Construction of Metal-Organic Framework-Based Heterogeneous Pepsin and Its Degradation Performance and Mechanism for Phthalic Acid Esters.

Biological enzyme-driven degradation of environmental pollutants has attracted widespread attention because it is ecofriendly and highly efficient. Immobilized enzyme technology has emerged as a promising technique in enzymology that addresses the limitations associated with free enzymes. Traditional solid-loaded enzyme substrates are often affected by blockages and restricted substrate accessibility. In this study, we synthesized an efficient heterogeneous pepsin catalyst, named PEP@M-MIL100(Fe), by covalently combining carboxylated ferrite structural expanded metal-organic frameworks with pepsin. This catalyst demonstrated excellent environmental adaptability and remarkable catalytic degradation capabilities. Notably, it rapidly degraded the persistent microplastic pollutant diisononyl phthalate (DINP) within just 150 min, with a removal efficiency of up to 95.88%. Impressively, even after 10 consecutive uses, the catalyst maintained its high performance. We proposed an innovative steady-state heterogeneous enzyme-catalyzed degradation mechanism, i.e., diffusion (D)-absorption (A)-binding (B)-reaction (R)-degradation (D)-link mechanism, which emphasizes the influence of substrate diffusion rates in this process. This work presents the first successful application of pepsin to DINP degradation and offers a sustainable and effective approach for addressing contemporary pollution challenges.

Spectrally engineered textile for radiative cooling against urban heat islands.

Radiative cooling textiles hold promise for achieving personal thermal comfort under increasing global temperature. However, urban areas have heat island effects that largely diminish the effectiveness of cooling textiles as wearable fabrics because they absorb emitted radiation from the ground and nearby buildings. We developed a mid-infrared spectrally selective hierarchical fabric (SSHF) with emissivity greatly dominant in the atmospheric transmission window through molecular design, minimizing the net heat gain from the surroundings. The SSHF features a high solar spectrum reflectivity of 0.97 owing to strong Mie scattering from the nano-micro hybrid fibrous structure. The SSHF is 2.3°C cooler than a solar-reflecting broadband emitter when placed vertically in simulated outdoor urban scenarios during the day and also has excellent wearable properties.

Identifying critical features of iron phosphate particle for lithium preference.

One-dimensional (1D) olivine iron phosphate (FePO4) is widely proposed for electrochemical lithium (Li) extraction from dilute water sources, however, significant variations in Li selectivity were observed for particles with different physical attributes. Understanding how particle features influence Li and sodium (Na) co-intercalation is crucial for system design and enhancing Li selectivity. Here, we investigate a series of FePO4 particles with various features and revealed the importance of harnessing kinetic and chemo-mechanical barrier difference between lithiation and sodiation to promote selectivity. The thermodynamic preference of FePO4 provides baseline of selectivity while the particle features are critical to induce different kinetic pathways and barriers, resulting in different Li to Na selectivity from 6.2 × 102 to 2.3 × 104. Importantly, we categorize the FePO4 particles into two groups based on their distinctly paired phase evolutions upon lithiation and sodiation, and generate quantitative correlation maps among Li preference, morphological features, and electrochemical properties. By selecting FePO4 particles with specific features, we demonstrate fast (636 mA/g) Li extraction from a high Li source (1: 100 Li to Na) with (96.6 ± 0.2)% purity, and high selectivity (2.3 × 104) from a low Li source (1: 1000 Li to Na) with (95.8 ± 0.3)% purity in a single step.

Unveiling the mechanism of photothermal therapy in acne man-agement: targeting sebaceous gland ferroptosis via umbilical cord mesenchymal stem cell membrane-encapsulated Au-Ag-PDA.

