Liquid metal compartmented by polyphenol-mediated nanointerfaces enables high-performance thermal management on electronic devices

The exponentially increasing heat generation in electronic devices,induced by high power density and miniaturization,has become a dominant issue that affects carbon footprint,cost,performance,reliability,and lifespan.Liquid metals(LMs)with high thermal conductivity are promising candidates for effective thermal management yet are facing pump-out and surface-spreading issues.Confinement in the form of metallic particles can address these problems,but apparent alloying processes elevate the LM melting point,leading to severely deteriorated stability.Here,we propose a facile and sustainable approach to address these challenges by using a biogenic supramolecular network as an effective diffusion barrier at copper particle-LM(EGaIn/Cu@TA)interfaces to achieve superior thermal conduction.The supramolecular network promotes LM stability by reducing unfavorable alloying and fluidity transition.The EGaIn/Cu@TA exhibits a record-high metallic-mediated thermal conductivity(66.1 W m^(-1) K^(-1))and fluidic stability.Moreover,mechanistic studies suggest the enhanced heat flow path after the incorporation of copper particles,generating heat dissipation suitable for computer central processing units,exceeding that of commercial silicone.Our results highlight the prospects of renewable macromolecules isolated from biomass for the rational design of nanointerfaces based on metallic particles and LM,paving a new and sustainable avenue for high-performance thermal management.

Alloyed nanostructures integrated metal-phenolic nanoplatform for synergistic wound disinfection and revascularization

New materials for combating bacteria-caused infection and promoting the formation of microvascular networks during wound healing are of vital importance.Although antibiotics can be used to prevent infection,treatments that can disinfect and accelerate wound healing are scarce.Herein,we engineer a coating that is both highly compatible with current wound dressing substrates and capable of simultaneously disinfecting and revascularizing wounds using a metal-phenolic nanoplatform containing an alloyed nanostructured architecture(Ag@Cu-MPNNC).The alloyed nanostructure is formed by the spontaneous co-reduction and catalytic disproportionation reaction of multiple metal ions on a foundation metal-phenolic supramolecular layer.This synergistic presence of metals greatly improves the antibacterial activity against both Gram-negative and Gram-positive pathogenic bacteria,while demonstrating negligible cytotoxicity to normal tissue.In infected rat models,the Ag@Cu-MPNNC could kill bacteria efficiently,promoting revascularization and accelerate wound closure with no adverse side effects in infected in vivo models.In other words,this material acts as a combination therapy by inhibiting bacterial invasion and modulating bio-nano interactions in the wound.

Collagen-based materials in reproductive medicine and engineered reproductive tissues

Collagen,the main component of mammal skin,has been traditionally used in leather manufacturing for thousands of years due to its diverse physicochemical properties.Collagen is the most abundant protein in mammals and the main component of the extracellular matrix(ECM).The properties of collagen also make it an ideal building block for the engineering of materials for a range of biomedical applications.Reproductive medicine,especially human fertility preservation strategies and reproductive organ regeneration,has attracted significant attention in recent years as it is key in resolving the growing social concern over aging populations worldwide.Collagen-based biomaterials such as collagen hydrogels,decellularized ECM(dECM),and bioengineering techniques including collagen-based 3D bio-printing have facilitated the engineering of reproductive tissues.This review summarizes the recent progress in apply-ing collagen-based biomaterials in reproductive.Furthermore,we discuss the prospects of collagen-based materials for engineering artificial reproductive tissues,hormone replacement therapy,and reproductive organ reconstruction,aiming to inspire new thoughts and advancements in engineered reproductive tissues research.

A biologically stable, self-catalytic DNAzyme machine encapsulated by metal-phenolic nanoshells for multiple microRNA imaging

DNAzyme machines play critical roles in the fields of cell imaging, disease diagnosis, and cancer therapy. However, the applications of DNAzyme machines are limited by the nucleases-induced degradation,non-specific binding of proteins, and insufficient provision of cofactors. Herein, protected DNAzyme machines with different cofactor designs(referred to as Pro Ds) were nanoengineered by the construction of multifunctional metal-phenolic nanoshells to deactivate the interferential proteins, including nucleases and non-specific binding proteins. Moreover, the nanoshells not only facilitate the cellular internalization of Pro Ds but provide specific metal ions acting as cofactors of the designed DNAzymes. Cellular imaging results demonstrated that Pro Ds could effectively and simultaneously monitor multiple tumor-related micro RNAs in living cells. This facile and rapid strategy that encapsulates DNAzyme machines into the protective metal-phenolic nanoshells is anticipated to extend to a wide range of functional nucleic acidsbased biomedical applications.

