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Nano‐delivery systems hold great promise for the treatment of rheumatoid arthritis (RA). Current research efforts are primarily focused on enhancing their targeting capabilities and efficacy. Here, this study proposes a novel viral‐mimicking ternary polyplexes system for the controlled delivery of the anti‐inflammatory drug Cyclosporin A (CsA) to effectively treat RA. The ternary polyplexes consist of a nanogel core loaded with CsA and a hyaluronic acid shell, which facilitates CD44‐mediated targeting. By mimicking the Trojan Horse strategy employed by viruses, these polyplexes undergo a stepwise process of deshielding and disintegration within the inflamed joints. This process leads to the release of CsA within the cells and the scavenging of pathogenic factors. This study demonstrates that these viral‐mimicking ternary polyplexes exhibit rapid targeting, high accumulation, and prolonged persistence in the joints of RA mice. As a result, they effectively reduce inflammation and alleviate symptoms. These results highlight the potential of viral‐mimicking ternary polyplexes as a promising therapeutic approach for the targeted and programmed delivery of drugs to treat not only RA but also other autoimmune diseases. [ABSTRACT FROM AUTHOR]

Advanced artificial nerve conduits offer a promising alternative for nerve injury repair. Current research focuses on improving the therapeutic effectiveness of nerve conduits by optimizing scaffold materials and functional components. In this study, a novel poly(3,4‐ethylenedioxythiophene) (PEDOT)‐integrated fish swim bladder (FSB) is presented as a conductive nerve conduit with ordered topology and electrical stimulation to promote nerve regeneration. PEDOT nanomaterials and adhesive peptides (IKVAV) are successfully incorporated onto the decellularized FSB substrate through pre‐coating with polydopamine. The obtained PEDOT/IKVAV‐integrated FSB substrate exhibits outstanding mechanical properties, high electrical conductivity, stability, as well as excellent biocompatibility and bioadhesive properties. In vitro studies confirm that the PEDOT/IKVAV‐integrated FSB can effectively facilitate the growth and directional extension of pheochromocytoma 12 cells and dorsal root ganglion neurites. In addition, in vivo experiments demonstrate that the proposed PEDOT/IKVAV‐integrated FSB conduit can accelerate defective nerve repair and functional restoration. The findings indicate that the FSB‐derived conductive nerve conduits with multiple regenerative inducing signals integration provide a conducive milieu for nerve regeneration, exhibiting great potential for repairing long‐segment neural defects. [ABSTRACT FROM AUTHOR]

Microfibers from natural products are endowed with remarkable biocompatibility, biodegradability, sustainable utilization as well as environmental protection characteristics etc. Benefitting from these advantages, microfibers have demonstrated their prominent values in biomedical applications. This review comprehensively summarizes the relevant research progress of sustainable microfibers from natural products and their biomedical applications. To begin, common natural elements are introduced for the microfiber fabrication. After that, the focus is on the specific fabrication technology and process. Subsequently, biomedical applications of sustainable microfibers are discussed in detail. Last but not least, the main challenges during the development process are summarized, followed by a vision for future development opportunities. [ABSTRACT FROM AUTHOR]

Osteoarthritis has been regarded as a complex and serious degenerative disease. Attempts in this area are focused on improving the curative effect of stem cell‐based therapies. In this work, we present a novel inverse opal microcarriers‐based cytokines delivery system to induce autologous stem cell homing for osteoarthritis treatment. Considering their important role in stem cell recruitment and chondrogenic differentiation respectively, platelet‐derived growth factor BB (PDGF‐BB) and transforming growth factor β3 (TGF‐β3) are loaded into inverse opal microcarriers as model cytokines. Since cytokine release induces the corresponding variations in characteristic reflection spectra and structural colors, the inverse opal microcarriers possess the optical self‐reporting capacity to monitor the release process. In vitro cell experiments reveal that inverse opal microcarriers could successfully recruit the gathering of mesenchymal stem cells through the release of loaded cytokines. Based on these features, we have demonstrated the enhanced therapeutic effect of PDGF‐BB and TGF‐β3 loaded inverse opal microcarriers in the treatment of rat osteoarthritis models. These results indicate that the multifunctional inverse opal microcarriers‐based cytokines delivery system would find broad prospects in osteoarthritis treatment and other biomedical fields. [ABSTRACT FROM AUTHOR]