Background: Branched gold and silver nanoparticles coated with polydopamine (Au-Ag-PDA) demonstrate high photothermal conversion efficiency. Utilizing umbilical cord mesenchymal stem cell membranes (MSCM) as an effective drug delivery system, our preliminary studies investigated the suppression of sebum secretion in sebaceous glands using MSCM-coated Au-Ag-PDA nano-particles (Au-Ag-PDA@MSCM) combined with 808 nm laser irradiation, showing potential for dermatological applications in acne treatment. Methods: This study employs proteomic analysis, complemented by subsequent techniques such as Western blotting (WB), small interfering RNA (siRNA), and transmission electron microscopy, to further investigate the differential mechanisms by which Au-Ag-PDA and Au-Ag-PDA@MSCM-mediated photothermal therapy (PTT) suppress sebum secretion. Results: Our proteomic analysis indicated mitochondrial respiratory chain damage in sebaceous gland tissues post-PTT, with further validation revealing ferroptosis in sebaceous cells and tissues. Acyl-CoA Synthetase Long-Chain Family Member 4 (Acsl4) has been identified as a critical target, with Au-Ag-PDA@MSCM demonstrating enhanced ferroptotic effects. Conclusion: These findings significantly advance our understanding of how PTT mediated by Au-Ag-PDA@MSCM nanoparticles reduces sebum secretion and underscore the pivotal role of MSCM in inducing ferroptosis in sebaceous glands, thus providing a robust theoretical foundation for employing PTT via specific molecular pathways in acne treatment.

Uncovering the predictive pathways of lithium and sodium interchange in layered oxides.

Ion exchange is a powerful method to access metastable materials with advanced functionalities for energy storage applications. However, high concentrations and unfavourably large excesses of lithium are always used for synthesizing lithium cathodes from parent sodium material, and the reaction pathways remain elusive. Here, using layered oxides as model materials, we demonstrate that vacancy level and its corresponding lithium preference are critical in determining the accessible and inaccessible ion exchange pathways. Taking advantage of the strong lithium preference at the right vacancy level, we establish predictive compositional and structural evolution at extremely dilute and low excess lithium based on the phase equilibrium between Li0.94CoO2 and Na0.48CoO2. Such phase separation behaviour is general in both surface reaction-limited and diffusion-limited exchange conditions and is accomplished with the charge redistribution on transition metals. Guided by this understanding, we demonstrate the synthesis of NayCoO2 from the parent LixCoO2 and the synthesis of Li0.94CoO2 from NayCoO2 at 1-1,000 Li/Na (molar ratio) with an electrochemical assisted ion exchange method by mitigating the kinetic barriers. Our study opens new opportunities for ion exchange in predictive synthesis and separation applications.

Programmable and Pixelated Solute Concentration Fields Controlled by Three-Dimensionally Networked Microfluidic Source/Sink Arrays.

Membrane-integrated microfluidic platforms have played a pivotal role in understanding natural phenomena coupled with solute concentration gradients at the micro- and nanoscale, enabling on-chip microscopy in well-defined planar concentration fields. However, the standardized two-dimensional fabrication schemes in microfluidics have impeded the realization of more complex and diverse chemical environmental conditions due to the limited possible arrangements of source/sink conditions in a fluidic domain. In this study, we present a microfluidic platform with a three-dimensional microchannel network design, where discretized membranes can be integrated and individually controlled in a two-dimensional array format at any location within the entire quasi-two-dimensional solute concentration field. We elucidate the principles of the device to implement operations of the pixel-like sources/sinks and dynamically programmable control of various long-lasting solute concentration fields. Furthermore, we demonstrate the application of the generated solute concentration fields in manipulating the transport of micrometer or submicrometer particles with a high degree of freedom, surpassing conventionally available solute concentration fields. This work provides an experimental tool for investigating complex systems under high-order chemical environmental conditions, thereby facilitating the extensive development of higher-performance micro- and nanotechnologies.

Dendrimer-conjugated isotretinoin for controlled transdermal drug delivery.

BACKGROUND: In the present study, we aimed to develop a novel isotretinoin delivery model for treating skin diseases, revealing its potential advantages in drug delivery and targeted therapy. Using a self-assembly strategy, we grafted a dendrimer, based on a well-defined branched structure for nanomedical devices, with a well-defined nanoarchitecture, yielding spherical, highly homogeneous molecules with multiple surface functionalities. Accordingly, a self-assembled dendrimer-conjugated system was developed to achieve the transdermal delivery of isotretinoin (13cRA-D). RESULTS: Herein, 13cRA-D showed remarkable controlled release, characterized by slow release in normal tissues but accelerated release in tissues with low pH, such as sites of inflammation. These release characteristics could abrogate the nonteratogenic side effects of isotretinoin and allow efficient skin permeation. Moreover, 13cRA-D exhibited high therapeutic efficacy in acne models. Based on in vitro and in vivo experimental results, 13cRA-D afforded better skin penetration than isotretinoin and allowed lesion targeting. Additionally, 13cRA-D induced minimal skin irritation. CONCLUSION: Our findings suggest that 13cRA-D is a safe and effective isotretinoin formulation for treating patients with skin disorders.

