Complementary Homogeneous Electrochemical and Photothermal Dual-Modal Sensor for Highly Sensitive Detection of Organophosphorus Pesticides via Stimuli-Responsive COF/Methylene Blue@MnO2 Composite.

Credible and on-site detection of organophosphorus pesticides (OPs) in complex matrixes is significant for food security and environmental monitoring. Herein, a novel COF/methylene blue@MnO2 (COF/MB@MnO2) composite featured abundant signal loading, a specific recognition unit, and robust oxidase-like activity was successfully prepared through facile assembly processes. The multifunctional composite acted as a homogeneous electrochemical and photothermal dual-mode sensing platform for OPs detection through stimuli-responsive regulation. Without the presence of OPs, the surface MnO2 coating could recognize thiocholine (TCh), originating from acetylcholinesterase (AChE)-catalyzed hydrolysis of acetylthiocholine (ATCh), and exhibited a distinctly amplified diffusion current due to the release of plentiful MB; while the residual MnO2 nanosheets could only catalyze less TMB into oxidized TMB (oxTMB) with a typical near-infrared (NIR) absorption, enabling NIR-driven photothermal assay with a low temperature using a portable thermometer. Based on the inhibitory effect of OPs on AChE activity and OP-regulated generation of TCh, chlorpyrifos as a model target can be accurately detected with a low limit of detection of 0.0632 and 0.108 ng/mL by complementary electrochemical and photothermal measurements, respectively. The present dual-mode sensor was demonstrated to be excellent for application to the reliable detection of OPs in complex environmental and food samples. This work can not only provide a complementary dual-mode method for convenient and on-site detection of OPs in different scenarios but also expand the application scope of the COF-based multifunctional composite in multimodal sensors.

Multifunctional antibacterial bioactive nanoglass hydrogel for normal and MRSA infected wound repair.

Large-scale skin damage brings potential risk to patients, such as imbalance of skin homeostasis, inflammation, fluid loss and bacterial infection. Moreover, multidrug resistant bacteria (MDRB) infection is still a great challenge for skin damage repair. Herein, we developed an injectable self-healing bioactive nanoglass hydrogel (FABA) with robust antibacterial and anti-inflammatory ability for normal and Methicillin-resistant Staphylococcus aureus (MRSA) infected skin wound repair. FABA hydrogel was fabricated facilely by the self-crosslinking of F127-CHO (FA) and alendronate sodium (AL)-decorated Si-Ca-Cu nanoglass (BA). FABA hydrogel could significantly inhibit the growth of Staphylococcus aureus, Escherichia coli and MRSA in vitro, while showing good cytocompatibility and hemocompatibility. In addition, FABA hydrogel could inhibit the expression of proinflammatory factor TNF-α and enhance the expression of anti-inflammatory factor IL-4/ IL-10. Based on its versatility, FABA hydrogel could complete wound closure efficiently (75% at day 3 for normal wound, 70% at day 3 for MRSA wound), which was almost 3 times higher than control wound, which was related with the decrease of inflammatory factor in early wound. This work suggested that FABA hydrogel could be a promising dressing for acute and MRSA-infected wound repair.

Development of gold nanoparticles-aptamer nanocomposite for multiplexed analysis of antibiotics and design of molecular logic gates.

The widespread use of antibiotics caused severe problems of antibiotic residues in foodstuffs and water, posing a serious threat to public health and thus urging the development of sensitive, selective, and rapid detection methods for antibiotics. In this study, a fluorescence resonance energy transfer (FRET)-based system is developed for the multiplexed analysis of chloramphenicol (CAP) and streptomycin (Strep) with detection limits of 2.51 and 8.69µg l-1, respectively. The FRET-based system consists of Cy3-tagged anti-CAP aptamer-conjugated gold nanoparticles (AuNPs) (referred to as AuNPs-AptCAP) and Cy5-tagged anti-Strep aptamer-conjugated AuNPs (referred to as AuNPs-AptStrep). In addition, AuNPs-AptCAP and AuNPs-AptStrep have been demonstrated to serve as signal transducers for implementing a series of logic operations such as YES, NOT, INH, OR, (2-4)-Decoder and even more complicated multi-level logic gates (OR-INH). Based on the outputs of logic operations, it could be figured out whether targeted analytes were present or not, thus enabling multiplex sensing and evaluation of pollution status. This proof of concept study might provide a new route for the enhanced sensing performance to distinguish different pollution status as well as the design of molecular mimics of logic elements to demonstrate better applicability.

