Small Au nanoparticles to be modified with decavanadate for sensitive and stable SERS detection

Surface enhanced Raman spectroscopy (SERS) has been a powerful vibrational optical spectroscopic technique for trace determination. And the application and promotion of SERS technology are closely related to plasmonic substrates. To combine the distinct electronic properties of polyoxovanadates with the plasmonic properties of Au NPs, the small cit-Au NPs (reduced by sodium citrate) was modified with decavanadate (V10) via ligand displacement. The structure of V10 was controlled by pH adjustment. X-ray photoelectron spectroscopy (XPS) and SERS were introduced for studying interactions of V10 with the surface of Au NPs. Compared with cit-Au NPs, V10-Au NPs owned higher absolute value of zeta potential and presented greater stability in CH3OH/H2O (V/V = 1:10) solvent environment. Even after 60 min of soaking, the V10-Au NPs still exhibited a typical coffee ring effect during the evaporation process with SERS enhancement. The stability of V10-Au NPs (in a solution with pH 4.8) was tested over a period of 5 days to indicate their ability to maintain SERS activity. Moreover, the V10-Au NPs also showed great sensitivity for cationic dye molecules and antibiotics, and the detection levels could be as low as μg⋅L-1. This study lays the foundation for the screening low-concentration cations in mixed solutions and monitoring the morphological changes of polyoxometalates during their application via SERS technology.

Theoretical understanding of the ABC persistent structure in strongly H-bonded systems: Computational analysis of phosphonic and bis-(heptafluoropropyl) phosphonic acid dimers in gas phase

Hydrogen bonds (HBs) that involve direct interaction with fluorine have been the subject of considerable research; however, the indirect influence of fluorine on the dynamics of the strongly hydrogen bonded systems as well as on neighboring donor and acceptor molecules remains inadequately understood and challenging to anticipate. In this paper, we present a theoretical analysis of the infrared absorption spectra of two different phosphinic acids in the gaseous state, R2POOH, namely the phosphinic acid (where R = H2 ) and the bis-(heptafluoropropyl) phosphonic acid (where R = C3F7). within the spectral range 750-3500 cm-1 at a temperature domain of 345-500 K (Aslin et al., 2002). The equilibrium between the dimers and monomers, giving rise to the stability of the recorded spectra, is experimentally obtained at T =500 K. The resulting band has the characteristic of an ABC structure (Hadzi structure), which is typical to the spectra of structures characterized by exceptionally strong hydrogen bonds in solution and in crystal phase. The experimental spectra is contrasted with the one computationally determined using a theoretical model that congregates, Fermi resonances, Davydov coupling, the theory of strong anharmonic coupling and the effect of the reversible action of the medium on the anharmonic vibrational modes altogether with the same approach dealing with Kubo's linear response theory. A satisfactory superimposition between the numerically generated spectra and the experimental infrared absorption spectra is elucidated. The theoretical analysis is performed through the examination of the effect of the commonly employed theories and approximations in order to illuminate how to numerically simulate the ABC structure. The method offers a clear explanation for the Hadzi structure's formation by demonstrating that the BC diad is produced by the Fermi resonance mechanism, while the peak A is caused by the Davydov coupling mechanism. The clarification of the dynamics and the function of fluorine in hydrogen bonding could signify a notable progress in creating a comprehensive simulation tool designed to forecast the infrared absorption bands of compounds exhibiting strong and very strong hydrogen bonds, along with their interactions and affinity with DNA polymerase. This tool might make it possible to conduct methodical research on the intricate relationship between fluorine's direct and indirect effects on the properties of physiologically active compounds and how they interact with drug-like targets.

Photophysical behaviour and sub-cellular specificity of a pyrene-benzothazolium imaging dye: A study of regio-effect

Pyrene-based small-molecule fluorescent dyes have been widely used in biomedical imaging and sensing applications. Among them, pyrene-based π-acceptor (π-A) type probes are an important class of fluorescent dyes due to their ability to produce a large Stokes' shift (Δλ >100 nm) by strong intramolecular charge transfer (ICT) process. In this work, a pyrene-benzothiazolium-based π-A probe (ETP-2) was synthesized in good yield to study its imaging applications while comparing with previously developed regio-isomer ETP-1. ETP-2 exhibited a large Stokes shift (Δλ ≈100-150 nm) and a bright red-emission (λem ≈610-630 nm) due to strong intramolecular charge transfer (ICT) effect. The behaviour of the two regioisomers (ETP-2 and ETP-1) were studied by different photophysical methods including optical spectroscopy, transient absorption (TA) spectroscopy, fluorescence lifetime measurements, and low-temperature fluorescence. Sub-cellular specificity of ETP-2 was studied with several fluorescent markers (mitochondria, lysosome, nucleus, endoplasmic reticulum, and Golgi) and ETP-2 exhibited an exceptional lysosome specificity in A-172 cells (Pearson's correlation coefficient calc. ≈0.9). Fluorescence confocal microscopy imaging and fluorescence spectroscopy-based studies indicated strong evidence to support possible localization of ETP-2 into the membrane regions of the lysosomes.

Quantitative detection of potassium chloride solutions at different concentrations using terahertz waves

Terahertz detection, utilizing electromagnetic waves within the terahertz spectral band, offers a sophisticated approach for the analysis and identification of materials. This technique capitalizes on the distinctive resonant interactions between terahertz waves and the vibrational modes of various non-polar substances and biochemical entities. A notable challenge arises in the terahertz time-domain spectroscopy (THz-TDS) when applied to water-rich samples, owing to the significant absorption characteristics of water molecules at these frequencies. Although various methodologies exist for the detection of potassium chloride, a common substance with extensive applications, its analysis using THz-TDS, particularly in aqueous solutions, remains unexplored in literature. This investigation delineates the terahertz spectral behavior of potassium chloride in powdered form and extends to evaluate aqueous solutions with concentrations ranging from 3 to 60 mmol/L. The findings indicate a pronounced absorption peak within the terahertz range for potassium chloride solutions, which progressively lowers in intensity as the concentration increases. Consequently, THz-TDS emerges as a swift, precise, non-invasive, and safe modality for the quantification of potassium chloride in solutions.

Metal-free antioxidant nanozyme incorporating bioactive hydrogel as an antioxidant scaffold for accelerating bone reconstruction

Oxidative stress at bone defect sites mediates inflammation and even osteoblast apoptosis, severely hindering the repair process. While current antioxidant bone tissue engineering (BTE) scaffolds lack broad-spectrum reactive oxygen species (ROS) scavenging capability and structure-activity elucidation. Herein, we report a three-dimensional nitrogen-doped carbon antioxidant nanozyme (ZIFC) derived from metal-organic frameworks, which exhibits cascading superoxide dismutase- and catalase-like activities, along with the ability to scavenge other harmful free radicals. Through the experimental studies and theoretical calculations, we reveal that the catalase-like activity arises from the synergistic catalytic interaction between graphitized pyridinic nitrogen and its adjacent carbon atom. Moreover, hybrid double network hydrogel integrated with ZIFC is utilized to construct composite scaffold (Gel/ZIFC) by 3D printing. In vivo transcriptome analysis confirms that Gel/ZIFC can rapidly activate antioxidant defense system and suppress local inflammation under oxidative stress microenvironment, thereby protecting cells from oxidative damage. Subsequently, owing to the unique osteoinductive property of carbon nanomaterials and the osteoconductive property of 3D-printed scaffold, Gel/ZIFC composite scaffold exhibits desirable bone repair efficacy. The elucidation of structure-activity relationship and therapeutic mechanism provides new insights and guidance for devising antioxidant BTE scaffolds, and demonstrates their feasibility for clinical application.

