Dual-Mechanism Tuned Engineered Polyphenols with Cascade Photocatalytic Self-Fenton Reaction for Sustainable Biocidal Coatings

Flower like ZnO hybrid mediated visible light harvesting film with upgraded photodynamic antibacterial capacity for effective food preservation

Active food packaging film with light-driven antibacterial properties has inspired numerous interests for food preservation, while efficiently retains the photocatalytic ability remains highly challenging. This study pioneered an advanced visible light-driven photodynamic antibacterial packaging film (FZ-PC) employing an organic-inorganic hybrid strategy, meticulously engineering flower-like zinc oxide functional fillers (FZnO) with superior photoactivity and subsequently formulating a polyvinyl alcohol/sodium carboxymethyl cellulose (PC) mixed film matrix to enhance its physical and chemical properties. The boosting photodynamic activity of the FZnO results from the molecular-level optimization through citral modification. Collectively, the robust electrostatic interactions with bacteria and the enhanced generation capabilities of 1O2, •O2-, and •OH equip the FZ-PC film with superior bacterial inactivation properties, which can reduce the concentrations of Salmonella enteritidis and Staphylococcus aureus by 6 and 6.3 log, respectively. Furthermore, the FZnO-PC film showed lower UV transmittance, higher water contact angle and better mechanical strength. The enhanced antibacterial behavior and improved physicochemical properties of the composite film render it an ideal solution for fruit and vegetable preservation, significantly extending the storage life of cherry tomatoes from 4 days to 11 days. These findings suggest that the developed FZnO-PC film represents a promising advancement in packaging technology.

Photosensitive Oxidase Mimics for Spontaneous and Sustainable Pathogen Disinfection in Personal Protective Equipment

The development of personal protective equipment (PPE) is essential to control the spread of infectious diseases. However, traditional PPE has significant drawbacks, such as a lack of antibacterial capacity and nonreusability, which may result in direct or indirect secondary infections. Herein, we propose an octahedral (Fe-O6) Fe-gallate (Fe-GA) metal-organic framework nanozyme with light-enhanced oxidase-like (OXD-like) activity and extend the use onto nonwoven fabric (Fe-GA/NWF) by hot pressing. Specifically, visible-light-mediated carrier migration and the activity of the OXD-like species synergistically enhance the production of reactive oxygen species, achieving superior antibacterial effects without the addition of any chemical additives. In this case, Fe-GA/NWF spontaneously inactivates over 99.9% of real microbial aerosols and demonstrates excellent mechanical properties, reusability (15 cycles), and biocompatibility. Moreover, Fe-GA/NWF can be used as an ideal antibacterial platform for KN95 masks and protective clothing and can be extended to other substrates. This work provides a promising strategy to develop self-antibacterial PPE in complex environments.

Metal-phenolic networks enhanced the protection of excipients for probiotics during freeze-drying

Probiotic powder using a single protective method during freeze-drying is insufficient vitality because it lacks adequate protection. Here we developed a protection strategy through biointerfacial phenolic self-assembly to enhance the protection of excipients for probiotics to address existing challenges during freeze-drying. This strategy could strengthen the connections of excipients and phenolic protective layers containing hydroxyl groups with water molecules, improving the hydration layer's preservation and shielding bacteria from damage. The results indicated that, compared with origin probiotics, protected probiotics maintained higher viability at approximately 91 % and higher ATPase activity and exhibited a better survival rate in various environmental challenges after freeze-drying. The broad applicability of this protection strategy was confirmed across other LAB strains. Additionally, the protected probiotics demonstrated superior shelf life during 30 days of storage, indicating promising prospects for preparing bacterial powder via freeze-drying.