Electrochemical dopamine sensor based on bi-metallic Co/Zn porphyrin metal-organic framework.

Integrating other metal ions into mono-metallic metal-organic framework (MOF) to form bi-metallic MOF is an effective strategy to enhance the performance of MOFs from the internal structure. In this study, two-dimensional (2D) cobalt/zinc-porphyrin (Co/Zn-TCPP) MOF nanomaterials with different Co/Zn molar ratios were synthesised using a simple surfactant-assisted method, and novel dopamine (DA) sensing methods were constructed based on these materials. The characterisation results showed that all MOF with different Co/Zn molar ratios presented a nanofilm, and the Co and Zn elements were uniformly distributed. All sensors based on CoxZn100-x-TCPP had a certain catalytic performance to DA. Among them, the sensor based on CO25Zn75-TCPP showed the strongest signal response, indicating that the catalytic performance of MOF on DA can be adjusted by changing the Co/Zn molar ratio. The doping of metal ions improves the chemical environment of the pores, and increases the types and spatial arrangement of the active sites of the MOF, which is beneficial to the electron transfer and exchange with DA; Co2+ and Zn2+ active centres have a synergistic promotion effect, so the catalytic activity of MOF is significantly improved. The linear range at the potential of 0.1 V based on Co25Zn75-TCPP for DA was 5 nM-177.8 µM, with a detection limit of 1.67 nM (S/N = 3). The sensor exhibited a good selectivity for detecting DA. This research is expected to provide new ideas and references for constructing high-performance sensing interfaces and platforms.

Voltammetric determination of hydrogen peroxide using AuCu nanoparticles attached on polypyrrole-modified 2D metal-organic framework nanosheets.

AuCu/PPy/Cu-TCPP nanocomposites were synthesized by attaching AuCu nanoparticles to a polypyrrole (PPy)-modified 2D Cu-TCPP metal-organic framework nanosheet; Cu-TCPP can exhibit catalytic activity for the reduction of H2O2. Based on the nanocomposite, a new method for the determination of H2O2 was established. The morphology of the AuCu/PPy/Cu-TCPP was analyzed by transmission electron microscopy. Cu-TCPP exhibited a 2D nanosheet with obvious wrinkles, and a large amount of AuCu was uniformly attached to PPy/Cu-TCPP. The composition and structure were studied by X-ray diffraction, FTIR, and X-ray photoelectron spectroscopy. At the optimal working potential and scan rate of - 0.55 V(vs. SCE) and 100 mV/s, respectively, electrochemical studies indicated that in N2-saturated supporting electrolyte, the method showed good catalytic performance for H2O2, with a detection limit of 6.67 nM (S/N = 3), a linear range of 7.10 µM-24.10 mM, and a sensitivity of 35.0 µA mM-1 cm2. Compared to H2O2 methods based on related materials, this method exhibits a wide linear range, and the detection limit is down to nanomolar. Graphical abstract Schematic presentation of the preparation of AuCu/PPy/Cu-TCPP nanocomposites. AuCu/PPy/Cu-TCPP nanocomposite was prepared by loading gold-copper (AuCu) bimetallic nanoparticles with good catalytic properties on two-dimensional copper (II)-porphyrin (Cu-TCPP) nanosheet metal-organic framework material, whose conductivity was improved by polypyrrole (PPy). A method for the determination of hydrogen peroxide by voltammetric was established.

Non-enzymatic electrochemical hydrogen peroxide sensing using a nanocomposite prepared from silver nanoparticles and copper (II)-porphyrin derived metal-organic framework nanosheets.