Imaging supermolecular interactions of the pharmaceutical-cocrystal of apigenin-nicotinamide binding with serum albumin.

In this paper, a new pharmaceutical cocrystal was synthesized using apigenin (AP) and pharmaceutically acceptable conformer nicotinamide (Nico), and the drug delivery between AP-Nico pharmaceutical cocrystal and human serum albumin (HSA) in vivo was studied at atomic scale. The pharmaceutical cocrystal was characterized using Fourier-transform infrared (FTIR) spectroscopy, 1H NMR spectroscopy, differential scanning calorimetry (DSC), and powder X-ray diffraction (PXRD), and the self-assembling mechanism was explored. The dissolution and cumulative release in vitro were investigated. Molecular dynamic (MD) simulation combined with fluorescence spectroscopy was used to study the delivery mechanism of AP-Nico to HSA. The results showed that AP was pharmaceutically cocrystallized with Nico, which formed a pharmaceutical cocrystal mainly through hydrogen interaction between the -OH groups of AP and -NH2 groups of Nico. The solubility of the AP-Nico was 3 times higher than raw AP and the cumulative release rate was 71%. The fluorescence spectroscopy results showed that the AP-Nico pharmaceutical cocrystal bind with Sudlow's site I inside the HSA molecule with hydrogen-bond interaction as the main force. The Sudlow's site I of HSA conjugated with AP-Nico explains the conformational changes of HSA in-silico. This study provided a useful reference for synthesizing flavonoid pharmaceutical cocrystal to improve solubility and exploring the interaction mechanism while understanding its delivery mechanism in vivo.

A Scalable Microstructure Photonic Coating Fabricated by Roll-to-Roll "Defects" for Daytime Subambient Passive Radiative Cooling.

The deep space's coldness (∼4 K) provides a ubiquitous and inexhaustible thermodynamic resource to suppress the cooling energy consumption. However, it is nontrivial to achieve subambient radiative cooling during daytime under strong direct sunlight, which requires rational and delicate photonic design for simultaneous high solar reflectivity (>94%) and thermal emissivity. A great challenge arises when trying to meet such strict photonic microstructure requirements while maintaining manufacturing scalability. Herein, we demonstrate a rapid, low-cost, template-free roll-to-roll method to fabricate spike microstructured photonic nanocomposite coatings with Al2O3 and TiO2 nanoparticles embedded that possess 96.0% of solar reflectivity and 97.0% of thermal emissivity. When facing direct sunlight in the spring of Chicago (average 699 W/m2 solar intensity), the coatings show a radiative cooling power of 39.1 W/m2. Combined with the coatings' superhydrophobic and contamination resistance merits, the potential 14.4% cooling energy-saving capability is numerically demonstrated across the United States.

Fabricating and Laminating Films with Through-Holes and Engraved/Protruding Structures for 3D Micro/Nanofluidic Platforms.

Micro/nanofluidic devices have become popular for delicately processing biological, material, and chemical samples. However, their reliance on 2D fabrication schemes has hindered further innovation. Here, a 3D manufacturing method is proposed through the innovation of laminated object manufacturing (LOM), which involves the selection of building materials as well as the development of molding and lamination techniques. Fabrication of interlayer films is demonstrated with both multi-layered micro-/nanostructures and through-holes, using an injection molding approach and establishing strategic principles of film design. Utilization of the multi-layered through-hole films in LOM allows reducing the number of alignments and laminations by at least two times compared to conventional LOM. Using a dual-curing resin for film fabrication, a surface-treatment-free and collapse-free lamination technique is shown for constructing 3D multiscale micro/nanofluidic devices with ultralow aspect ratio nanochannels. The 3D manufacturing method enables the development of a nanochannel-based attoliter droplet generator capable of 3D parallelization for mass production, which implies the remarkable potential to extend numerous existing 2D micro/nanofluidic platforms into a 3D framework.