Unlocking the bioremediation potential of adapted Desulfovibrio desulfuricans in acidic low-temperature U-contaminated groundwater

Addressing the global challenge of uranium (U)-contaminated groundwater requires innovative bioremediation strategies. This study investigates Desulfovibrio desulfuricans, a neutrophilic and mesophilic sulfate-reducing bacteria (SRB) strain optimized for low-temperature (15 °C) and acidic (initial pH 4) conditions, to validate its bioaugmentation potential for uranium decontamination in groundwater. Our research aimed to assess its efficacy in treating U-contaminated groundwater and elucidate the optimal growth conditions for this strain in acidic and sulfate-enriched environments. We found that D. desulfuricans was phylogenetically distinct from the native microbial community in acidic U-contaminated groundwater, while it maintained appreciable activity in sulfate reduction under contaminated groundwater conditions after accumulation. Acid-tolerant D. desulfuricans removed 75.87 % of uranium and 30.64 % of sulfate from acidic U-contaminated groundwater (pH 4.0) at 15 °C within 14 days. Furthermore, we explored the optimal sulfate concentration for bacterial growth, which was found to be 2000 mg/L, and an elevated Fe2+ concentration from 100 to 1000 mg/L increasingly stimulated sulfate-reducing activity. These findings provide a novel insight into the application of neutrophilic and mesophilic SRB in bioremediation of acidic and low-temperature groundwater after accumulation and underscore the feasibility of bioremediation by using exogenously pure SRB.

Selective and iron-independent ferroptosis in cancer cells induced by manipulation of mitochondrial fatty acid oxidation

Despite the promise of ferroptosis in cancer therapy, selectively inducing robust ferroptosis in cancer cells remains a significant challenge. In this study, manipulation of fatty acids β-oxidation (FAO) by combination of mild photodynamic therapy (PDT) and inhibition of triglycerides (TGs) synthesis was found to induce robust and iron-independent ferroptosis in cancer cells with dysregulated lipid metabolism for the first time. To achieve that, TGs synthesis inhibitor of xanthohumol (Xan) and FAO initiator of tetrakis (4-carboxyphenyl) porphyrin (TCPP) were co-delivered by a nanoplexes composed of pH-responsive amphiphilic lipopeptide C18-pHis10 and DSPE-PEG2000. TCPP was found to rapidly increase the intracellular ROS under laser irradiation without inducing antioxidant response and apoptosis, activating the AMPK in cancer cells and accelerating mitochondrial FAO. Xan fueled the mitochondrial FAO with substrates by suppressing the conversion of fatty acids (FAs) to TGs. This also led to augmented intracellular polyunsaturated fatty acids (PUFAs) and PUFAs-phospholipids levels, increasing the intrinsic susceptibility of cancer cells to lipid peroxidization. As a result, the excessive ROS generated from the sustained mitochondrial FAO caused remarkably lipid peroxidation and ultimately ferroptosis. Collectively, our study provides a new approach to selectively induce iron-independent ferroptosis in cancer cells by taking advantage of dysregulated lipid metabolism.

Acid and phosphatase-triggered release and trapping of a prodrug on cancer cell enhance its chemotherapy

Using anticancer drug-encapsulated nanocarriers to actively target tumors is a promising chemotherapy strategy. Nevertheless, premature release of the drugs in tumor microenvironment (TME) or low tumor targeting efficiency of the nanocarriers significantly reduces its therapeutic efficiency. Herein, we propose a release-and-trapping strategy that significantly enhances the chemotherapeutic efficiency of an anticancer drug camptothecin. TME acid triggers the release of its prodrug from the nanocarrier and thereafter phosphatase instructs the prodrug to form hydrogel to trap the nanocarrier on cancer cell membrane. As trapped nanocarrier facilitates cell uptake of the prodrug and its intracellular carboxylesterase-mediated hydrolysis to release camptothecin. In vitro studies showed that the prodrug release from nanocarrier was maximized at pH 6.5. In tumor-bearing mice, our release-and-trapping strategy significantly prolonged the retention of the nanocarrier in tumor and significantly enhanced the anticancer efficacy of camptothecin. We propose that our release-and-trapping strategy be applied for more efficient cancer treatment in the future.

All-in-one design of titanium-based dental implant systems for enhanced soft and hard tissue integration

Enhancing the sealing between titanium abutment and surrounding soft tissue is crucial for preventing peri-implantitis. Meanwhile, exploring non-invasive antibacterial strategies as alternatives for traditional antibiotic therapy is central to improving the effect of peri-implantitis treatment. Furthermore, facilitating effective integration between titanium implant and osteoporotic bone is the cornerstone for ensuring long-term implant stability in patients with osteoporosis. In light of this, this work innovatively constructed multifunctional vertical graphene-based coatings on titanium implants and abutments using plasma-enhanced chemical vapor deposition technology. The results demonstrated that the vertical graphene coatings promoted soft tissue sealing and exhibited inherent antibacterial activities with the bacteriostasis rates of 65.60 % against Staphylococcus aureus (S. aureus) and 43.89 % against Escherichia coli (E. coli) in vitro which could prevent early infections. Moreover, vertical graphene coatings presented photothermal antibacterial effects with the antibacterial rates of 99.99 % and 95.83 % for S. aureus in vitro and in vivo, respectively, and 92.23 % for E. coli in vitro under near-infrared irradiation, which provided a non-invasive and highly effective treatment option for peri-implantitis. Furthermore, teriparatide acetate was loaded on vertical graphene coatings which enhanced osseointegration between titanium implants and osteoporotic bone. By comprehensively considering the critical functional requirements of dental implants and abutments, this work meticulously designed vertical graphene-based coatings on titanium dental implant systems for soft and hard tissue integration. This innovative design demonstrates immense application potential, especially for dental implant restoration in patients with osteoporosis.