Reactive oxygen species (ROS) have certain effect in cancer treatment, thus many studies have been focused on developing functional systems to generate ROS in tumor. Here, inspired by the multi‐enzyme biocatalysis in organisms, novel ultrasound‐triggered temporospatial catalytic cascades systems are presented based on barium titanate (BTO) and platinum (Pt) co‐loaded multi‐component microparticles (Pt/BTO@MCMPs) to successively achieve oxygen and ROS production for tumor sonodynamic therapy. By using a customized capillary microfluidic device, the Pt/BTO@MCMPs are fabricated with Pt nanoparticles located in their core part and BTO nanocubes located in their peripheral part, alternating with blank porous hydrogel components for increasing interaction areas between the encapsulated nanomaterials and the ambient substrates. In the microparticles, the Pt can catalyze hydrogen peroxide from the tumor microenvironment to generate O2 and H2O serving as substrates for piezoelectric catalytic reactions, contributing to additional generation of ROS under US activation. Based on the system, it is demonstrated that the Pt/BTO@MCMPs are featured with excellent biocompatibility under normal biological conditions and show desired tumor eradication properties under ultrasound irradiation in mice carrying pancreatic tumors. These results indicate that the proposed ultrasound‐triggered temporospatial catalytic cascades systems are promising for clinic anti‐tumor applications. [ABSTRACT FROM AUTHOR]

Diabetic wound healing is a serious, complex, and chronic process; one current promising and focusing technology in this area is stem cell treatment. Here, novel porous microneedle (MN) arrays is fabricated, which can highly mimetic stem cell niches, through template filling, and particle etching method. The human adipose‐derived stem cells (ADSCs) are encapsulated in Matrigel then loaded into the porous MN arrays by post‐perfusion. Because of the extracellular matrix‐mimicking, the biocompatible Matrigel offers a bionic microenvironment of stem cell nest suitable for growth. Benefiting from the numerous pore structures of MNs, the loaded ADSCs have enough space to fully absorb nutrients, proliferate greatly and exhibit prompted function. In addition, the cell‐loaded MN arrays have enough mechanical strength to penetrate the skin, allowing the ADSCs to get into the deep wound areas. Based on these features, the performance of the resultant MN arrays in promoting tissue regeneration is demonstrated, collagen deposition and angiogenesis in diabetes wounds of rat models. Thus, it is believe that the bioinspired porous MNs can act as excellent stem cell scaffolds and will find many practical values in clinic wound healing. [ABSTRACT FROM AUTHOR]

Localized chemotherapy is emerging as a potential strategy for cancer treatment due to its low systemic toxicity. However, the immune evasion of tumor cells and the lack of an intelligent design of the delivery system limit its clinical application. Herein, photothermal responsive microcarriers are designed by microfluidic electrospray for colorectal tumor treatment. The microcarriers loaded with Cangrelor, 5‐FU and MXene (G‐M@F/C+NIR) show sustained delivery of antiplatelet drug Cangrelor, thus inhibiting the activity of platelets, interactions of platelet‐tumor cell, as well as the tumor cells invasion and epithelial‐mesenchymal transition (EMT). In addition, the sustained delivery of chemotherapeutics 5‐FU and the photothermal effect provided by MXene enable the microcarriers to inhibit tumor cells proliferation and migration. In vivo studies validate that the G‐M@F/C+NIR microcarriers significantly inhibites tumor growth, decreased the expression of Ki‐67 in tumor cells and vascular endothelial growth factor (VEGF) in the tumor microenvironment, while increased the expression of E‐cadherin. It is believe that by means of the proposed photothermal responsive microcarriers, the synergistic strategy of platelet inhibition, chemotherapy, and photothermal therapy can find practical applications in cancer treatment. [ABSTRACT FROM AUTHOR]