A non-enzymatic hydrogen peroxide (H2O2) electrochemical sensor material was prepared from silver nanoparticles and a 2D copper-porphyrin framework (MOF). The structure and morphology of the nanocomposite were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy. The results showed that the MOF has a two-dimensional sheet structure, and a large number of Ag NPs are uniformly attached to it. The MOF also acts as a peroxidase mimic. The sensor has excellent catalytic performance in terms of H2O2 reduction. Figures of merit include (a) an electrochemical sensitivity of 21.6 µA mM-1 cm-2 at a typical working potential of -0.25 V (vs. SCE), (b) a detection limit of 1.2 µM (at S/N = 3), and (c) a linear response range that extends from 3.7 µM to 5.8 mM. Compared to other sensors of the same type, the linear range of the sensor is extended by an order of magnitude. Graphical abstract Silver nanoparticles (Ag NPs) were reduced with sodium borohydride (NaBH4) on the surface of copper(II)-porphyrin (Cu-TCPP) nanosheets prepared with the assistance of polyvinylpyrrolidone (PVP). Their synergistic effect improved the performance of H2O2 sensor fabricated by immobilizing Ag NPs/Cu-TCPP nanocomposites on glassy carbon electrodes (GCE).

CDSP: A Solution for Privacy and Security of Multimedia Information Processing in Industrial Big Data and Internet of Things.

With the widespread nature of wireless internet and internet of things, data have bloomed everywhere. Under the scenario of big data processing, privacy and security concerns become a very important consideration. This work focused on an approach to tackle the privacy and security issue of multimedia data/information in the internet of things domain. A solution based on Cryptographical Digital Signal Processor (CDSP), a Digital Signal Processor (DSP) based platform combined with dedicated instruction extension, has been proposed, to provide both programming flexibility and performance. We have evaluated CDSP, and the results show that the algorithms implemented on CDSP all have good performance. We have also taped out the platform designed for privacy and security concerns of multimedia transferring system based on CDSP. Using TSMC 55 nm technology, it could reach the speed of 360 MHz. Benefiting from its programmability, CDSP can be easily expanded to support more algorithms in this domain.

A ratiometric fluorescent core-shell nanoprobe for sensing and imaging of zinc(II) in living cell and zebrafish.

A zinc(II)-responsive ratiometric fluorescent core-shell nanoprobe (referred to as QPNPs) is described. It consist of an optimized combination of an internal reference dye (TBAP) encapsulated in the core, and a Zn(II)-specific indicator dye (PEIQ) in the shell. The nanoprobe was synthesized via single-step graft copolymerization induced by tert-butyl hydroperoxide at 80 °C. QPNPs exhibit a well-defined core-shell nanostructure and well-resolved dual emissions after photoexcitation at 380 nm. After exposure to Zn(II), the QPNPs display a green fluorescence peaking at ~500 nm that increases with the concentration of Zn(II), while the pink fluorescence of the porphine-derived reference dye peaking at ~650 nm remains unchanged. This results in color change from pink to green and thus enables Zn(II) to be detected both spectroscopically and with bare eyes. Zn(II) can be quantified with a 3.1 nM detection limit. The core-shell structured nanoprobe was also applied to real-time imaging of Zn(II) in living HeLa cells and in zebrafish. This work establishes a reliable approach to synthesize ratiometric fluorescent nanoprobes. It enables such nanoprobes to be prepared also by those not skilled in nanomaterial synthesis. Graphical abstract A zinc(II)-responsive core-shell nanoprobe (referred to as QPNP) is synthesized via single-step graft copolymerization. Zn(II) can be quantitated with a 3.1 nM detection limit by the QPNPs through ratiometric fluorescence strategy (PEIQ as the Zn(II) indicator and TBAP as the reference dye).

99m Tc-labeled DTPA-colchicine dimer with improved tumor uptake.