Imidazole-triggered in situ fluorescence reaction system for quantitatively determination of dopamine from multiple sources

Highly selective and sensitive determination of dopamine (DA) from multiple sources remains a persistent and significant challenge. Here, we develop an imidazole-triggered in situ fluorescence reaction system for highly selective and sensitive determination of DA from various sources (human, horse, dog, rabbit, and mouse). The system operates by catalyzing the oxidation of DA with 1,5-Dihydroxynaphthalene (1,5-DHA) through a Lewis base formed by imidazole, leading to the rapid generation of yellow azamonardine fluorescent compounds (AFC). Notably, the system demonstrates minimal background noise and a high signal-to-noise ratio of up to 300-fold with a determination limit of 33.33 pM, making it 10-100 times more sensitive than conventional enzyme-linked immunosorbent assay (ELISA) methods. Moreover, selectivity tests reveal that our system can effectively distinguish between several common interfering substances, even at concentrations as low as 10 nM. The developed system shows promising results in detecting DA from diverse sources (humans, horses, dogs, rabbits, and mice), including urine samples from clinical patients, exhibiting good agreement with traditional ELISA kits. Therefore, the established in situ fluorescence reaction system holds great potential for the determination of DA-related disorders due to its impressive analytical capabilities.

Fluorescence anisotropy (FA) of anionic dyes bound to ionic and zwitterionic micelles

Anionic fluorescein and 8-hydroxy-1,3,6-pyrenetrisulfonate (POH), bind to cationic and zwitterionic micelles, experience hindered rotation and exhibit fluorescence anisotropy (FA). Fluorescein emits three lines from its dianion, carboxylate, and phenolate forms. POH emissions are from excited POH* and its deprotonated form, PO-. Fluorescence was excited by vertically polarized (V) light. Spectra recorded with vertical (IVV) and horizontal (IVH) polarizers in the emitted beam were corrected for instrument response and polarization bias. Corrected line shapes were fit to Gaussians availing the computationally derived second harmonic for better fit precision. FA of the individual forms of the same dye was calculated from the IVV and IVH intensities of each component line. For fluorescein, FA phenolate > carboxylate > dianion and FA PO-> POH*. Micelle-bound dye conformations, consistent with this order, are presented. Distinguishing between FA of different forms is novel and significant to elucidation of dye-host interactions.

Dynamic hydrogels for biofabrication: A review

Reversibly crosslinked dynamic hydrogels have emerged as a significant material platform for biomedical applications owing to their distinctive time-dependent characteristics, including shear-thinning, self-healing, stress relaxation, and creep. These physical properties permit the use of dynamic hydrogels as injectable carriers or three-dimensional printable bioinks. It is noteworthy that matrix dynamics can serve as physical cues that stimulate cellular processes. Therefore, dynamic hydrogels are preferred for tissue engineering and biofabrication, which seek to create functional tissue constructs that require regulation of cellular processes. This review summarizes the critical biophysical properties of dynamic hydrogels, various cellular processes and related mechanisms triggered by hydrogel dynamics, particularly in three-dimensional culture scenarios. Subsequently, we present an overview of advanced biofabrication techniques, particularly 3D bioprinting, of dynamic hydrogels for the large-scale production of tissue and organ engineering models. This review presents an overview of the strategies that can be used to expand the range of applications of dynamic hydrogels in biofabrication, while also addressing the challenges and opportunities that arise in the field. This review highlights the importance of matrix dynamics in regulating cellular processes and elucidates strategies for leveraging them in the context of biofabrication.

Nitrogen mono-doping of graphene and co-doping with group 14 as a sensor for diisobutyl phthalate: Insight from a computational study

Diisobutyl phthalate (DIBP) is a highly toxic plasticizer found in edible consumer products and industrial products. It affects the male reproductive system, bioaccumulates in water, and poses health risks. Given its widespread occurrence, designing novel sensor materials for sensing of DIBP is necessary for environmental and health safety. In this research, density functional theory (DFT) at the DFT/MN15/LanL2DZ level was employed to study the structural analysis, electronic properties, visual studies, and sensor mechanisms of modified graphene systems for the detection of diisobutyl pththalate (DIBP). An increase in energy gap values was observed for all studied systems on complexation with gas molecules, which depicted the stable properties of the system. The electronic properties revealed that upon adsorption, the DIBP-Sn-N@GP energy gap was the smallest at 2.778 eV, which indicates great conductivity. The adsorption energy showed that chemisorption occurred in the studied systems. DIBP-Si-N@GP showed the strongest adsorption energy of -18.171 eV, while DIBP-N@GP showed weak chemisorption of -0.914 eV. According to the UV-visible spectrum, DIBP-Ge-N@GP has the greatest peak at a wavelength of 1979.79 nm in the first excited state, corresponding to the H-1→L+2 transition. The sensor mechanism showed that among the tested surfaces, DIBP-Si-N@GP showed the best sensing properties and can be considered good gas sensor materials, attributed to its highest adsorption energy, stabilization energy, and charge transfer values with the lowest back donation energy value.

Ultrasound-switchable piezoelectric BiVO4/fullerene heterostructure for on-demand ROS modulation in MRSA-infected diabetic wound healing

Persistent microbial infections and excessive reactive oxygen species (ROS) accumulation severely impede diabetic wound healing. Herein, we developed an ultrasound-switchable BiVO4/fullerene piezoelectric heterostructure via a one-pot solvothermal method, enabling on-demand transition between bactericidal action and ROS scavenging for treating infected diabetic wounds. Under 8-min ultrasound (US) irradiation, the heterojunction sonosensitizer leveraged piezoelectric polarization to generate substantial ROS in real-time through a narrowed energy band gap and enhanced charge carrier separation and migration efficiency, resulting in the disruption of bacterial membrane integrity and 99.9 % eradication of methicillin-resistant Staphylococcus aureus (MRSA). Upon US withdrawal, the sonosensitizer spontaneously transitioned to an antioxidative state through fullerene-mediated ROS scavenging, effectively neutralizing excess ROS and restoring cellular redox balance. In an MRSA-infected diabetic wound model, this ultrasound-responsive duality effectively suppressed bacterial proliferation, reduced inflammation, enhanced angiogenesis, and ultimately accelerated wound healing within 14 days. This ultrasound-switchable therapeutic strategy offers promising insights for managing drug-resistant infections and other ROS-mediated biomedical challenges.

M1-macrophage membrane-camouflaged nanoframeworks activate multiple immunity via calcium overload and photo-sonosensitization

Immunotherapy is a powerful weapon for inhibiting tumor metastasis, while its efficacy is significantly compromised in immunosuppressive tumor microenvironment (TME). To reverse TME, this work has developed biomimetic nanoframeworks with calcium overload and photo-sonosensitization capacity to activate multiple immunities for metastasis inhibition. The biomimetic nanoframeworks were prepared by the assembly of Ca2+ ions and Protoporphyrin IX (PpIX) into nanoframeworks (Ca-PpIX), and the encapsulation of M1 macrophage membrane (Ca-PpIX@M). They exhibit pH-dependent Ca2+ ions release, 1O2 generation and photothermal conversion under external near-infrared light and ultrasound stimuli. The Ca2+-overload and elevated 1O2 cause oxidative stress within cells, leading to efficient mitochondrial dysfunction. Successively, the mitochondrial dysfunction induces a reduction in adenosine triphosphate (ATP) levels to inhibit the HSP90 expression, improving photothermal ablation's efficacy. The photo-sonosensitization has the ability to repolarize macrophages with the ratio of M1/M2 macrophage increasing from 0.25 to 2.45, which is better than monoactivation. Importantly, the Ca-PpIX@M also can induce the process of immunogenic cell death, resulting in the maturation of dendritic cells (30.2 %) and activation of cytotoxic (12.4 %) and helper T cells (19.7 %), thereby enhancing antitumor immunity in vivo. As a result, tumor growth and metastasis have been significantly inhibited. This work offers insights into developing biomimetic nanoframeworks to reverse TME for activating multiple immunity.