Bacterial skin infections are highly prevalent and pose a significant public health threat. Current strategies are primarily focused on the inhibition of bacterial activation while disregarding the excessive inflammation induced by dead bacteria remaining in the body and the effect of the acidic microenvironment during therapy. In this study, a novel dual‐functional MgB2 microparticles integrated microneedle (MgB2 MN) patch is presented to kill bacteria and eliminate dead bacteria for skin infection management. The MgB2 microparticles not only can produce a local alkaline microenvironment to promote the proliferation and migration of fibroblasts and keratinocytes, but also achieve >5 log bacterial inactivation. Besides, the MgB2 microparticles effectively mitigate dead bacteria‐induced inflammation through interaction with lipopolysaccharide (LPS). With the incorporation of these MgB2 microparticles, the resultant MgB2 MN patches effectively kill bacteria and capture dead bacteria, thereby mitigating these bacteria‐induced inflammation. Therefore, the MgB2 MN patches show good therapeutic efficacy in managing animal bacterial skin infections, including abscesses and wounds. These results indicate that reactive metal borides‐integrated microneedle patches hold great promise for the treatment of clinical skin infections. [ABSTRACT FROM AUTHOR]

Anticoagulation is vital to maintain blood fluidic status and physiological functions in the field of clinical blood‐related procedures. Here, novel biomimetic anticoagulated porous inverse opal hydrogel particles is presented as anticoagulant bearing dynamic screening capability. The inverse opal hydrogel particles possess abundant sulfonic and carboxyl groups, which serve as binding sites with multiple coagulation factors and inhibit the blood coagulation process. Owing to the variations of refractive index and pore sizes during the binding process, the particles appeared corresponding structure color variations, which can be adopted as sensory index of anticoagulation. Based on these features, a sensor containing these diverse structure color particle units is constructed for pattern recognition of coagulation factors level in clinical plasma samples. By analyzing the sensory information of the unit, the colorimetric "fingerprint" for each target can be obtained and summarized as a database. Besides, a portable test‐strip integrating sensory units is developed to distinguish the sample regarding abnormal coagulation factors‐derived diseases via multivariate data analysis. It is believed that such biomimetic anticoagulated structural color particles and their derived sensor will open new avenue for clinical detection and disease diagnosis. [ABSTRACT FROM AUTHOR]

The management of infected wounds is always of great significance and urgency in clinical and biomedical fields. Recent efforts in this area are focusing on the development of functional wound patches with effective antibacterial, drug delivery, and sensor properties. Here, we present novel hyaluronic acid (HA) microneedle patches with these features by encapsulating aminobenzeneboronic acid‐modified gold nanoclusters (A‐GNCs) for infected wound management. The A‐GNCs loaded microneedle patches were derived from negative‐mold replication and showed high mechanical strength to penetrate the skin. The release of the A‐GNCs was realized by the degradation of HA, and the self‐monitor of the released actives was based on the dynamic bright orange fluorescence emitted from A‐GNCs under ultraviolet radiation. As the A‐GNCs could destroy bacteria membranes, the microneedle patches were with excellent in vitro antibiosis ability. Based on these features, we have demonstrated the bacteria inhibition, residual drug self‐monitoring, and wound healing promotion abilities of the microneedle patches in Escherichia coli‐ or Staphylococcus aureus‐infected wound management. These results indicated the great potential of such A‐GNCs loaded microneedle patches for clinical applications. [ABSTRACT FROM AUTHOR]

The intricate physiological structure of the inner ear presents challenges for traditional medication treatment strategies, including systemic adverse responses, trouble penetrating the blood–labyrinth barrier, and low local cochlear concentration, resulting in poor therapeutic outcomes. An intriguing tactic that is extensively developed over decades is utilizing drug delivery systems to transport medication molecules to the inner ear. Herein, the challenges associated with inner ear delivery are discussed, cutting‐edge achievements in inner ear drug delivery systems are emphasized, including nano‐, micro‐, and macrocarriers, and finally opportunities to leverage advanced technologies to improve existing drug delivery strategies are highlighted. [ABSTRACT FROM AUTHOR]