Minoxidil delivered via a stem cell membrane delivery controlled release system promotes hair growth in C57BL/6J mice.

Objective: Umbilical cord-derived mesenchymal stem cell membrane-loaded minoxidil (MXD) nanoparticles (STCM-MXD-NPs) were prepared to investigate their effects on hair growth in C57BL/6J mice. Methods: STCM-MXD-NPs were obtained by freeze-thawing and differential centrifugation, and their effects on hair growth were evaluated using C57BL/6J mice. The mRNA and protein expression levels of vascular endothelial growth factor (VEGF) and insulin-like growth factor-1 (IGF-1) were detected by real-time polymerase chain reaction and enzyme-linked immunosorbent assays, respectively. Protein expression levels of marker of proliferation Ki-67 (MKI67) and ß-catenin (CTNNB) in skin tissue were detected by immunohistochemistry. Results: STCM-MXD-NPs improved MXD solubility. They released the drug slowly, increasing its transdermal properties, accumulation in the skin, and content in the hair bulb tissues with a better efficacy than that of ordinary MXD. Moreover, STCM-MXD-NPs significantly upregulated the mRNA and protein levels of VEGF and IGF-1 and promoted the protein expression of MKI67 and CTNNB in mouse skin tissues, promoting mouse hair growth. Conclusion: Stem cell membrane-loaded MXD nanoparticles with slow-release properties increased MXD accumulation in the skin by improving its transdermal properties, increasing VEGF, IGF-1, MKI67, and CTNNB expression levels and promoting hair growth in C57BL/6J mice.

Recent advances in hydrogels-based osteosarcoma therapy.

Osteosarcoma (OS), as a typical kind of bone tumors, has a high incidence among adolescents. Traditional tumor eradication avenues for OS such as chemotherapy, surgical therapy and radiation therapy usually have their own drawbacks including recurrence and metastasis. In addition, another serious issue in the treatment of OS is bone repair because the bone after tumor invasion usually has difficulty in repairing itself. Hydrogels, as a synthetic or natural platform with a porous three-dimensional structure, can be applied as desirable platforms for OS treatment. They can not only be used as carriers for tumor therapeutic drugs but mimic the extracellular matrix for the growth and differentiation of mesenchymal stem cells (MSCs), thus providing tumor treatment and enhancing bone regeneration at the same time. This review focuses the application of hydrogels in OS suppression and bone regeneration, and give some suggests on future development.

Spray-Coated Superhydrophobic Overlayer with Photothermal and Electrothermal Functionalities for All-Weather De/anti-icing Applications.

High-performance de/anti-icing overlayers which can be deposited on diverse surfaces offer great potential in many industrial settings and daily life, yet a versatile overlayer applicable to all-weather conditions (high humidity, low temperature, raining, snowing, etc.) is in high demand for practical applications. This study presents the fabrication and application of a superhydrophobic overlayer with a bioinspired hierarchical surface which additionally possesses photothermal and electrothermal functionalities, so it can operate as a de/anti-icing layer in extreme environments. The overlayer, with a papilla-like microstructure similar to that of a lotus leaf, features polydopamine-decorated layered basic zinc acetate microparticles distributed in the framework of multiwalled carbon nanotubes. Specifically, the overlayer is superhydrophobic, and its capability of suppressing the condensation of water droplets and growth of ice crystals is verified by both in situ environmental scanning electron microscopy observations and freezing experiments. Moreover, the overlayer can be warmed up to 74 and 105 °C under the excitation of sunlight and direct current bias, respectively, which is sufficiently high for deicing in severe weather. It is worth mentioning that the overlayer is produced by a spray-coating technique; therefore, it is suitable for large-scale deployment on arbitrary substrate materials. The findings provide insights into a new strategy for engineering multifunctional overlayers and can lead to expanding applications of composite coatings.

Full-Fiber Auxetic-Interlaced Yarn Sensor for Sign-Language Translation Glove Assisted by Artificial Neural Network.