Hydrogen generators-protected mesenchymal stem cells reverse articular redox imbalance-induced immune dysfunction for osteoarthritis treatment

Stem cell therapy has revolutionized the management of osteoarthritis (OA), but the articular dysregulated redox status diminishes cell engraftment efficiency and disrupts immune homeostasis, therefore compromising the overall therapeutic efficacy. Here, we present hydrogen (H2) generators-backpacked mesenchymal stem cells (MSCs) which preserve the biological functions and survival of transplanted cells and reverse articular immune dysfunction, mitigating OA. Specifically, post systemic transplantation, H2 generators-laden MSCs home to OA joints, and upon stimulation in acidic OA environment, H2 produced from the generators remodels articular redox balance, thereby relieving the loss of mitochondrial membrane potential, decreasing cell apoptosis rate, and maintaining pluripotent and paracrine functions of MSCs. Furthermore, the reactive oxygen species scavenging by H2 in combination with paracrine effects of the MSCs promote macrophage polarization towards the anti-inflammatory M2 phenotype, which contributes to reversing synovial immune disorder. In severe OA model, the backpacked MSCs reduce osteoarthritic degeneration, osteophyte formation and joint inflammation, and promote cartilage regeneration. In sum, our work demonstrates that arming with H2 generators effectively boosts the therapeutic efficacy of MSCs, which hold great potential for alleviating redox imbalance-related tissue lesions, including but not limited to OA.

A novel hypochlorous acid-activated NIR fluorescent probe with a large Stokes shift for bioimaging and early diagnosis of arthritis

In this work, we synthesized a novel hypochlorous acid-activated near-infrared (NIR) fluorescent probe (RhSBZ) by a strategy of enhancing π-conjugation through modification the 3,6-substituents of xanthene. Specifically designed for HClO bioimaging and arthritis diagnosis, RhSBZ displayed exceptional performance. RhSBZ exhibited a Stokes shift of 148 nm, high sensitivity, excellent selectivity, and a detection limit as low as 4.95 nM for HClO. Especially, upon reaction with HClO, the fluorescence intensity of RhSBZ enhanced dramatically by 61-fold. Notably, RhSBZ not only can detect exogenous and endogenous HClO in MCF-7 cells, but also has impressive imaging depth of up to 140 μm in rat liver tissues. More encouragingly, RhSBZ can be successfully used for the early diagnosis of abdominal inflammation and arthritis in mice. In summary, RhSBZ displayed excellent bioimaging capabilities and will have the potential application in the early diagnosis of inflammation diseases.

Colorimetric detection of cancer biomarker by using porous Mn-N-C single-atom nanozyme with peroxidase-like activity

Glutathione (GSH) is a critical antioxidant in biological systems involved in various cellular processes such as cell proliferation and apoptosis, and is considered as one of the cancer biomarkers. However, the conventional methods for detecting GSH levels often involve complex and time-consuming preparation and sophisticated equipment, posing challenges for rapid and straightforward analysis. Herein, we develop a colorimetric nanosensor using porous single-atom nanozymes (SAzymes), particularly those consisting of atomically dispersed metals on nitrogen-doped carbon supports (M-N-C), to monitor GSH quantitatively. The Mn-N-C SAzymes catalyze the oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) by hydrogen peroxide (H2O2), resulting in a measurable color change. The high porosity of the Mn-N-C SAzymes offers a large surface area accommodating a high density of accessible active sites for efficient catalysis. The addition of GSH in this system leads to a notable reduction in color intensity, offering an effective method for the quantitative measurement of GSH. The Mn-N-C SAzymes demonstrate high efficacy in the rapid colorimetric detection of GSH, with a low detection limit of 0.70 μM and a broad dynamic range of 0-40 μM. This method is further applied for a simple and rapid colorimetric analysis of the cancer biomarker in various biological samples, including tissues and serum. Demonstrating the potential for diagnostic applications, this approach offers a promising tool for clinical diagnostics, enabling reliable and convenient monitoring of GSH levels, which is crucial for assessing disease progression.

DNA aptamer targeting zinc transporters ZIP10 and ZIP6 on cancer cells

Cell-SELEX is an effective method for generating aptamers that specifically bind molecules in their native state on live cells. It not only uncovers novel potential biomarkers but also provides robust molecular recognition tools for a wide spectrum of applications. In this work, we generate a high affinity aptamer, HL15, through Cell-SELEX. A refined sequence HL15a demonstrated a strong binding affinity to target cells, with a minimal dissociation constant (Kd) of just 1.90 ± 0.49 nM. Subsequent truncation and mutation assays revealed that the core sequence of HL15a forms an antiparallel G-quadruplex structure. Furthermore, the target proteins of aptamer HL15a were identified and confirmed to be ZIP10 and ZIP6, both members of the zinc transporter ZIP family with high homology. Using HL15a as a molecular probe, we detected a range of universal binding affinities to the majority of tumor cells in the 48 cell lines evaluated. Furthermore, HL15a was effectively applied to distinguish high malignancy cancer tissues from both normal and low malignancy tissues in the pathological sections of breast and prostate cancers. Given that ZIP10 and ZIP6 play crucial roles in regulating zinc homeostasis and are implicated in numerous diseases, the aptamer HL15a offers a powerful tool for the study and potential therapeutic intervention of these two proteins.

Manganese-based virus-mimicking nanomedicine with triple immunomodulatory functions inhibits breast cancer brain metastasis

Hindered by the challenges of blood-brain barrier (BBB) hindrance, tumor heterogeneity and immunosuppressive microenvironment, patients with breast cancer brain metastasis have yet to benefit from current clinical treatments, experiencing instead a decline in quality of life due to radiochemotherapy. While virus-mimicking nanosystems (VMN) mimicking viral infection processes show promise in treating peripheral tumors, the inability to modulate the immunosuppressive microenvironment limits the efficacy against brain metastasis. Accordingly, a VMN-based triple immunomodulatory strategy is initially proposed, aiming to activate innate and adaptive immune responses and reverse the immunosuppressive microenvironment. Here, manganese-based virus-mimicking nanomedicine (Vir-HD@HM) with intratumoral drug enrichment is engineered. Vir-HD@HM can induce the immune response through the activation of cGAS-STING by mimicking the in vivo infection process of herpesviruses. Meanwhile, DNAzyme mimicking the genome can rescue the epigenetic silencing of PTEN with the assistance of Mn2+, thus ameliorating the immunosuppressive metastatic microenvironment and achieving synergistic sensitizing therapeutic efficacy. In vivo experiments substantiate the efficacy of Vir-HD@HM in recruiting NK cells and CD8+ T cells to metastatic foci, inhibiting Treg cells infiltration, and prolonging murine survival without adjunctive radiochemotherapy. This study demonstrates that Vir-HD@HM with triple immunomodulation offers an encouraging therapeutic option for patients with brain metastasis.