Biomedical patches offer significant potential for keratitis treatment. Building on advances in multifunctionality and biomimicry, an innovative, multifunctional hydrogel patch with high therapeutic efficacy, inspired by the native architecture and functions of the cornea, is introduced. By engineering a composite patch comprising recombinant human collagen (RHC) hydrogel, near‐field electrospinning (NFES) microfibers, and gold‐nanoparticle‐decorated tetragonal barium titanates (BTO@Au), structural mimicry, mechanical reinforcement, tissue‐specific adhesion, and bacterial inhibition are achieved. The RHC hydrogel recreates a three‐dimensional (3D) microenvironment that emulates the natural structure of the corneal tissue, demonstrating excellent tissue adhesion. Integrated within this hydrogel, the NFES microfibers, designed to emulate the orthogonal arrangement of native corneal stroma, not only reinforce the mechanical strength of the RHC hydrogel but also act as scaffolds to guide the aligned growth of human keratocytes. A unique aspect of this advanced patch is the incorporation of BTO@Au nanoparticles, which generate reactive oxygen species for effective bacterial eradication when subjected to ultrasound stimulation. Through in vivo studies on rat models with infected corneal wounds, this hydrogel patch exhibits superior therapeutic efficacy compared to the current treatment. It is posited that these cornea‐inspired ultrasound‐responsive adhesive hydrogel patches represent a significant scientific advancement with high potential for clinical applications. [ABSTRACT FROM AUTHOR]

Human organoid models potentially offer a physiologically relevant platform to replace traditional monolayer cultures and animal models. In particular, the rapid development of engineered strategies including microfluidics, hydrogel, 3D printing and others, which have enormous advantages in comparison to conventional methods, is expected to further advance organoid technology. Up to now, many studies have demonstrated the engineered organoid models with complex cell composition, controlled structure, enhanced maturation, reduced heterogeneity, and so on. These engineered organoids are high promising for studies in development, disease, tissue repair, precision medicine and drug screening. In this review, a comprehensive summary of the engineered organoid model systems is provided based on microfluidics, hydrogel, 3D printing and so on. Then, the biomedical applications of these models are highlighted, which have displayed the great power in organoid field. Finally, the key bottlenecks and future development of organoid models are discussed about from an engineering perspective. [ABSTRACT FROM AUTHOR]

Noise‐induced hearing loss (NIHL) is a common outcome of excessive reactive oxygen species in the cochlea, and the targeted delivery of antioxidants to the inner ear is a potential therapeutic strategy. In this paper, a novel natural biomaterials‐derived multifunctional delivery system using silk fibroin‐polydopamine (PDA)‐composited inverse opal microcarriers (PDA@SFMCs) is presented for inner ear drug delivery and NIHL therapy. Due to their large specific surface area and interpenetrating nanochannels, PDA@SFMCs can rapidly load active biomolecules making them a convenient medium for the storage and delivery of such molecules. In addition, surface modification of PDA enables the microcarriers to remain in the round window niche, thus facilitating the precise local and directed delivery of loaded drugs. Based on these features, it is demonstrated here that n‐acetylcysteine‐loaded silk microcarriers have satisfactory antioxidant properties on cells and can successfully prevent NIHL in guinea pigs. These results indicate that the natural multifunctional silk microcarriers are promising agents for local inner ear drug delivery in the clinic. [ABSTRACT FROM AUTHOR]

Tumor tissue engineering holds great promise for replicating the physiological and behavioral characteristics of tumors in vitro. Advances in this field have led to new opportunities for studying the tumor microenvironment and exploring potential anti‐cancer therapeutics. However, the main obstacle to the widespread adoption of tumor models is the poor understanding and insufficient reconstruction of tumor heterogeneity. In this review, the current progress of engineering heterogeneous tumor models is discussed. First, the major components of tumor heterogeneity are summarized, which encompasses various signaling pathways, cell proliferations, and spatial configurations. Then, contemporary approaches are elucidated in tumor engineering that are guided by fundamental principles of tumor biology, and the potential of a bottom‐up approach in tumor engineering is highlighted. Additionally, the characterization approaches and biomedical applications of tumor models are discussed, emphasizing the significant role of engineered tumor models in scientific research and clinical trials. Lastly, the challenges of heterogeneous tumor models in promoting oncology research and tumor therapy are described and key directions for future research are provided. [ABSTRACT FROM AUTHOR]