Yarn sensors have shown promising application prospects in wearable electronics owing to their shape adaptability, good flexibility, and weavability. However, it is still a critical challenge to develop simultaneously structure stable, fast response, body conformal, mechanical robust yarn sensor using full microfibers in an industrial-scalable manner. Herein, a full-fiber auxetic-interlaced yarn sensor (AIYS) with negative Poisson's ratio is designed and fabricated using a continuous, mass-producible, structure-programmable, and low-cost spinning technology. Based on the unique microfiber interlaced architecture, AIYS simultaneously achieves a Poisson's ratio of-1.5, a robust mechanical property (0.6 cN/dtex), and a fast train-resistance responsiveness (0.025 s), which enhances conformality with the human body and quickly transduce human joint bending and/or stretching into electrical signals. Moreover, AIYS shows good flexibility, washability, weavability, and high repeatability. Furtherly, with the AIYS array, an ultrafast full-letter sign-language translation glove is developed using artificial neural network. The sign-language translation glove achieves an accuracy of 99.8% for all letters of the English alphabet within a short time of 0.25 s. Furthermore, owing to excellent full letter-recognition ability, real-time translation of daily dialogues and complex sentences is also demonstrated. The smart glove exhibits a remarkable potential in eliminating the communication barriers between signers and non-signers.

From Mesoscopic Functionalization of Silk Fibroin to Smart Fiber Devices for Textile Electronics and Photonics.

Bombyx mori silk fibers exhibit significant potential for applications in smart textiles, such as fiber sensors, fiber actuators, optical fibers, and energy harvester. Silk fibroin (SF) from B. mori silkworm fibers can be reconstructed/functionalized at the mesoscopic scale during refolding from the solution state into fibers. This facilitates the mesoscopic functionalization by engaging functional seeds in the refolding of unfolded SF molecules. In particular, SF solutions can be self-assembled into regenerated fiber devices by artificial spinning technologies, such as wet spinning, dry spinning, microfluidic spinning, electrospinning, and direct writing. Meso-functionalization manipulates the SF property from the mesoscopic scale, transforming the original silk fibers into smart fiber devices with smart functionalities, such as sensors, actuators, optical fibers, luminous fibers, and energy harvesters. In this review, the progress of mesoscopic structural construction from SF materials to fiber electronics/photonics is comprehensively summarized, along with the spinning technologies and fiber structure characterization methods. The applications, prospects, and challenges of smart silk fibers in textile devices for wearable personalized healthcare, self-propelled exoskeletons, optical and luminous fibers, and sustainable energy harvesters are also discussed.

New Silk Road: From Mesoscopic Reconstruction/Functionalization to Flexible Meso-Electronics/Photonics Based on Cocoon Silk Materials.

Two of the key questions to be addressed are whether and how one can turn cocoon silk into fascinating materials with different electronic and optical functions so as to fabricate the flexible devices. In this review, a comprehensive overview of the unique strategy of mesoscopic functionalization starting from silk fibroin (SF) materials to the fabrication of various meso flexible SF devices is presented. Notably, SF materials with novel and enhanced properties can be achieved by mesoscopically reconstructing the hierarchical structures of SF materials. This is based on rerouting the refolding process of SF molecules by meso-nucleation templating. As-acquired functionalized SF materials can be applied to fabricate bio-compatible/degradable flexible/implantable meso-optical/electronic devices of various types. Consequently, functionalized SF can be fabricated into optical elements, that is, nonlinear photonic and fluorescent components, and make it possible to construct silk meso-electronics with high-performance. These advances enable the applications of SF-material based devices in the areas of physical and biochemical sensing, meso-memristors, transistors, brain electrodes, and energy generation/storage, applicable to on-skin long-term monitoring of human physiological conditions, and in-body sensing, information processing, and storage.

Biomimetic Salinity Power Generation Based on Silk Fibroin Ion-Exchange Membranes.