A protective growth factor delivery strategy based on polyphenol-protein self-assembly to promote inflammatory bone regeneration

The efficacy of growth factor delivery-based therapies for bone tissue regeneration is frequently undermined by oxidative stress, especially under inflammatory conditions, which results in structure damage and function inactivation of growth factors. Herein, a straightforward and universal protective delivery strategy is proposed by employing the multiple physical interactions between epigallocatechin-3-gallate (EGCG) and growth factors (e.g., neuregulin-1/NRG-1) to efficiently form self-assembled particles (NE APs). NE APs provide sustained release of NRG-1 while protecting it from oxidative damage, preserving its biological functions of cell recruitment, migration, and angiogenesis. Additionally, NE APs leverage EGCG's ability to scavenge reactive oxygen species and maintain mitochondrial homeostasis, while synergistically enhancing TNF/NF-κB/JAK-STAT signaling pathways to support immune responses and osteogenic differentiation. In vivo experiments demonstrated that NE APs create a favorable microenvironment for bone regeneration through stem cell recruitment, angiogenesis, and immune modulation, effectively promoting the repair of inflammatory bone defects. This versatile protective delivery strategy, based on polyphenol and growth factor self-assembly, offers the potential to advance the application of growth factors in regenerative medicine.

Engineering a cascaded isothermal signal amplification network using dimeric-palindromic primers for label-free detection of terminal deoxynucleotidyl transferase activity

Terminal deoxynucleotidyl transferase (TdT), a unique DNA polymerase essential for the human immune system, is highly active in leukemic cells, making it a key biomarker for leukemia. However, existing TdT detection methods are often complex, costly, and radioactive. This study presents a novel, label-free approach for detecting TdT activity using a cascaded isothermal signal amplification network with high efficiency. The method employs a single palindromic primer that self-dimerizes into a dimeric palindromic structure, subsequently extended by TdT to form poly-A chains. These chains undergo multisite polymerization and strand displacement, producing polymerization products converted into double-stranded DNA duplexes via palindrome-based reverse reading. Incorporating SYBR Green I dye, which binds specifically to double-stranded DNA, enables sensitive detection of TdT activity. This approach achieves high sensitivity and specificity, with a detection limit of 0.008 U/mL and a wide linear range of 0.008-50 U/mL. Practical applications were demonstrated with high recovery rates and low variability using mimic real biological samples, revealing the system's potential for biomedical use. The simplicity, robust signal amplification, and reliable assay performance of this method not only advance molecular diagnostic technologies but also offer a valuable new tool for TdT detection in both research and clinical settings.

A lipid droplet-targeted probe for imaging of lipid metabolism disorders during mitochondrial myopathy

Lipid metabolism is closely related to various biological processes in cells. The accumulation of Lipid droplets (LDs) is a typical manifestation of certain metabolic diseases, such as mitochondrial myopathy, which shows a significant increase in LDs. The accumulation of LDs can exacerbate the progression of disease, and lysosomes selectively degrade LDs to cope with this phenomenon. Visualizing lipid metabolism disorders and the interaction between LDs and other organelles is of great significance for the diagnosis and understanding of various physiological processes within cells in diseases. In this work, we synthesized two novel LD fluorescent probes and screened the best PDM, which exhibited stable fluorescence performance and strong photobleaching resistance in complex environments. The dynamics of intracellular LDs were tracked using PDM, and abnormal lipid metabolism within mitochondrial myopathy cells was visualized. This provides new tools and perspectives for studying LD dynamics and diagnosing mitochondrial myopathy.

Triple-signal strategy utilizing a colorimetric, fluorescence, and chromogenic paper-based sensor for rapid detection of ATP at neutral pH

This study presents a novel triple signal amplification strategy for paper-based colorimetric/fluorescence/chromogenic detection of adenosine triphosphate (ATP). Fluorescent gold nanoclusters (BSA-AuNCs) induce a redshift in the absorbance of quercetin (QCT), and the paper substrate displays a yellow color. Simultaneously, BSA-AuNCs activated QCT to emit fluorescence through the surface plasmon resonance (SPR) effect, producing a strong fluorescence signal at 541 nm, while the red fluorescence of BSA-AuNCs at 636 nm remained stable, resulting in a yellowish-green fluorescence of the paper. Upon the addition of ATP, the absorbance appeared to blue shift, and the paper substrate transitioned from yellow to colorless within 30 s. Concurrently, the fluorescence intensity of QCT decreased significantly, while the fluorescence intensity of BSA-AuNCs at 636 nm was almost unchanged, leading the fluorescence of the paper substrate to gradually shift to red. The QCT/BSA-AuNC paper-based system functions as a dual-signal sensor, enabling rapid ATP detection through both colorimetric and fluorescence modes with limits of detection (LOD) of 0.72 μM and 0.68 μM, respectively. Additionally, ATP enhances the peroxidase-like catalytic activity of BSA-AuNCs, promoting the chromogenic reaction of TMB and turning the paper sensor dark blue, with a LOD of 0.43 μM. This triple signal amplification method enables sensitive ATP screening using paper-based test strips, providing high sensitivity, selectivity, and reliable quantitative results. Notably, this three-mode sensing strategy holds significant potential for development into a quantitative method for ATP detection in normal and tumor cell samples, aiding in cell identification.

Characterization of atmospheric humic-like substances (HULIS) at a high elevation in North China: Abundance, molecular composition and optical properties

The optical absorption of large molecular compounds HULIS (humic-like substances) can significantly impact the aerosol light absorption and radiative forcing, influencing cloud condensation nuclei formation and thus the climate and atmospheric environment. This study collected aerosol (PM2.5) samples from the summit of Mount Tai in North China to investigate the concentration, molecular composition, and optical properties of HULIS. The average concentration of HULIS in the PM2.5 in this study was 1.26 ± 0.54 µg/m3, comprising for 56 % of the water-soluble organic carbon (WSOC), with levels lower than urban areas but higher than other mountainous regions. Mass spectrometry revealed that CHO and CHON components, with high aromaticity and phenolic groups, are major contributors to absorption and fluorescence. These results indicate that HULIS is mainly composed of lignin and proteins/amino sugars, derived from combustion and secondary formation, and possesses a high light absorption capacity (with MAE365 (mass absorption efficiency) and AAE (Ångström exponent) indices of 0.62 m2/g and 4.99, respectively). Parallel factor analysis identified three fluorescence components of HULIS, with proportions of 60.8 % for less oxygen humic-like substances, 21.0 % for high oxygen humic-like substances, and 18.2 % for protein-like substances. Our study highlights the significance of the light-absorbing capacity and secondary formation of HULIS at Mount Tai, laying the groundwork for investigation into the climate effects, formation mechanisms, and sources of HULIS generation.

