‐encoded luminescent detections (NLDs) integrating nanozyme‐based rapid detections with luminescent output signals have emerged as powerful methods for food safety monitoring, not only because of their preeminent performance in analysis, such as rapid, facile, low background signal, and ultrasensitive, but also due to their strong attractiveness for future sensing research. However, the lack of a full understanding of the fundamentals of NLDs for food safety detection technologies limits their further application. In this review, a systematic overview of the mechanisms of NLDs and their applications in the food industry is summarized, which covers the nanozyme‐mimicking types and their luminescent signal generation mechanisms, as well as their applications in monitoring common foodborne contaminants. As demonstrated by previous studies, NLDs are bridging the gap to practical‐oriented food analytical technologies and various opportunities to improve their food analytical performance to be considered in the future are proposed. [ABSTRACT FROM AUTHOR]

The public concerns about agrifood safety call for innovative and reformative analytical techniques to meet the inspection requirements of high sensitivity, specificity, and reproducibility. Enzyme‐mimetic nanomaterials or nanozymes, which combine enzyme‐like properties with nanoscale features, emerge as an excellent tool for quality and safety detection in the agrifood sector, due to not only their robust capacity in detection but also their attraction in future‐oriented exploitations. However, in‐depth understanding about the fundamental principles of nanozymes for food quality and safety detection remains limited, which makes their applications largely empirical. This review provides a comprehensive overview of the principles, designs, and applications of nanozyme‐based detection technique in the agrifood industry. The discussion mainly involves three mimicking types, that is, peroxidase, oxidase, and catalase‐like nanozymes, capable of detecting major agrifood analytes. The current principles and strategies are classified and then discussed in details through discriminating the roles of nanozymes in diverse detection platforms. Thereafter, recent applications of nanozymes in detecting various endogenous ingredients and exogenous contaminants in foods are reviewed, and the outlook of profound developments are explained. Evidenced by the increasing publications, nanozyme‐based detection techniques are narrowing the gap to practical‐oriented food analytical methods, while some challenges in optimization of nanozymes, diversification of recognition‐to‐signal manners, and sustainability of methodology need to conquer in the future. [ABSTRACT FROM AUTHOR]

An isoreticular principle guides the directed evolution of domino reactions in MOF nanozymes against antibacterial resistance. The Ce-UiO-66 nanozymes, with linker-dependency on dual hydrolytic and redox mimicry, couple ATP depletion and ROS generation into a unique biofilm microenvironment-responsive prodrug-mimicking domino reaction, enabling the kinetically favourable Ce-UiO-66-NO 2 to effectively target and inhibit MRSA biofilm at the initial bacterial adhesion stage. [Display omitted] • Isoreticular chemistry accelerates the directed nanozyme discovery of Ce-MOFs. • Linker dependence Ce-UiO-66-X modulates dual apyrase and oxidase biomimicry; • Domino effect of the hydrolytic and redox activities in Ce-UiO-66-X is revealed; • Domino reaction in Ce-UiO-66-X couples ATP hydrolysis and ROS generation; • Ce-UiO-66-X enables microenvironment-responsive disinfection of MRSA biofilm. Nanozyme therapy holds promise for overcoming daunting antimicrobial resistance, but skills to target the microbial microenvironment are lacking. Herein, an isoreticular principle was introduced in nanozyme discovery to directedly evolve a domino biomimetic reaction specific to drug-resistant bacterial biofilm. The isoreticular Ce-UiO-66-X (X = BDC, BDC-CH 3 , BDC-OH, BDC-NH 2 , BDC-NO 2 , ADC, Fum) MOFs exhibited linker-dependent mimicry of hydrolytic apyrase and redox oxidase, and the phosphorous reactants (ATP/ADP/AMP/Pi) produced by the ATP hydrolysis could spontaneously activate redox reaction in Ce-UiO-66-X. Evidenced by the representative Ce-BDC-X (X = –NO 2 , -H, and –NH 2) nanozymes, the unique domino reaction of Ce-UiO-66-X could simultaneously deplete ATP molecules and trigger enhanced generation of superoxide radicals at the specific time window in the initial bacterial adhesion stage of methicillin-resistant Staphylococcus aureus (MRSA) biofilm formation. Due to the synergistic nanocatalytic mechanism, possible nanoscale penetration effect, and good biocompatibility, Ce-UiO-66-NO 2 could effectively target and destroy the metabolic microenvironment of MRSA biofilm in vitro and in vivo, reducing the MRSA biofilm viability to as low as 3.64%. This work demonstrates a new prodrug-like enzymodynamic antibacterial therapeutics based on cooperative multienzyme reactivity. [ABSTRACT FROM AUTHOR]