This work reports the synthesis, radiolabeling, and biological studies of 99m Tc-diethylene triamine pentaacetic acid (DTPA)-colchicine dimer in tumor-bearing mice. The novel colchicine dimer was successfully synthesized by conjugation of DTPA to 2 colchicine biomolecules. The ligand could be labeled by 99m Tc in high yield to get 99m Tc-DTPA-colchicine dimer, which was hydrophilic and stable at room temperature. Biodistribution and imaging studies in tumor-bearing mice showed that 99m Tc-DTPA-colchicine dimer accumulated in the tumor with improved uptake and retention. The results indicate the need for synthetic modification of the parent colchicine derivative and the 99m Tc-chelate with a view to improve the tumor-targeting efficacy and in vivo kinetic profiles.

[Re-sequencing and assembly of chicken T cell receptor gamma locus].

The genomic organization of the animal T cell receptor (TCR) loci is characterized by different gene families with high homology, and it is quite difficult to obtain accurate gene sequences and arrangements of these gene families. In this study, we identified the location of chicken TCR gamma chain (TCRγ or TRG) genes by comparing those TRG gene sequences with the chicken reference genome, and the corresponding bacterial artificial chromosome (BAC) clone, CH261-174P24, was chosen for further high-throughput DNA re-sequencing and assembly. As a result, a draft genome assembly containing ten scaffolds was obtained, which almost covered the chicken TRG gene locus and the flanking regions. Subsequently, the internal structure of these scaffolds was confirmed by PCR amplification and Sanger sequencing. Our analysis corrected two errors in the sequence-one near a TRG variable gene and one close to a gap, respectively, and several errors in the TRG variable genes in the chicken reference genome. In conclusion, our work has partially corrected the erroneously assembled sequences of the TRG gene locus in the chicken reference genome and thus provides a new method for genome sequence analysis of chicken TRA/D and TRB gene loci.

Sprayable self-assembly multifunctional bioactive poly(ferulic acid) hydrogel for rapid MRSA infected wound repair.

The repair of methicillin-resistant staphylococcus aureus (MRSA) infected wounds remains a serious challenge. Development of multifunctional bioactive hydrogels has shown promising potential in treating MRSA wound. Ferulic acid has special bioactivities including antioxidant antiinflammation antibacterial capacities but limited in lack of engineering strategy for efficient treatment of MRSA infected wound. Herein, we developed a multifunctional bioactive poly(ferulic acid) copolymer (FPFA) for treating MRSA infected wound. FPFA could be self-assembled into hydrogel under body temperature and demonstrated the injectable, sprayable, self-healing, anti-inflammatory, antioxidant, and angiogenic activity. FPFA hydrogel also showed the good cytocompatibility, efficiently enhanced the endothelial cell migration, scavenged intracellular reactive oxygen species (ROS), inhibited the expression of inflammatory factors and enhanced the in vitro angiogenesis. The MRSA-infected wound model showed that FPFA could significantly inhibit the MRSA infection and excess inflammation, reinforce the angiogenesis, accelerate wound healing and skin tissue regeneration.

Study on Process Parameters of Magnetron Sputtering Titanium Coating in Deep Porous Structures.

In order to improve the energy conversion efficiency and power density of the tritium-powered betavoltaic battery, titanium was deposited on the inner surface of the deep porous three-dimensional structure semiconductor as a tritium absorption material. Therefore, magnetron sputtering technology was used to explore the parameters of titanium coating on the inner surface of a deep porous semiconductor. First, the effects of argon pressure and sputtering power on the properties of titanium films were studied. The properties of the titanium films were characterized by a scanning electron microscope and an atomic force microscope. The optimized sputtering parameters were obtained as follows: argon pressure of 0.5 Pa and sputtering power of 80 W. Based on this parameter, the background vacuum and coating angle were changed, and the titanium film was coated in the deep porous structure. Energy dispersive spectrometry line scan and surface scan were used to analyze the coating results, which showed that these two parameters directly affected the content of titanium in the channel, and the area of titanium in the channel structure accounted for more than 50% under each test condition.

Bioactive poly(salicylic acid)-poly(citric acid) scaffolds improve diabetic wound repair via regulating HIF-1α, Nrf2 and macrophage.