One-stop solution for wide polar range compounds: Preparation and application of quaternary ammonium salt molecular cage stationary phase

The separation and analysis of complex samples with wide polar range on a singular column is always a difficult problem in separation and analysis science. In this study, the RCC3-R molecular cage modified with the quaternary ammonium salt stationary phase (RCC3-GQ@silica) was successfully prepared and applicated in the separation of wide polar range compounds. In the Reverse Phase Liquid Chromatography (RPLC) mode, due to the hydrophobicity and π-π interactions provided by the cyclohexane and benzene rings in the molecular cage structure, this stationary phase demonstrated effective separation capabilities for alkylbenzenes, polycyclic aromatic hydrocarbons, phenols, and anilines. In the Hydrophilic Interaction Liquid Chromatography (HILIC) mode, the study explored the separation performance of this stationary phase for sugars and inorganic salts. Utilizing a mixed mode of HILIC/RPLC/Ion Exchange Chromatography (IEC), effective separation was achieved for sulfonamides, nucleosides, acids, and amino acids, indicating good separation effects for medium to strongly polar compounds as well as various hydrophilic compounds. Combining various separation modes, the RCC3-GQ@silica stationary phase successfully separated 91 compounds across 15 categories. These results not only demonstrate the potential of the stationary phase in expanding the range of polarities of analyzable compounds and achieving multipurpose use on a single column, but also confirm its effective separation of nucleosides in pure water systems, further emphasizing the significant application potential of RCC3-GQ@silica stationary phase in the field of green chemistry.

Biogenic amines detection in food: Emerging trends in electrochemical sensors

Amines are ubiquitous in living organisms and play essential roles in various physiological functions, including neurotransmission, hormonal regulation, cell signalling, and metabolism. In daily life, amines are found in cosmetics, pharmaceuticals, and foods. However, biogenic amines, formed through amino acid decarboxylation during food degradation, present a significant health risk, especially when combined with nitrites and nitrates in foods. Therefore, stringent control measures are essential. Thus, the development of user-friendly sensor devices for on-site monitoring of these molecules is a crucial area of research, because limited portable and simple options for amine detection and quantification are currently available. Electrochemical sensors offer an attractive solution for reliable and sensitive on-site measurements. With these sensors it is possible to carry out measurements, without complex sample processing. This review provides an overview of advancements in electrochemical sensors for detecting and quantifying various amines, highlighting the potential of different sensor configurations, sensing elements, and underlying detection mechanisms.

Aggregation-induced emission-based aptasensors for the detection of various targets: Recent progress

The advancement of aptasensors utilizing aggregation-induced emission (AIE) has progressed remarkably in recent years, owing to various unique benefits provided by aggregation-induced emission luminogens (AIEgens) as a novel category of fluorescent substances and aptamers as exceptional recognition components. AIE refers to a photophysical phenomenon identified in certain luminogens that show minimal or absent emission in dilute solutions, yet display considerable emission when in aggregate or solid states. Fluorescent sensing is an effective technique for the detection of various targets; however, many traditional dyes frequently demonstrate an aggregation-caused quenching (ACQ) effect in solid form, which limits their applicability on a larger scale. In contrast, fluorescent probes that leverage AIE characteristics have garnered considerable interest, owing to their elevated fluorescence quantum yields and ease of fabrication. This review discusses the application of various AIEgens in the design of diverse sensitive and selective AIE-based aptasensors for monitoring various targets, with a particular focus on recent advances. The AIE-based aptasensors exploit the supreme affinity of the aptamers to their targets and the remarkable properties of AIEgen, including its photostability and high quantum yield, and the interaction between AIEgen and DNA. The objective is to acquaint researchers with the various categories of materials exhibiting AIE characteristics and their potential applications in the creation of different aptasensors, enabling them to introduce novel kinds of innovative AIEgens and AIE-integrated aptasensors.

Morphological advances and innovations in conjugated polymer films for high-performance gas sensors

Conjugated polymers (CPs) are considered one of the most important gas-sensing materials due to their unique features, combining the benefits of both metals and semiconductors, along with their outstanding mechanical properties and excellent processability. However, CPs with conventional morphological structures, such as largely amorphous and bulky matrices, face limitations in practical applications because of their inferior charge transport characteristics, low surface area, and insufficient sensitivity. Therefore, the design and development of novel morphological nanostructures in CPs have attracted significant attention as a promising strategy for improving morphological and electrical characteristics, thereby enabling a considerable increase in the sensing performance of corresponding gas sensors. Numerous CP nanostructures have been developed and implemented for high-performance gas sensors. Highlighting the morphological advances and bottlenecks of these nanostructures is crucial for providing an overview of developing trends, potential strategies, and emerging areas for the future development of CP nanostructures in the field. In this regard, this study describes state-of-the-art CP nanostructures, emphasizing their attractive morphological and electrical characteristics to help readers and researchers better understand emerging trends, promising future directions, and key obstacles for the application of CP nanostructure-based gas sensors. The most crucial aspects of CP nanostructures, including advanced preparation techniques, morphological properties, and sensing characteristics, are discussed and assessed in detail. Moreover, development strategies and perspectives for achieving high sensing efficiency in CP nanostructure-based flexible and wearable sensors are summarized and emphasized.

First truly deep eutectic solvent (DES) based stationary phase for high-performance liquid chromatography (HPLC)

Deep eutectic solvents (DESs) have gained significant attention due to their environmentally friendly properties and versatile applications in various fields, including analytical chemistry. This study investigates the use of a deep eutectic solvent (DES) composed of l-proline protonated with hydrochloric acid and xylitol as a surface modifier for silica-based stationary phases in high-performance liquid chromatography (HPLC). The DES was successfully immobilized on silica, and its impact on chromatographic performance was evaluated in normal-phase liquid chromatography (NP-HPLC). It was observed that DES immobilized layer acted as a real liquid stationary phase. The DES-modified columns exhibited improved selectivity, resolution for polar analytes, and shorter retention times for non-polar compounds compared to unmodified silica columns. Additionally, the DES-modified phase demonstrated long-term stability over multiple chromatographic cycles. These results highlight the potential of DESs as customizable, environmentally friendly stationary phase modifiers for enhancing chromatographic efficiency and selectivity, particularly in separating polar analytes, opening new avenues for the development of advanced chromatographic materials and contributing to greener and more efficient separation techniques. The robust preparation method also facilitates easy scalability for large-scale applications, such as the isolation of valuable compounds and the purification of complex mixtures, including phenols, amines, and nitro-derivatives.