Recent Advances in Next-Generation Textiles

Textiles have played a pivotal role in human development, evolving from basic fibers into sophisticated, multifunctional materials. Advances in material science, nanotechnology, and electronics have propelled next-generation textiles beyond traditional functionalities, unlocking innovative possibilities for diverse applications. Thermal management textiles incorporate ultralight, ultrathin insulating layers and adaptive cooling technologies, optimizing temperature regulation in dynamic and extreme environments. Moisture management textiles utilize advanced structures for unidirectional transport and breathable membranes, ensuring exceptional comfort in activewear and outdoor gear. Protective textiles exhibit enhanced features, including antimicrobial, antiviral, anti-toxic gas, heat-resistant, and radiation-shielding capabilities, providing high-performance solutions for healthcare, defense, and hazardous industries. Interactive textiles integrate sensors for monitoring physical, chemical, and electrophysiological parameters, enabling real-time data collection and responses to various environmental and user-generated stimuli. Energy textiles leverage triboelectric, piezoelectric, and hygroelectric effects to improve energy harvesting and storage in wearable devices. Luminous display textiles, including electroluminescent and fiber optic systems, enable dynamic visual applications in fashion and communication. These advancements position next-generation textiles at the forefront of materials science, significantly expanding their potential across a wide range of applications.

Bioinspired Assembly of Natural Polyphenol-Amino Acid Surfactants as Multifunctional Durable Coatings for Anticorrosion Fruit Packaging

Challenges emerge in the quest for highly efficient and biocompatible coatings to tackle microbial contamination. Here, we propose a bioinspired paradigm combining (-)-epigallocatechin gallate (EGCG) and l-arginine surfactants (LAM) as all-green building blocks for advanced coatings with superior performance. Molecular dynamics simulations reveal the natural assembly process of the EGCG/LAM supramolecular nanoparticles (ELA NPs). Notably, the coatings retain 99.0% antimicrobial activity even after eight cycles of use and exhibit highly adhesive and anti-water washing properties, maintaining their efficacy after eight uses and 30 days of water soaking on various substrates. When applied as sustainable food packaging coatings for perishable fruits at room temperature, the ELA coatings significantly extend the shelf life of strawberries and cherry tomatoes, reducing weight loss and maintaining firmness and sweetness. This study demonstrates the potential of ELA NPs as versatile and durable coating materials for mitigating food waste and agricultural economic losses due to microbial pollution.

Engineered food-derived hesperetin as heterojunction photosensitizer for inhibiting Staphylococcus aureus and degrading patulin, and its application in perishable strawberries

The potential contamination, including microbial and mycotoxin infection, may escape from the naked eye, posing great threats to food products. Recently, photodynamic inactivation (PDI)-based technology particular has received particular attention because of their high safety. Herein, food-derived hesperetin (Hst) was innovatively introduced as an esculent photosensitizer, engineering with food-grade TiO2 nanoparticles (NPs) to form an organic-inorganic heterojunction structure. Triggered by visible light, the obtained TiO2/Hst NPs were endowed with efficient photoactivity, achieving higher inhibition of Staphylococcus aureus (antibacterial ratio of 98.3 %). The removal capacities of the TiO2/Hst NPs towards patulin (PAT) reached approximately 17.76 μg mg-1, approximately 2 times higher than TiO2 and Hst. The engineered TiO2/Hst NPs were used as the food surface detergent to achieve the ideal inhibition of Staphylococcus aureus and patulin performance on the surface of perishable strawberries, extending the storage life of strawberries.

Unlocking dual-mode enzyme activities on bacterial surface: Directional recognition and swift capture of Alicyclobacillus acidoterrestris from fruit juices

The acidophilic and heat-resistant characteristics of Alicyclobacillus acidoterrestris (A. acidoterrestris) pose significant challenges to fruit juice production. Traditional thermal removal methods are often ineffective against this resilient bacterium. To address this issue, we developed a novel adsorbent, magnetic carbonation carbon-lysozyme nanohybrid (MCL), composed of magnetic nanoparticles with a thin carbon shell and covalently grafted lysozyme. The outer lysozyme facilitates binding to the bacterial surface through two modes: electrostatic attraction and chemical interaction, acting as a vital engine for bacterial adhesion. The ultrathin carbon coating enhances dispersion, reduces magnetic loss, provides more adsorption sites for lysozyme grafting, and ensures stable function in acidic environments. Benefiting from the large surface area of MCL and the specific peptidoglycan recognition structure of lysozyme, MCL exhibits rapid adsorption kinetics and can completely remove 104 CFU/mL of A. acidoterrestris from juice within 20 min. The MCL demonstrates excellent capture performance, negligible cytotoxicity, and no significant impact on juice quality, offering a promising non-thermal strategy to improve juice safety.