Diabetic wounds environment is over-oxidized, over-inflammatory, leading to difficulties in regenerating blood vessels, and retardation of healing in diabetic wounds. Therefore, diabetic wounds can be treated from the perspective of scavenging oxidative free radicals and reducing the level of inflammation. Herein, we report a bioactive poly(salicylic acid)-poly(citric acid) (FPSa-PCG) hydrogel for diabetic wound repair. The FPSa-PCG hydrogel shows abilities of antioxidation, anti-inflammation, and regulation of macrophage phenotype. The FPSa-PCG hydrogel showed good biocompatibility, and obtain the abilities of promotion of macrophages migration, reduction of ROS generation, suppression of the M1-type macrophage polarization. FPSa and PCG could synergistically enhance the angiogenesis through upregulating the mRNA expression of HIF1Α, VEGF, and CD31 in endothelial cells and reduce the ROS level of macrophages through upregulating the mRNA expression of Nrf2. The in vivo diabetic wound model confirmed the promoting effect of FPSa-PCG hydrogel on wound closure in diabetes. The further studies found that FPSa-PCG hydrogel could induce the CD31 protein expression in the subcutaneous tissue and inhibit the TNF-a protein expression. This work shows that the simple composition FPSa-PCG hydrogel has a promising therapeutic potential in the treatment of diabetic wounds.

Intrinsically bioactive multifunctional Poly(citrate-curcumin) for rapid lung injury and MRSA infection therapy.

Dysregulated inflammation after trauma or infection could result in the further disease and delayed tissue reconstruction. The conventional anti-inflammatory drug treatment suffers to the poor bioavailability and side effects. Herein, we developed an amphiphilic multifunctional poly (citrate-polyglycol-curcumin) (PCGC) nano oligomer with the robust anti-inflammatory activity for treating acute lung injury (ALI) and Methicillin-resistant staphylococcus aureus (MRSA) infected wound. PCGC demonstrated the sustained curcumin release, inherent photoluminescence, good cellular compatibility, hemocompatibility, robust antioxidant activity and enhanced cellular uptake. PCGC could efficiently scavenge nitrogen-based free radicals, oxygen-based free radicals, and intracellular oxygen species, enhance the endothelial cell migration and reduce the expression of pro-inflammatory factors through the NF-κB signal pathway. Combined the anti-inflammation and antioxidant properties, PCGC can shortened the inflammatory process. In animal model of ALI, PCGC was able to reduce the pulmonary edema, bronchial cell infiltration, and lung inflammation, while exhibiting rapid metabolic behavior in vivo. The MRSA-infection wound model showed that PCGC significantly reduced the expression of pro-inflammatory factors, promoted the angiogenesis and accelerated the wound healing. The transcriptome sequencing and molecular mechanism studies further demonstrated that PCGC could inhibit multiple inflammatory related pathways including TNFAIP3, IL-15RA, NF-κB. This work demonstrates that PCGC is efficient in resolving inflammation and promotes the prospect of application in inflammatory diseases as the drug-loaded therapeutic system.

Injectable Bioactive Antioxidative One-Component Polycitrate Hydrogel with Anti-Inflammatory Effects for Osteoarthritis Alleviation and Cartilage Protection.

Chronic inflammation in osteoarthritis (OA) can destroy the cartilage extracellular matrix (ECM), causing cartilage damage and further exacerbating the inflammation. Effective regulation of the inflammatory microenvironment has important clinical significance for OA alleviation and cartilage protection. Polycitrate-based polymers have good antioxidant and anti-inflammatory abilities but cannot self-polymerize to form hydrogels. Herein, a one-component multifunctional polycitrate-based (PCCGA) hydrogel for OA alleviation and cartilage protection is reported. The PCCGA hydrogel is prepared using only the PCCGA polymer by self-polymerization and exhibits multifunctional properties such as injectability, adhesion, controllable pore size and elasticity, self-healing ability, and photoluminescence. Moreover, the PCCGA hydrogel exhibits good biocompatibility, biodegradability, antioxidation by scavenging intracellular reactive oxygen species, and anti-inflammatory ability by downregulating the expression of proinflammatory cytokines and promoting the proliferation and migration of stem cells. In vivo results from an OA rat model show that the PCCGA hydrogel can effectively alleviate OA and protect the cartilage by restoring uniform articular surface and cartilage ECM levels, as well as inhibiting cartilage resorption and matrix metalloproteinase-13 levels. These results indicate that the PCCGA hydrogel, as a novel bioactive material, is an effective strategy for OA treatment and has broad application prospects in inflammation-related biomedicine.