Rheumatoid arthritis (RA) is one of the leading causes of disability due to the autoimmune destruction of synovial joints. Great efforts have been put into developing multifunctional drug delivery systems for delaying the progression of RA. Herein, a novel locally injectable, hierarchically structured delivery system with a hyaluronic acid (HA) microparticle and an MTX‐conjugated nanoparticle for promoted RA treatment is proposed. In this system, MTX is chemically grafted onto a peptide dendrimer‐based nanoparticle (G‐MTX). These nanoparticles are encapsulated inside HA microparticles (H‐G‐MTX) using microfluidics to realize the system. The G‐MTX can be released from the degradable HA microparticles in the acidic environment of inflamed RA joints. As the G‐MTX shows an enhanced intracellular delivery of the conjugated MTX, the H‐G‐MTX can reverse the dominant macrophage phenotype from M1 to M2. Through a collagen‐induced arthritis (CIA) rat model, the great therapeutic outcomes of this hierarchically structured delivery system are demonstrated, including inflammation reduction, cartilage protection, and bone mineral density promotion. These results indicate that the proposed hierarchical delivery system has potential clinical value in the treatment of RA and other diseases. [ABSTRACT FROM AUTHOR]

The development of bioactive scaffolds by mimicking bone tissue extracellular matrix is promising for bone regeneration. Herein, inspired by the bone tissue composition, a novel pearl powder (PP) hybrid fish gelatin methacrylate (GelMa) hydrogel scaffold loaded with vascular endothelial growth factor (VEGF) for bone regeneration is presented. With the help of microfluidic‐assisted 3D printing technology, the composition and structure of the hybrid scaffold can be accurately controlled to meet clinical requirements. The combination of fish skin GelMa and PP also endowed the hybrid scaffold with good biocompatibility, cell adhesion, and osteogenic differentiation ability. Moreover, the controlled release of VEGF enables the scaffold to promote angiogenesis. Thus, the bone regeneration in the proposed scaffolds could be accelerated under the synergic effect of osteogenesis and angiogenesis, which has been proved in the rat skull defect model. These features indicate that the PP hybrid scaffolds will be an ideal candidate for bone regeneration in clinical applications. [ABSTRACT FROM AUTHOR]

Hyaluronic acid (HA) is an attractive anionic polysaccharide polymer with inherent pharmacological properties and versatile chemical groups for modification. Due to their water retention ability, biocompatibility, biodegradation, cluster of differentiation‐44 targeting, and highly designable capacity, HA hydrogels have been an emerging biomaterial, showing tailoring performance in terms of chemical modifications and hydrogel forms. Various preparation technologies have been developed for the fabrication of the tailoring HA hydrogels with unique structures and functions. They have been utilized in diverse biomedical applications like drug delivery and tissue engineering scaffolds. Herein, this review comprehensively summarizes the HA derivatives with different molecule weights and functional modifications. Then the various fabrication methods to obtain tailoring hydrogels in the forms of nanogel, nanofiber, microparticle, microneedle patch, injectable hydrogel, and scaffold are reviewed as well. The emphasis is focused on the shining biomedical applications of these tailoring HA hydrogels in anti‐bacteria, anti‐inflammation, wound healing, cancer treatment, regenerative medicine, psoriasis treatment, diagnosis, etc. The potentials and prospects are subsequently given to inspire further investigation, aiming at accelerating product translation from research to clinic. [ABSTRACT FROM AUTHOR]