Photodynamic inactivation mediated by natural alizarin on bacteria for the safety of fresh-cut apples

Most photosensitizers have limited responsiveness to visible light, however, visible light is a light source with a wide range of wavelengths and the most common in daily life, and making full use of visible light can help to enhance the photodynamic antimicrobial properties of photosensitizers. To tackle this issue, this study confirmed that alizarin has a good absorption capacity for visible light by UV-DRS analysis. Theoretical calculations showed that alizarin might be excited through the charge transfer (CT) mechanism. Under simulated light conditions, alizarin exhibited significant photodynamic inactivation, with a bactericidal efficiency of 99.91 % against S. aureus and L. monocytogenes within 40 min. Meanwhile, the cytolytic rate of alizarin was less than 5 % and the free radical scavenging rate was more than 90 %. To improve the freshness of fresh-cut fruits, we prepared alizarin-pectin (Ali-Pec) coatings using a one-step synthesis method. FT-IR spectroscopic showed the possible presence of hydrogen bonding. It was further found that during storage, the coating-treated fresh-cut apples in the experimental group showed an 8 % reduction in the variation of L-value and a 50 % reduction in the variation of a*-value, and effectively maintained the pH, VC, PPO, and T-AOC levels of the fresh-cut apples, which prolonged the shelf-life of the fresh-cut apples.

Integrated self-assembly and cross-linking technology engineered photodynamic antimicrobial film for efficient preservation of perishable foods

A new antibacterial film was constructed to combat the severe spoilage of fruits and vegetables caused by microorganisms. Specifically, photoresponsive cinnamaldehyde-tannic‑iron acetate nanospheres (CTF NPs) were prepared using ultrasonic-triggered irreversible equilibrium self-assembly and ionic cross-linking co-driven processes and were integrated into the matrix of κ-carrageenan (KC) (CTF-KC films) as functional fillers. The CTF0.4-KC film (KC film doped with 0.4 mg/mL CTF NPs) showed a 99.99% bactericidal rate against both E. coli and S. aureus, extended the storage period of cherry tomatoes from 20 to 32 days. The introduction of CTF enhanced the barrier, thermal stability, and mechanical strength properties, albeit with a slight compromise on transparency. Furthermore, the biosafety of the CTF0.4-KC film was confirmed through hemolysis and cytotoxicity tests. Together, the aforementioned results demonstrated the outstanding antibacterial and fresh-keeping properties of CTF0.4-KC. These desirable properties highlight the potential use of CTF0.4-KC films in food preservation applications.

Metal-phenolic networks spontaneously reinforced carrageenan-based packaging films with antibacterial and antioxidant properties

The burdens of microbial food safety and environmental contamination make it necessary to search sustainable, safe, antibacterial and antioxidant active food packaging materials. This contribution proposed the use of copper-ferulic acid networks (CuFA NWs) as antibacterial substances. By immobilizing CuFA NWs into carrageenan matrix, a CuFA network-reinforced carrageenan-based packaging film (Carr/CuFA) was obtained via spontaneously hydrogen bond and electrostatic interaction indicated by ATR-IR and XPS. Interestingly, the addition of CuFA NWs increased the mechanical strength, surface hydrophobicity, and water vapor barrier properties of the carrageenan-based film, and imparted the film with UV-shielding capacity. Importantly, the Carr/CuFAx film exhibited effective antioxidant activity, and antibacterial performance against four foodborne bacteria. As a result, after confirming the safety of Carr/CuFA3 films by releasing, hemolysis and cell viability experiments, the Carr/CuFA3 film exhibited great potential in the safety control and preservation of fresh fruit by using blueberry and cherry as model fruit. In summary, this work provides a feasible candidate for the preservation and contamination control of fresh fruit.