Highly Bioactive MXene-M2-Exosome Nanocomposites Promote Angiogenic Diabetic Wound Repair through Reconstructing High Glucose-Derived Immune Inhibition.

The repair of diabetic wounds remains challenging, primarily due to the high-glucose-derived immune inhibition which often leads to the excessive inflammatory response, impaired angiogenesis, and heightened susceptibility to infection. However, the means to reduce the immunosuppression and regulate the conversion of M2 phenotype macrophages under a high-glucose microenvironment using advanced biomaterials for diabetic wounds are not yet fully understood. Herein, we report two-dimensional carbide (MXene)-M2 macrophage exosome (Exo) nanohybrids (FM-Exo) for promoting diabetic wound repair by overcoming the high-glucose-derived immune inhibition. FM-Exo showed the sustained release of M2 macrophage-derived exosomes (M2-Exo) up to 7 days and exhibited broad-spectrum antibacterial activity. In the high-glucose microenvironment, relative to the single Exo, FM-Exo could significantly induce the optimized M2a/M2c polarization ratio of macrophages by activating the PI3K/Akt signaling pathway, promoting the proliferation, migration of fibroblasts, and angiogenic ability of endothelial cells. In the diabetic full-thickness wound model, FM-Exo effectively regulated the polarization status of macrophages and promoted their transition to the M2 phenotype, thereby inhibiting inflammation, promoting angiogenesis through VEGF secretion, and improving proper collagen deposition. As a result, the healing process was accelerated, leading to a better healing outcome with reduced scarring. Therefore, this study introduced a promising approach to address diabetic wounds by developing bioactive nanomaterials to regulate immune inhibition in a high-glucose environment.

Multifunctional MXene-Based Bioactive Materials for Integrated Regeneration Therapy.

The reconstruction engineering of tissue defects accompanied by major diseases including cancer, infection, and inflammation is one of the important challenges in clinical medicine. The development of innovative tissue engineering strategies such as multifunctional bioactive materials presents a great potential to overcome the challenge of disease-impaired tissue regeneration. As the major representative of two-dimensional nanomaterials, MXenes have shown multifunctional physicochemical properties and have been diffusely studied as multimodal nanoplatforms in the field of biomedicine. This review summarized the recent advances in the multifunctional properties of MXenes and integrated regeneration-therapy applications of MXene-based biomaterials, including tissue regeneration-tumor therapy, tissue regeneration-infection therapy, and tissue regeneration-inflammation therapy. MXenes have been recognized as good candidates for promoting tissue regeneration and treating diseases through photothermal therapy, regulating cell behavior, and drug and gene delivery. The current challenges and future perspectives of MXene-based biomaterials in integrated regeneration-therapy are also discussed well in this review. In summary, MXene-based biomaterials have shown promising potential for integrated tissue regeneration and disease treatment due to their favorable physicochemical properties and bioactive functions. However, there are still many obstacles and challenges that must be addressed for the regeneration-therapy applications of MXene-based biomaterials, including understanding the bioactive mechanism, ensuring long-term biosafety, and improving their targeting therapy capacity.

Single-Component Self-Healing Antibacterial Anti-Inflammatory Intracellular-Antioxidative Poly(itaconic acid-pluronic) Hydrogel for Rapid Repair of MRSA-Impaired Wound.