Metal–organic framework (MOF)‐based drug delivery systems have demonstrated values in oncotherapy. Current research endeavors are centralized on the functionality enrichment of featured MOF materials with designed versatility for synergistic multimodal treatments. Here, inspired by the multifarious biological functions including ferroptosis pattern, porphyrins, and cancer cell membrane (CCM) camouflage technique, novel multi‐biomimetic MOF nanocarriers from microfluidics are prepared. The Fe3+, meso‐tetra(4‐carboxyphenyl)porphine and oxaliplatin prodrug are incorporated into one MOF nano‐system (named FeTPt), which is further cloaked by CCM to obtain a "Trojan Horse"‐like vehicle (FeTPt@CCM). Owing to the functionalization with CCM, FeTPt@CCM can target and accumulate at the tumor site via homologous binding. After being internalized by cancer cells, FeTPt@CCM can be activated by a Fenton‐like reaction as well as a redox reaction between Fe3+ and glutathione and hydrogen peroxide to generate hydroxyl radical and oxygen. Thus, the nano‐platform effectively initiates ferroptosis and improves photodynamic therapy performance. Along with the Pt‐drug chemotherapy, the nano‐platform exhibits synergistic multimodal actions for inhibiting cancer cell proliferation in vitro and suppressing tumor growth in vivo. These features indicate that such a versatile biomimetic MOF delivery system from microfluidics has great potential for synergistic cancer treatment. [ABSTRACT FROM AUTHOR]

Mesenchymal stem cell (MSC) therapy is a promising candidate for inflammatory bowel disease (IBD) treatment, while overcoming the limitations of naive seeding cells function and realizing efficient intestinal targeting remains a challenge. Here, a bioadhesive microparticle carrying interleukin‐27 (IL‐27) MSC‐derived extracellular vesicles (MSCIL‐27 EVs) is developed to treat IBD. The MSCIL‐27 EVs prepared through lentivirus‐mediated gene transfection technology show ideal anti‐inflammatory and damage repair function. By encapsulating MSCIL‐27 EVs into dopamine methacrylamide‐modified hydrogel, a bioadhesive EVs microcarrier via microfluidic technology is fabricated. The resultant microcarriers exhibit ideal MSCIL‐27 EVs sustained release effect and effective wet adhesion property. Furthermore, the therapeutic potential of MSCIL‐27 EVs‐loaded microcarriers in treating IBD is demonstrated. Through giving IBD rats a rectal administration, it is found that the microcarriers can firmly anchor to the surface of colon, reduce the inflammatory response, and repair the damaged barrier. Therefore, the bioadhesive MSCIL‐27 EVs‐loaded microcarriers provide a promising strategy for the biomedical application of MSC‐derived EVs, and broaden the clinical potential of MSC therapy. [ABSTRACT FROM AUTHOR]

In diabetic wound healing, M1 macrophage accumulation and elevated inflammation are prevalent issues. Intelligent delivery systems that can sustainably release antioxidizing and anti‐inflammatory ingredients are expected for effective wound healing. Herein, a novel glycyrrhetinic acid (GA) liposomes encapsulated microcapsules delivery system that has desired features for inflammatory wound repair is presented. As the bacteria could break down the alginate shells, the GA liposomes could be controllably released from the microcapsules, which promotes M2 macrophage polarization and regulate their responses in the inflammatory wound microenvironment. Based on these, it is demonstrated that the GA liposomes encapsulated microcapsules delivery system exhibits an anti‐inflammatory and immunomodulatory effect for diabetic wound healing in a full‐thickness defect model in diabetic rats. These results indicate that the immunomodulatory capabilities of the microcapsules can be unitized for efficient wound repair, and such a delivery system is valuable for clinical wound healing applications. [ABSTRACT FROM AUTHOR]