Engineering microparticles based on solidified stem cell secretome with an augmented pro-angiogenic factor portfolio for therapeutic angiogenesis

Tissue (re)vascularization strategies face various challenges, as therapeutic cells do not survive long enough in situ, while the administration of pro-angiogenic factors is hampered by fast clearance and insufficient ability to emulate complex spatiotemporal signaling. Here, we propose to address these limitations by engineering a functional biomaterial capable of capturing and concentrating the pro-angiogenic activities of mesenchymal stem cells (MSCs). In particular, dextran sulfate, a high molecular weight sulfated glucose polymer, supplemented to MSC cul-tures, interacts with MSC-derived extracellular matrix (ECM) components and facilitates their co-assembly and accumulation in the pericellular space. Upon decellularization, the resulting dextran sulfate-ECM hybrid material can be processed into MIcroparticles of SOlidified Secretome (MIPSOS). The insoluble format of MIPSOS protects protein components from degradation, while facilitating their sustained release. Proteomic analysis demonstrates that MIPSOS are highly enriched in pro-angiogenic factors, resulting in an enhanced pro-angiogenic bioactivity when compared to naïve MSC-derived ECM (cECM). Consequently, intravital microscopy of full-thickness skin wounds treated with MIPSOS demonstrates accelerated revascularization and healing, far superior to the ther-apeutic potential of cECM. Hence, the microparticle-based solidified stem cell secretome provides a promising platform to address major limitations of current therapeutic angiogenesis approaches.

Near infrared light-induced dynamic modulation of enzymatic activity through polyphenol-functionalized liquid metal nanodroplets

Dynamic manipulation of enzymatic activity is a challenging task for applications in chemical and pharmaceutical industries due to the difficult modification and variable conformation of various enzymes.Here, we report a new strategy for reversible dynamic modulation of enzymatic activity by near-infrared light-induced photothermal conversion based on polyphenol-functionalized liquid metal nanodroplets(LM). The metal-phenolic nanocoating not only provides colloidal stability of LM nanodroplets but also generates nanointerfaces for the assembly of various enzymes on the LM nanodroplets. Upon near infrared(NIR) irradiation, the localized microenvironmental heating through photothermal effect of the LM nanodroplets allows tailoring the enzymatic activity without affecting the bulk temperature. A library of functional enzymes, including proteinase K, glucoamylase, glucose oxidase, and Bst DNA polymerase, is integrated to perform a reversible control and enhanced activities even after five times of cycles, demonstrating great potential in bacterial fermentation, bacteriostasis, and target gene amplification.

The role of extracellular matrix on unfavorable maternal-fetal interface:focusing on the function of collagen in human fertility

Extracellular matrix(ECM)is characterized as widespread,abundant,and pluripotent.Among ECM members,collagen is widely accepted as one of the most prominent components for its essential structural property that can provide a scaffold for other components of ECM and the rich biological functions,which has been extensively used in tissue engineering.Emerging evidence has shown that the balance of ECM degradation and remodeling is vital to regulations of maternal-fetal interface including menstrual cycling,decidualization,embryo implantation and pregnancy maintenance.Moreover,disorders in these events may eventually lead to failure of pregnancy.Although the improvement of assisted conception and embryo culture technologies bring hope to many infertile couples,some unfavorable outcomes,such as recurrent implantation failure(RIF),recurrent pregnancy loss(RPL)or recurrent miscarriage(RM),keep troubling the clinicians and patients.Recently,in vitro three-dimensional(3D)model mimicking the microenvironment of the maternal-fetal interface is developed to investigate the physiological and pathological conditions of conception and pregnancy.The progress of this technology is based on clarifying the role of ECM in the endometrium and the interaction between endometrium and conceptus.Focusing on collagen,the present review summarized the degradation and regulation of ECM and its role in normal menstruation,endometrium receptivity and unsatisfying events occurring in infertility treatments,as well as the application in therapeutic approaches to improve pregnancy outcomes.More investigations about ECM focusing on the maternal-fetal interface interaction with mesenchymal stem cells or local immunoregulation may inspire new thoughts and advancements in the clinical application of infertility treatments.