The rapid healing and repair of multidrug-resistant bacteria infected wound is still a challenge in the field of wound surgery. It is an effective strategy to develop multifunctional bioactive biomaterials with anti-infection therapy and promoting tissue regeneration. However, most of conventional multifunctional wound healing biomaterials possess the complicated composition and fabrication procedure, which may limit their clinical transformation. Herein, we report a single-component multifunctional bioactive self-healing scaffold (itaconic acid-pluronic-itaconic acid) (FIA) with robust antibacterial antioxidant anti-inflammatory bioactivity for treating methicillin-resistant Staphylococcus aureus (MRSA) impaired wound. FIA scaffolds exhibited the temperature-responsive sol-gel behavior, good injectability, and broad-spectrum antibacterial activity (100% inhibition rate against S. aureus, E. coli, and MRSA). FIA possessed favorable hemocompatibility and cell compatibility and even stimulated the cellular proliferation. FIA could efficiently scavenge the intracellular reactive oxygen species (ROS), decrease the inflammation factors expression, promote endotheliocyte migration and blood tube formation, and reduce the M1 phenotype of macrophages in vitro. FIA could significantly clear the MRSA infection, speed up the MRSA-infected wound healing and rapid formation of the normal epithelial layer and skin appendages. This work may provide a simple and efficient multifunctional bioactive biomaterial strategy for overcoming the challenge of the MRSA-impaired wound.

Bioactive MXene Promoting Angiogenesis and Skeletal Muscle Regeneration through Regulating M2 Polarization and Oxidation Stress.

Complete repair of skeletal muscles caused by severe mechanical damage and muscle-related diseases remains a challenge. 2D Ti3 C2 Tx (MXene) possesses special photoelectromagnetic properties and has attracted considerable attention in materials science and engineering. However, the bioactive properties and potential mechanism of MXene in tissue engineering, especially in skeletal muscle regeneration, are unclear. Herein, the antioxidation and anti-inflammation activities of MXene and its effects on myogenic differentiation and regeneration of skeletal muscle in vivo are investigated. In vitro studies have shown that MXene has excellent antioxidation and anti-inflammatory properties, and promotes myogenic differentiation and angiogenesis. MXene can remove excess reactive oxygen species in macrophage cells to alleviate oxidative stress and induce the transformation of M1 macrophages into M2 macrophages to reduce excessive inflammation, which can significantly promote the proliferation and differentiation of myoblasts, as well as the proliferation, migration, and tube formation of endothelial cells. Animal experiments with rat tibial anterior muscle defects show that MXene can promote angiogenesis, muscle fiber formation, and skeletal muscle regeneration by regulating the cell microenvironment through anti-inflammatory and antioxidant pathways. The findings suggest that MXene can be used as a multifunctional bioactive material to enhance tissue regeneration through robust antioxidation, anti-inflammation, and angiogenesis activities.

BSA-templated synthesis of Ir/Gd bimetallic oxide nanotheranostics for MR/CT imaging-guided photothermal and photodynamic synergistic therapy.

Precision medicine urges the development of theranostics which can efficiently integrate precise diagnosis and effective therapy. In this study, a facile synthesis of Ir/Gd bimetallic oxide nanotheranostics (termed BSA@Gd2O3/IrO2 NPs) with good biocompatibility was demonstrated using a biomineralization method where bovine serum albumin (BSA) served as a versatile template. BSA@Gd2O3/IrO2 NPs exhibited high longitudinal relaxivity (5.2 mM-1 s-1) and X-ray absorption capability (14.5 Hu mM-1), illustrating them to be a good contrast agent for magnetic resonance (MR) and computed tomography (CT) dual-modal imaging. Moreover, BSA@Gd2O3/IrO2 NPs can act as not only a photothermal conversion agent with ultrahigh efficiency (66.7%) as well as a good photosensitizer, but also an effective catalase to decompose endogenous H2O2 to produce O2, thus relieving hypoxia and enhancing the phototherapeutic effect. Both in vitro and in vivo experiments demonstrated the high effectiveness of BSA@Gd2O3/IrO2 NPs in MR/CT dual-modal imaging and photothermal and photodynamic synergistic tumor treatments. This work sheds new light on the development of versatile nanotheranostic systems using mild and robust biomineralization methods.