Chitosan-puerarin composite hydrogel with magnetic enhanced photothermal properties as sustained antimicrobial coatings for beef preservation

The bactericidal properties of traditional food coatings mostly depend on the amount of fungicides present, which reduces the sustainability of food packaging. Herein, we proposed a magnetic field to precisely modulate the near-infrared (NIR) absorption activity to enhance antimicrobial coatings sustainability. Inspired by the typical grinding procedure, the assembly of CP/Fe3O4@TA nanofiber hydrogel was proposed as the coating, applying mechanical force and encouraging the collision of effective molecules of puerarin (PUE), chitosan (CS), and Fe3O4@TA NFs. This hydrogel design offers precise control over the physical and chemical properties, including appearance, viscoelasticity, and rheology. Particularly, significant changes in photothermal performance were observed as a result of magnetic regulation of NIR absorption activity. As a result, the CP/Fe3O4@TA coatings achieve effective bacteria killing performance under NIR irradiation, magnetocaloric effect, boric acid adsorption, and aggregation interference. Finally, the hydrogel coating was applied to the beef surface and serves as an effective barrier against the growth of pathogenic bacteria, thereby preserving the freshness and tenderness of the beef. The finding from this work is expected to open up a new way in active nano hydrogel coating for food preservation.

A covalent-organic framework-based platform for simultaneous smartphone detection and degradation of aflatoxin B1

This study developed a smartphone-based biosensor that could simultaneously detect and degrade aflatoxin B1 (AFB1). A donor-acceptor covalent organic framework (COF) was bound onto the surface of stainless-steel mesh (SSM) via the in-situ synthesis, which was used to immobilize the aptamer (Apt) to specifically capture AFB1 and was also as a photocatalyst to degrade AFB1. Au@Ir nanospheres were synthesized, which exhibited better peroxidase catalytic activity (Km=5.36 × 10-6 M, Vmax=3.48 × 10-7 Ms-1, Kcat=1.00 × 107 s-1) than Ir@Au nanospheres, so Au@Ir nanospheres were linked with Apt2 to be utilized as the signal probe. The density functional theory calculation also described that Au@Ir nanospheres possessed the lower energy barriers to decompose H2O2 than Ir@Au nanospheres. Coupled with the "Color Picker" application in the smartphone, the established "sandwich-structure" colorimetric method exhibited a linear range of 0.5-200 μg L-1 and a detection limit of 0.045 μg L-1. The photocatalytic capacity of SSM/COF towards AFB1 was investigated and the degradation rate researched 81.14 % within 120 min under the xenon lamp irradiation, and the degradation products were validated by ESI-MS. It was applied for the detection of AFB1 in peanuts, corn, and wheat samples. Recoveries were ranging from 77.90 % to 112.5 %, and the matrix effect was 75.10-111.6 %. Therefore, the smartphone-based biosensor provided a simple, fast, and sensitive platform for the detection of AFB1, and meanwhile could realize the efficient degradation of AFB1.

Cu(II)-chelated ovalbumin mimicking the active centre of superoxide dismutase: Structure, antioxidant and antibacterial properties for food preservation application

Enzymatic browning and microbial contamination of food threaten food sensory and safety. With the development of green and healthy concepts, there is a greater need for efficient, low-carbon antioxidant and antimicrobial strategies. In this study, we designed a nano-enzyme with antioxidant activities and biocompatibility. By mimicking the active center of the natural SOD enzyme, copper (Cu) and ovalbumin (OVA) were self-assembled to form Cu-nano-polymerised sheet (Cu-NPS), in which OVA as a scaffold carries cofactors to create the active sites, making the nanoenzymes compatible with the antioxidant activity and antimicrobial properties of Cu, and at the same time possessing good stability and biocompatibility. These properties enable Cu-NPS to have a broader application range, for removing reactive oxygen species (ROS) and broad-spectrum sterilization. Subsequently, Cu-NPS was doped into carrageenan (Carr) to form a nanocomposite film, effectively inhibiting enzymatic browning and microbial contamination. In this work, protein-based mimetic enzymes as artificial nanoenzymes have advantages over natural enzymes, and the Cu-NPS with simple synthesis, high stability, and diverse properties, provides new ideas for the design of functional materials.

Engineering an enzyme-like catalytic sensor for on-site dual-mode evaluation of total antioxidant capacity

A novel Fe-MoOx nanozyme, engineered with enhanced peroxidase (POD)-like activity through strategic doping and the creation of oxygen vacancies, is introduced to catalyze the oxidation of TMB with high efficiency. Furthermore, Fe-MoOx is responsive to single electron transfer (SET) and hydrogen atom transfer (HAT) mechanisms related to antioxidants and can serve as a desirable nanozyme for total antioxidant capacity (TAC) determination. The TAC colorimetric platform can reach a low LOD of 0.512 μM in solution and 24.316 μM in the smartphone-mediated RGB hydrogel (AA as the standard). As proof of concept, the practical application in real samples was explored. The work paves a promising avenue to design diverse nanozymes for visual on-site inspection of food quality.