Nanozyme technique with efficient modulating strategies is a promising tool for biocatalytic and biosensing applications, yet insights into target-responsive controllability of oxidase nanozymes remain largely unknown. In this contribution, we report a state-of-art oxidase-like and ssDNA-tunable nanozyme for biomolecular recognition. In detail, the spinel-type manganese cation substituted cobalt oxide (MnCo 2 O 4 ) submicrospheres can imitate oxidase for efficiently catalytic oxidation of colorimetric substrate, superior to current metal oxide-based oxidase nanozymes. More importantly, the nanozyme activity of spinel MnCo 2 O 4 can be reversibly inhibited by the attachment/detachment of aptamer strands on MnCo 2 O 4 surface via the aptamer-target binding event, enabling a new colorimetric access for detecting biomolecules. Taking highly toxic ochratoxin A (OTA) as model molecule, we can selectively determine OTA in maize samples with a limit of detection (3δ/ S ) of 0.08 ng/mL. The unique nanozyme property of spinel MnCo 2 O 4 , together with the principle of our approach, reveals the potential of ssDNA-tailorable oxidase nanozymes in biocatalytic and biosensing fields. [ABSTRACT FROM AUTHOR]

The growing concerns about microbial food safety and environmental contamination call for sustainable food active packaging materials and practices with high performance. This contribution proposed a biocatalytic spraying coating for fruit preservation using carboxymethyl cellulose nanofibers grafting enzyme-like metal-organic frameworks (CNF@Ce-MOF) with banana and mango as model fruits. The well-characterized biohybrid nanofibers were verified to simultaneously mimic good oxidase-like and apyrase-like activities, enabling effective enzyme-like sterilization against three typical foodborne pathogens, i.e. Escherichia coli O157: H7, Staphylococcus aureus , and methicillin-resistant Staphylococcus aureus , reaching killing rates as high as 90.46%. The biocidal •O 2 − generation and adenosine triphosphate depletion were the possible mechanisms causing the nonspecific bacteria death. Such antibacterial performance, as well as additional protective properties of CNF@Ce-MOF, facilitated the quality preservation during the 12-day storage of bananas and mangos by spray coating with the biomimetic CNF@Ce-MOF. It is expected that this work walks out the first step of nanozyme toward active packaging engineering for the fields of food, agriculture, and biomedicine. [Display omitted] • Biopolymeric nanozyme was created by biomineralizing in situ MOF on nanocellulose. • Dual enzyme biomimicry by CNF@MOF produced.•O 2 − species and depleted ATP • CNF@MOF possessed bacteriostatic activities, UV resistance and biocompatibility. • Pioneering research was conducted by introducing nanozyme into active packaging. • CNF@MOF coating improved quality and extended shelf life of banana and mango. [ABSTRACT FROM AUTHOR]

The grave threat posed by food hazards to food security and human health has increased the urgency of rapid and sensitive detection. Enzyme-mimic immune detection, particularly nanozyme-activated food immunosensors (NAFI), shows distinct specificity and catalytic properties, advancing food safety supervision. However, knowledge of the fundamental principles and functionalities of NAFI is still limited. Based on tracking the timeline of the independent evolution and combination of immunosensors and nanozymes, we first provide a systemic view to describe the trends of NAFI. Moreover, the underlying catalytic mechanisms are discussed according to classification in this review, including metal-based, carbon-based, and metal-organic framework-based nanozymes. In particular, significant attention is focused on the fundamental function of nanozyme receptors in food immunosensors, including the connection between nanozymes and bio-affinity ligands (one pot and two steps), signal modulation and amplification, and various signal outputs (typical and novel modes), which are crucial for gaining the best performance and further innovation. Finally, based on representative applications of nanozymes to detect food hazards, the main challenges in the development of NAFI are summarized, and future research directions for this highly prospective frontier are envisioned. • Nanozyme-activated food immunosensors (NAFI) are systematically discussed. • The history, category, and mechanism of NAFI are summarized. • Strategies for balancing nanozyme and antibody activities are summarized. • Both the typical signal mode and innovative signal mode are evaluated. • A perspective on the future trajectory of NAFI is provided. [ABSTRACT FROM AUTHOR]