Cu@ZIF-8 coupled to UPLC-UV for rapid and sensitive analysis of emodin and rhein in urine samples

This study presented the development of a novel adsorbent system through the synthesis of cationic surfactant-modified Cu-doped ZIF-8 (Cu@ZIF-8), leveraging the synergistic advantages of bimetallic-enhanced surface area and surfactant-mediated stability. Among various surfactants evaluated, dodecyltrimethylammonium bromide (DTAB)-functionalized Cu@ZIF-8 exhibited superior adsorption performance toward emodin and rhein, driven by combined π-π interactions and hydrogen bonding. This optimized adsorbent facilitated the development of an innovative analytical method integrating Cu@ZIF-8-based extraction with UPLC-UV for the trace-level quantification of target analytes in complex biological matrices. Comprehensive optimization of critical extraction and desorption parameters yielded a robust analytical protocol with excellent linearity (0.05-5.00 μg/mL; R² = 0.9993 and 0.9980), sensitive detection limits (0.01 μg/mL), and satisfactory recovery (92.73-108.86 %). The validated method successfully characterized the urinary pharmacokinetic profiles of emodin and rhein following rhubarb extract administration in rats. Compared to conventional protein precipitation approaches, this approach offers significant advantages in simplicity, analysis speed and environmental compatibility. These findings position surfactant-engineered Cu@ZIF-8 as a promising platform for bioanalytical applications, particularly in the quantification of anthraquinone derivatives in biological specimens.

Vacancies-rich Z-scheme VdW heterojunction as H2S-sensitized synergistic therapeutic nanoplatform against refractory biofilm infections

Encapsulated in a self-produced negatively charged extracellular polymeric substance (EPS) matrix, the wound infected bacterial biofilms exhibit formidable resistance to conventional positively charged antibiotics and host's immune responses, which can undoubtedly lead to persistent infections and lethal complications. Nevertheless, developing efficacious strategies to root out stubborn biofilm and promote tissue regeneration still remains a challenge. To resolve this dilemma, a versatile vacancies-rich Z-scheme MoSSe Van der Waals heterojunction (MoSSe VdW HJ) is rationally fabricated as nanoplatform for hydrogen sulfide (H2S)-sensitized synergistic therapy of wound bacterial biofilm infection. The rich anion vacancies and Z-scheme heterostructure make the fabricated MoSSe VdW HJ can effectively augment H2S, localized hyperthermia, and reactive oxygen species production under the stimulation of biofilm microenvironments (BME) and irradiation of 808 nm near-infrared (NIR) light. Therefore, MoSSe VdW HJ is capable to integrate H2S gas, chemodynamic, photothermal, and photodynamic therapies to effectively destroy eDNA and polysaccharides in the EPS matrix, thereby breaching the biofilm barrier to eradicate bacteria and facilitate wound healing. The synergistic strategy exhibits superior anti-biofilm and wound repair effects both in vivo and in vitro, thus providing guideline for the development of BME and NIR light activated synergistic therapeutics to fight against refractory biofilm infections.

Target-induced reconstruction of Ru(bpy)32+-loaded gold nanocage for one-step highly sensitive detection of Hg2

In this work, Ru(bpy)32+-loaded gold nanocage (AuNCs) (Ru-AuNCs) was prepared and found to display a distinct property of electrochemiluminescence (ECL) enhancement under mercury ions (Hg2+) interaction. Based on this, we designed a screen-printed bipolar electrode-ECL (SPBPE-ECL) sensing platform by coupling with the thymine-Hg2+-thymine (T-Hg2+-T) binding pattern for one-step highly sensitive detection of Hg2+. This ECL sensor showed a wide linear detection range (0.75 - 850 μg L-1) and low detection limit (0.1290 μg L-1) toward Hg2+, with a one-step detection procedure and disposable feature, displaying potential applicability in the point-of-care-testing (POCT) of Hg2+ in the environment. In addition, the Hg2+-mediated ECL signal enhancement mechanism of Ru-AuNCs was also investigated. It was confirmed that Hg2+ interaction etched the cage structure of Ru-AuNCs, which sped up the release of more Ru(bpy)32+ around the sensing electrode. Furthermore, Au-Hg alloy structure was formed on the surface of Ru-AuNCs, which also improved the ECL signal. This target-induced in-situ sensing material surface reconstruction strategy would provide a better design concept for the construction of ECL POCT sensor.

Isotope-coded hydrazide tags for MALDI-MS based quantitative glycomics

The detection of glycosylation alterations is essential for elucidating the roles of glycan functions in biological processes and identifying potential disease biomarkers. Stable isotopic chemical labeling, coupled with mass spectrometry (MS), represents a powerful approach in quantitative glycomics. In this study, we synthesized a novel isotopic hydrazide pair, 2,6-Dimethyl-4-chinolincarbohydrazid (DMQCH) and its deuterium isomer DMQCH-d4, via an efficient and cost-effective method, and applied it for the first time in MALDI-MS-based quantitative glycomics. The hydrazide tags, DMQCH/DMQCH-d4, enabled stable mass shifts through reductive-terminal reactions with glycans, allowing for differential mass tagging of two samples without additional purification after derivatization. This DMQCH/DMQCH-d4 pair exhibited high derivatization efficiency (including on-target derivatization), substantial improvements in MS signal intensity (a 15-fold increase for maltoheptaose, high reproducibility (CV < 13.6 %), and excellent linearity (R2 > 0.99) over two orders of magnitude in dynamic range for the relative quantitative analysis of maltoheptaose. Furthermore, this isotopic hydrazide pair was validated by successfully measuring changes in serum N-glycan profiles from individuals with healthy human serum control and ovarian cancer, highlighting its potential in quantitative glycomics for clinical applications.

Three-dimensional urchin-like K2Ti8O17 / Ag NPs composite as a SERS substrate for detecting folic acid and thiram

The three-dimensional (3D) semiconductor/noble metal composite substrates for surface-enhanced Raman scattering (SERS) have garnered increasing interest due to their excellent optical and chemical properties, as well as the capacity to trigger both electromagnetic mechanism (EM) and chemical mechanism (CM) simultaneously. In this work, a facile 3D urchin-like K2Ti8O17/Ag nanoparticles (Ag NPs) composite substrate is designed for multi-purpose SERS sensing. K2Ti8O17, as a dielectric medium, improves the electric field environment around Ag NPs, which is consistent with finite-different time domain (FDTD) results, and enhances the SERS performance of the K2Ti8O17/Ag composite substrate. Besides, the efficient "donor-bridge-acceptor" charge transfer mode, explored through energy level calculations and enhanced utilization of incident light, further strengthens the SERS performance. Results show that the prepared K2Ti8O17/Ag NPs substrate exhibits high detection sensitivity, with 10-11 and 10-12 M limits in detecting Methylene Blue (MB) and Crystal Violet (CV), and the enhancement factors (EFs) of 2.66 × 109 and 6.07 × 109, respectively. At the same time, the composite substrate also possesses good signal uniformity (RSD = 10.5 %) and promising photocatalytic ability. For practical applications, the prepared K2Ti8O17/Ag NPs substrate can detect folic acid of 10-7 M in the diluted serum environment and thiram of 10-8 M in lake water, respectively. The urchin-like K2Ti8O17/Ag NPs substrate expands the range of 3D semiconductor composite SERS substrates, which is expected to be used for biosensing and trace analysis of harmful substances.