Electroactive nanofibrous membrane with antibacterial and deodorizing properties for air filtration

Water vapor from respiration can severely accelerate the charge dissipation of the face mask, reducing filtration efficiency. Moreover, the foul odor from prolonged mask wear tends to make people remove their masks, leading to the risk of infection. In this study, an electro-blown spinning electroactive nanofibrous membrane (Zn/CB@PAN) with antibacterial and deodorization properties was prepared by adding zinc (Zn) and carbon black (CB) nanoparticles to the polyacrylonitrile (PAN) nanofibers, respectively. The filtration efficiency of Zn/CB@PAN for PM0.3 was > 99% and could still maintain excellent durability within 4 h in a high-humidity environment (25 ℃ and RH = 95%). Moreover, the bacterial interception rate of the Zn/CB@PAN could reach 99.99%, and it can kill intercepted bacteria. In addition, the deodorization rate of Zn/CB@PAN in the moist state for acetic acid was 93.75% and ammonia was 95.23%, respectively. The excellent filtering, antibacterial, and deodorizing performance of Zn/CB@PAN can be attributed to the synergistic effect of breath-induced Zn/CB galvanic couples' electroactivity, released metal ions, and generated reactive oxygen species. The developed Zn/CB@PAN could capture and kill airborne environmental pathogens under humid environments and deodorize odors from prolonged wear, holding promise for broad applications as personal protective masks.

Organic-Inorganic Heterointerface-Expediting Electron Transfer Realizes Efficient Plasmonic Catalytic Sterilization via a Carbon-Dot Nanozyme

Plasmonic nanozymes bring enticing prospects for catalytic sterilization by leveraging plasmon-engendered hot electrons. However, the interface between plasmons and nanozymes as the mandatory path of hot electrons receives little attention, and the mechanisms of plasmonic nanozymes still remain to be elucidated. Herein, a plasmonic carbon-dot nanozyme (FeCG) is developed by electrostatically assembling catalytic iron-doped carbon dots (Fe-CDs) with plasmonic gold nanorods. The energy harvesting and hot-electron migration are remarkably expedited by a spontaneous organic-inorganic heterointerface holding a Fermi level-induced interfacial electric field. The accumulated hot electrons are then fully utilized by conductive Fe-CDs to boost enzymatic catalysis toward overproduced reactive oxygen species. By synergizing with localized heating from hot-electron decay, FeCG achieves rapid and potent disinfection with an antibacterial efficiency of 99.6% on Escherichia coli within 5 min and is also effective (94.2%) against Staphylococcus aureus. Our work presents crucial insights into the organic-inorganic heterointerface in advanced plasmonic biocidal nanozymes.

Enzyme-triggered on-demand release of a H2O2-self-supplying CuO2@Fe3O4 nanoagent for enhanced chemodyamic antimicrobial therapy and wound healing

Nanoagents for chemodynamic therapy (CDT) hold a promising future in the field of antimicrobials, especially copper peroxide (CuO2) (CP) nanomaterials which have garnered significant attention due to their ability to self-supply H2O2. Nevertheless, the poor stability of CuO2 remains a critical challenge which restricts its practical application in the antibacterial field. In this study, an advanced nano-antimicrobial system HA-CP@Fe3O4 with enzyme-responsive properties is developed by coating hyaluronic acid (HA) on CuO2-loaded iron tetraoxide nanoparticles. The coating of HA not only stabilizes the CuO2 nanomaterials but also provides responsiveness towards the enzyme hyaluronidase, which is typically secreted by some bacteria. The outer layer of HA in HA-CP@Fe3O4 undergoes decomposition in the presence of hyaluronidase-secreting bacteria, resulting in the release of CuO2@Fe3O4. The released CuO2@Fe3O4 then self-supplies H2O2 and generates reactive oxygen species (ROS) within the infected microenvironment through Fenton and Russell effects, to ultimately achieve effective and precise antimicrobial activity. Simultaneously, the magnetic property provided by Fe3O4 allows the substance to be directed towards the infection site. Both in vitro and in vivo tests demonstrated that HA-CP@Fe3O4 exhibited excellent antimicrobial capabilities at low concentration (30 μg mL-1), exceptional biocompatibility and the ability to accelerate wound healing. The findings of this work offer a new and promising approach for targeted and precise CDT.