Many hydrogel patches are developed to solve the pervasive and severe challenge of complex wound healing, while most of them still lack satisfactory controllability and comprehensive functionality. Herein, inspired by multiple creatures, including octopuses and snails, a novel muti‐functional hydrogel patch is presented with controlled adhesion, antibacterial, drug release features, and multiple monitoring functions for intelligent wound healing management. The patch with micro suction‐cup actuator array and a tensile backing layer is composed of tannin grafted gelatin, Ag‐tannin nanoparticles, polyacrylamide (PAAm) and poly(N‐isopropylacrylamide) (PNIPAm). In virtue of the photothermal gel‐sol transition of tannin grafted gelatin and Ag‐tannin nanoparticles, the patches exert a dual anti‐microbial effect and temperature‐sensitive snail mucus‐like features. In addition, as the "suction‐cups" consisting of thermal responsive PNIPAm can undergo a contract‐relax transformation, the medical patches can adhere to the objects reversibly and responsively, and release their loaded vascular endothelial growth factor (VEGF) controllably for wound healing. More attractively, benefiting from their fatigue resistance, self‐healing ability of the tensile double network hydrogel, and electrical conductivity of Ag‐tannin nanoparticles, the proposed patches can report multiple wound physiology parameters sensitively and continuously. Thus, it is believed that this multi‐bioinspired patch has immense potential for future wound healing management. [ABSTRACT FROM AUTHOR]

Peripheral nerve injuries are challenging to repair clinically due to their limited regenerative capacity. Herein, a novel poly(3,4‐ethylenedioxythiophene):poly(4‐styrene sulfonate) (PEDOT:PSS) composited conductive silk conduit with ultrasound (US)‐triggered active release for peripheral nerve regeneration is presented. The conduit is composed of silk fibroin inverse opal tubular scaffolds and the secondary hydrogel filler that contains thermosensitive material (poly(N‐isopropylacrylamide), PNIPAM), PEDOT:PSS, and nerve growth factor (NGF). Benefiting from the integration of these functional materials and active factors, the silk fibroin conduits show excellent biocompatibility, flexibility, conductivity, and bioactivity. In particular, owing to the thermal effect of US and the temperature responsiveness of PNIPAM, the secondary filling hydrogel undergoes volume shrinkage upon US triggering, allowing the responsive NGF release. Besides, the electrical conductivity of PEDOT:PSS has been affirmed to promote neuron and axon outgrowth. Through in vivo experiments, the synergistic effect of PEDOT:PSS and US‐triggered delivery of NGF on accelerating injured nerve repair are demonstrated. These results reveal the practical value of the proposed intelligent conductive silk conduits with US responsiveness for nerve regeneration in preclinical studies. [ABSTRACT FROM AUTHOR]

Hydrogel microrobots have blazed new avenues for local drug administration, while their values in inner ear drug delivery remain to be explored. Here, novel magnetic alpha‐lipoic acid (ALA)‐conjugated gelatin methacryloyl hydrogel microrobots are presented for inner ear drug delivery and deafness prevention. The magnetic hydrogel microrobots with features of slow drug release, targeted movement, and biosafety are generated from microfluidic devices. After intratympanic injection, the microrobots can be oriented in the middle ear cavity under a specific magnetic field. In addition, the ALA drug released from the magnetic hydrogel microrobots can remain in the inner ear for a long time. Based on these advantages, the practical value of the magnetic hydrogel microrobots in deafness prevention is demonstrated by pre‐injecting them in the middle ear of cisplatin‐deafened mice. These results indicate that the proposed smart magnetic hydrogel microrobots can effectively deliver drugs to the inner ear through the middle ear drug delivery route, thus opening a new chapter for middle ear deafness treatment. [ABSTRACT FROM AUTHOR]

Hydrogel patches have outstanding values in wound treatment; challenges in this field are concentrated on developing functional and intelligent hydrogel patches with new antibacterial strategies for improving healing process. Herein, a novel melanin‐integrated structural color hybrid hydrogel patches for wound healing is presented. Such hybrid hydrogel patches are fabricated by infusing asiatic acid (AA)‐loaded low melting‐point agarose (AG) pregel into the melanin nanoparticles (MNPs)‐integrated fish gelatin inverse opal film. In this system, MNPs not only impart the hybrid hydrogels with properties of photothermal antibacterial and antioxidant, but also improve the visibility of structural colors by providing an inherent dark background. Besides, the photothermal effect of MNPs under near‐infrared irradiation can also trigger liquid transformation of AG component in hybrid patch, resulting in the controllable release of its loaded proangiogenic AA. Attracting, this drug release induced refractive index variations in the patch can be detected as visible structural color shifting, which can be used to monitor their delivery processes. Benefiting from these features, the hybrid hydrogel patches are demonstrated to achieve excellent therapeutic effects for in vivo wound treatment. Thus, it is believed that the proposed melanin‐integrated structural color hybrid hydrogels are valuable as multifunctional patches for clinical applications. [ABSTRACT FROM AUTHOR]