Powering implanted medical devices (IMDs) is a long-term challenge since their use in biological environments requires a long-term and stable supply of power and a biocompatible and biodegradable battery system. Here, silk fibroin-based ion-exchange membranes are developed using bionics principles for reverse electrodialysis devices (REDs). Silk fibroin nanofibril (SNF) membranes are negatively and positively modified, resulting in strong cation and anion selectivity that regulates ion diffusion to generate electric power. These oppositely charged SNF membranes are assembled with Ag/AgCl electrodes into a multicompartment RED. By filling them with 10 and 0.001 mM NaCl solutions, a maximum output power density of 0.59 mW/m2 at an external loading resistance of 66 kΩ is obtained. In addition, 10 pairs of SNF membranes produce a considerable voltage of 1.58 V. This work is a proof of concept that key components of battery systems can be fabricated with protein materials. Combined with the emergence of water-based battery technologies, the findings in this study provide insights for the construction of tissue-integrated batteries for the next generation of IMDs.

Direct Single-Step Printing of Conductive Grids on Curved Surfaces Using Template-Guided Foaming.

Advanced transparent conductors have been studied intensively in the aspects of materials, structures, and printing methods. The material and structural advancements have been successfully accomplished with various conductive nanomaterials and spring-like structures for better electrical conductivity and high mechanical flexibility of the transparent conductors. However, the capability to print submicrometer conductive patterns directly and conformally on curved surfaces with low processing cost and high throughput remains a technological challenge to achieve, primarily because of the original two-dimensional (2D) nature of conventional lithography processes. In our study, we exploit a liquid-mediated patterning approach in the development of flexible templates, enabling printing of curvilinear silver grids in a single-step and strain-free manner at a submicrometer resolution within several minutes with minimum loss of noble metals. The template can guide arrays of receding liquid-air interfaces on curved substrates during liquid evaporation, thereby generating ordered 2D foam structures that can confine and assemble silver nanoparticles in grid patterns. The printed silver grids exhibit suitable optical, electrical, and Joule-heating performances, enabling their application in transparent heaters. Our technique has the potential to extend the existing 2D micro/nanofluidic liquid-mediated patterning approach to three-dimensional (3D) control of liquid-air interfaces for low-cost all-liquid-processed functional 3D optoelectronics in the future.

Review of microfluidic approaches for fabricating intelligent fiber devices: importance of shape characteristics.

Shape characteristics, which include the physical dimensions (scale), apparent morphology, surface features, and structure, are essential factors of fibrous materials and determine many of their properties. Microfluidic technologies have recently been proposed as an approach for producing one-dimensional (1D) fibers with controllable shape characteristics and particle alignment, which impart specific functionality to the fiber. Moreover, superfine 1D fibers with a high surface area and ordered structure have many potential applications as they can be directly braided or woven into textiles, clothes, and tissues with two- or three-dimensional (2D or 3D) structures. Previous reviews of microfluidic spinning have not focus on the importance of the shape characteristic on fiber performance and their use in intelligent fiber design. Here, the latest achievements in microfluidic approaches for fiber-device fabrication are reviewed considering the underlying preparation principles, shape characteristics, and functionalization of the fibers. Additionally, intelligent fiber devices with shapes tailored by microfluidic approaches are discussed, including 1D sensors and actuators, luminous fibers, and devices for encoding, energy harvesting, water collection, and tissue engineering applications. Finally, recent progress, challenges, and future perspectives of the microfluidic approaches for fiber device fabrication are discussed.

A capacitive humidity sensor based on all-protein embedded with gold nanoparticles @ carbon composite for human respiration detection.

Wool and silk fiber are the most extensive resources of protein fibers and have been used in the textile field for many years. The extracted biocompatible proteins are more and more widely used in flexible devices, sensors, tissue engineering, etc. Here, a fully biomaterial based flexible humidity sensor has been successfully fabricated for the first time. Interdigital electrodes of humidity sensor are printed on a transparent sensor substrate made of silk protein by inkjet printing. The humidity sensitive material is gold nanoparticles hosted nitrogen doped carbon (AuNPs@NC), which is fabricated by in situ dispersion of gold nanoparticles in a wool keratin assisted porous carbon precursor. The best treatment condition of the sensitive materials is obtained by comparing the sensitivity of humidity response. Moreover, the as-prepared biocompatible flexible sensor was successfully used to detect human respiration.