Clinically Approved Ferric Maltol: A Potent Nanozyme with Added Effect for High-Efficient Catalytic Disinfection

Nanozyme has been proven to be an attractive and promising candidate to alleviate the current pressing medical problems. However, the unknown clinical safety and limited function beyond the catalysis of the most reported nanozymes cannot promise an ideal therapeutic outcome in further clinical application. Herein, we find that ferric maltol (FM), a clinically approved iron supplement synthesized through a facile scalable method, exhibits excellent peroxidase-like activity than natural horseradish peroxidase-like (HRP) and commonly reported Fe-based nanozymes, and also shows high antibacterial performance for methicillin-resistant Staphylococcus aureus (MRSA) elimination (100%) and wound disinfection. In addition, with added effects inherited from contained maltol, FM can accelerate skin barrier recovery. Therefore, the exploration of FM as a safe and desired nanozyme provides a timely alternative to current antibiotic therapy against drug-resistant bacteria.

Dual-Readout Ultrasensitive Lateral Flow Immunosensing of Salmonella typhimurium in Dairy Products by Doping Engineering-Powered Nanoheterostructure with Enhanced Photothermal Performance

The photothermal lateral flow immunoassay (LFIA) is of great significance to suitable for on-site semiquantitative detection, which has the upper hand in further constructing detection methods for low-concentration targets. Herein, we presented a doping engineering-powered nanoheterostructure with an enhanced photothermal performance strategy, employing bimetallic nanocuboid Pt3Sn (PSNCs) as a proof of concept. With the help of finite element simulation analysis, the contrast of direct temperature experiment, and the evaluation of photothermal conversion efficiency (η), the distinguished and enthusiastic photothermal feedback of PSNCs is proved. Based on steady bright black of colorimetric and superior photothermal performance, the PSNCs were employed to construct an ultrasensitive model LIFA for detecting Salmonella typhimurium (S. typhimurium), which achieved the double-signal semiquantitative detection, the detection limit reached 103 cfu mL-1 (colorimetric mode) and 102 cfu mL-1 (photothermal mode), which is 100 times higher than that of the traditional colloidal gold method. In addition, the method was effective for the detection of targets in dairy samples only through a simple dilution treatment, which was completed within 15 min. Meanwhile, this PSNCs dual-signal LFIA demonstrated the sensitive detection of S. typhimurium due to the excellent colorimetric signal and significant photothermal performance, which provides a broad spectrum for the future detection of foodborne pathogens.

Thermal-Driven Curcumin Release Film with Dual-Mode Synergistic Antibacterial Behavior for Efficient Tangerine Preservation

Antimicrobial packing showed great potential in extending the shelf life of food. However, developing a new biocomposite film with an intelligent and efficient antimicrobial performance is still desirable. Herein, a Fe-MoOx encapsulated with curcumin (Cur) filled chitosan-based composite film (CCF films) was prepared by solvent casting method. The total color differences of the CCF films were less than 30%, and satisfactory surface color, transparency, hydrophobicity, and thermal stability were also obtained. Besides, the UV-light/water/oxygen barrier capability and mechanical properties were enhanced with the incorporation of Cur@Fe-MoOx. Moreover, CCF films showed photothermal performance and thermal-controlled curcumin release ability, which endowed the CCF0.15 film with excellent antibacterial capability toward E. coli (≥99.95%) and S. aureus (≥99.96%) due to the synergistic antibacterial effect. Fe-MoOx exhibited high cell viability and less than 5% hemolysis even under the concentration of 500 μg mL-1. Based on those unique characteristics, the CCF0.15 film was chosen for tangerine preservation. The CCF0.15 film could prolong the shelf life of tangerine by at least 9 days compared with the unpacking group, and the tangerines could maintain the freshness characteristics over a 24 day storage period. Such thermal-mediated antibacterial film proposed by our work showed promising potential in food packaging.