The tumor‐suppressing efficacy of either chemotherapeutics or gaseous drugs has been confirmed in treating the triple negative breast cancer (TNBC), while the efficacy of single treatment is usually dissatisfactory. Herein, a novel ultrasound responsive natural pollen delivery system is presented to simultaneously load chemotherapeutics and gaseous drugs for synergistic treatment of TNBC. The hollow structure of pollen grains carries oxygen‐enriched perfluorocarbon (PFC), and the porous spinous process structure adsorbs the chemotherapeutic drug doxorubicin (DOX) (PO/D‐PGs). Ultrasound can trigger the oxygen release from PFC and excite DOX, which is not only a chemotherapeutic but also a sonosensitizer, to realize chemo‐sonodynamic therapy. The PO/D‐PGs are demonstrated to effectively enhance oxygen concentration and increase the production of reactive oxygen species in the presence of low‐intensity ultrasound, synergistically enhancing the tumor killing ability. Thus, the synergistic therapy based on ultrasound‐facilitated PO/D‐PGs significantly enhances the antitumor effect in the mouse TNBC model. It is believed that the proposed natural pollen cross‐state microcarrier can be used as an effective strategy to enhance chemo‐sonodynamic therapy for TNBC. [ABSTRACT FROM AUTHOR]

Fibrous scaffolds have shown their advantages in tissue engineering, such as peripheral nerve regeneration, while most of the existing fiber‐shaped scaffolds are with simple structures, and the in vitro performance for nerve regeneration lacks systematic analysis. Here, novel nerve‐on‐a‐chip derived biomimicking microfibers for peripheral nerve regeneration are presented. The microfibers with controllable core–shell structures and functionalities are generated through capillary microfluidic devices. By integrating these microfibers into a multitrack‐architectured chip, and coculturing them with nerve cells as well as gradient bioactive elements, the nerve‐on‐a‐chip with the capabilities of systematically assessing the performances of nerve fiber formation in the hollow microfibers at in vitro level is constructed. Based on a rat sciatic nerve injury model, the rapid promotion ability is demonstrated of optimized microfibers in nerve regeneration and function recovery in vivo, which implies the credibility of the nerve‐on‐a‐chip on biomimicking microfibers evaluation for peripheral nerve regeneration. Thus, it is convinced that the organ‐on‐a‐chip will undoubtedly open up a new chapter in evaluating biological scaffolds for in vivo tissue engineering. [ABSTRACT FROM AUTHOR]

Hard‐healing diabetic wound brings burgeoning physical and mental burdens to patients. Current treatment strategies tend to achieve multistage promotion and real‐time reporting to facilitate wound management. Herein, a biomimetic enzyme cascade inverse opal microparticles system for wound healing, which is intergated with glucose oxidase (GOD) and copper peroxide (CP). Such microparticles are composed of biofriendly hyaluronic acid methacryloyl (HAMA) and pH‐responsive acrylic acid (AA), which provided abundant binding sites and spaces for chemical immobilizing and physical doping of enzymes and metal bioinorganics. When the cascade catalytic system is applied on wound sites, hyperglycemia environment would serve as a hydrogen peroxide (H2O2) generator through GOD catalysis, while acidic environment triggers the decomposition of CP, further catalyzing H2O2 to generate reactive oxygen species (ROS). Additionally, the distinctive structural color of the microparticles can visually reflect the wound pH and intelligently estimate the healing state. It is demonstrated that such microparticle systems exhibit excellent broad‐spectrum antibacterial and angiogenesis‐promoting properties, as well as significant real‐time reporting ability for wound healing. These features indicate that enzyme cascade structural color microparticles possess valuable potential in wound healing and related field. [ABSTRACT FROM AUTHOR]