A perspective on the potential use of aptamer-based field-effect transistor sensors as biosensors for ovarian cancer biomarkers CA125 and HE4

Ovarian cancer (OC) is one of the most fatal gynaecological malignancies, primarily because of its typically asymptomatic early stages, which complicates early detection. Therefore, developing sensitive and appropriate biomarkers for efficient diagnosis of OC is urgently needed. Aptamers, short sequences of single-stranded DNA or RNA molecules, have become crucial in tumor diagnosis because of their high affinity for specific molecules produced by tumors. This ability allows aptamers to accurately detect OC, thus providing better survival rates and a reduced disease burden. Biosensors that combine recognition molecules and nanomaterials are essential in various fields, including disease diagnosis and health management. Molecular-specific field-effect transistor (FET) biosensors are particularly promising due to their rapid response times, ease of miniaturization, and high sensitivity in detecting OC. Aptamers, which are known for their stability and structural tunability, are increasingly being used as biological recognition units in FET biosensors, offering selective and high-affinity binding to target molecules that are ideal for medical diagnostics. This review explores the recent advancements in biosensors for OC detection, including FET biosensors with aptamer-functionalized nanomaterials for CA125 and HE4. Furthermore, this review provides an overview of the structure and sensing principles of these advanced biosensors, preparation methods and functionalization strategies that enhance their performance. Additionally, notable progress and potential of biosensors, including aptamer-functionalized FET biosensors for OC diagnosis have been summarized, emphasising their role and clinical validation in advancing medical diagnostics and improving patient outcomes through enhanced detection capabilities.

Force-electric biomaterials and devices for regenerative medicine

There is a growing recognition that force-electric conversion biomaterials and devices can convert mechanical energy into electrical energy without an external power source, thus potentially revolutionizing the use of electrical stimulation in the biomedical field. Based on this, this review explores the application of force-electric biomaterials and devices in the field of regenerative medicine. The article focuses on piezoelectric biomaterials, piezoelectric devices and triboelectric devices, detailing their categorization, mechanisms of electrical generation and methods of improving electrical output performance. Subsequently, different sources of driving force for electroactive biomaterials and devices are explored. Finally, the biological applications of force-electric biomaterials and devices in regenerative medicine are presented, including tissue regeneration, functional modulation of organisms, and electrical stimulation therapy. The aim of this review is to emphasize the role of electrical stimulation generated by force-electric conversion biomaterials and devices on the regulation of bioactive molecules, ion channels and information transfer in living systems, and thus affects the metabolic processes of organisms. In the future, physiological modulation of electrical stimulation based on force-electric conversion is expected to bring important scientific advances in the field of regenerative medicine.

Reprogrammed glycolysis-induced augmentation of NIR-II excited photodynamic/photothermal therapy

Small molecule-based multifunctional optical diagnostic materials have garnered considerable interest due to their highly customizable structures, tunable excited-state properties, and remarkable biocompatibility. We herein report the synthesis of a multifaceted photosensitizer, PPQ-CTPA, which exhibits exceptional efficacy in generating Type I reactive oxygen species (ROS) and thermal energy under near-infrared-II (NIR-II, >1000 nm) laser excitation at 1064 nm, thereby combining photodynamic therapy (PDT) and photothermal therapy (PTT) functionalities. To enhance therapeutic efficacy, we engineered lonidamine (LND) by conjugating it with triphenylphosphonium (TPP) cations, producing LND-TPP. This compound inhibits mitochondrial glycolysis and downregulates heat shock protein 90 (HSP 90) levels in a breast cancer mouse model, potentiating both PDT and PTT. For in vivo applications, PPQ-CTPA and LND-TPP are encapsulated within the amphiphilic polymer DSPE-SS-PEG to obtain PPQ-CTPAL NPs. In breast cancer cell lines, PPQ-CTPAL NPs are decomposed by cellular GSH, simultaneously releasing the dual-functioning photosensitizer PPQ-CTPL and the mitochondria-disrupting agent LND-TPP. Upon 1064 nm laser irradiation, we found that tumor growth in breast cancer mice is effectively restrained by PPQ-CTPAL NPs. This work highlights the synergistic integration of PDT, PTT, and chemotherapy facilitated by NIR-II fluorescence, photoacoustic, and photothermal imaging under 1064 nm irradiation, underscoring the clinical potential of multifunctional phototherapeutic agents.

Distinct impacts of aging on the immune responses to extracellular matrix-based versus synthetic biomaterials

All implanted materials inevitably trigger an acute inflammatory response. The long-term outcome, however, is dependent on the trajectory of this response. This study investigates the effects of aging on the immune response to two commercially available biomaterials. Extracellular matrix-based urinary bladder matrix (UBM) and synthetic polypropylene mesh (PPM) were implanted in young (4 months) and aged (18 months) C57BL/6J mice. Overall, PPM led to a sustained inflammatory response regardless of the age of the mice. In contrast, UBM induced an initial inflammatory response that matured into a pro-regenerative/remodeling response with time, though aged mice exhibited a delayed resolution of inflammation. The PPM-induced response was predominantly pro-inflammatory with consistently higher M1-like macrophage phenotype, whereas the response to UBM was characterized by an anti-inflammatory M2-like phenotype, especially in young mice. RNA sequencing revealed marked age-related differences in gene transcription. At day 7 post-implantation, the young mice with UBM showed a robust upregulation of both pro- and anti-inflammatory pathways as compared to young mice implanted with PPM, however, by day 14, the gene expression profile transitioned into an anti-inflammatory profile. Intriguingly, in aged mice, the response to UBM was distinct with consistent downregulation of inflammatory genes compared to PPM, while the response to PPM in both young and aged animals was largely consistent. Upstream analysis identified cytokines as key drivers of the host response, with IL-4 and IL-13 in young mice, and TNF-α and IL-1β driving chronic inflammation in aged mice. These findings highlight the importance of host age in biomaterial outcome, and the potential of ECM-based materials to mount a favorable response even in the presence of age-related immune dysregulation.

Mussel-inspired surface-engineering of 3D printed scaffolds employing bedecked transition metal for accelerated bone tissue regeneration

In modern civilization with fast work culture and uncontrolled lifestyles increase bone-related problems, moreover, lack of auto-regeneration of bone, indulge to formulate a suitable methodology to get rid of this problem. In this article, nanohydroxyapatite (nHA) decorated hierarchical titanium phosphate (TP) was synthesized by solvothermal process and incorporated into newly synthesized tartaric acid-based polyurethane (PU) through in situ technique. The porous 3D scaffold was fabricated by most advanced 3D printing technique with desired porous structure in a controlled manner. The biochemical properties of scaffold's surface were improved via immobilizing polydopamine (PDA) at ambient temperature. Elemental analysis indicated that TP-doped nanohybrid scaffolds experienced higher amount of PDA immobilization as compared to pristine and nHA-doped scaffolds. The unoccupied 'd' orbital of introduced Ti can form a coordinate bond with catechol groups of dopamine (DA) which augments PDA deposition on the scaffold's surface. Furthermore, the higher effective nuclear charge (Z⁎) of tetravalent Ti ion generates an effective dative bond with the urethane groups of PU chain which improves hardness and tensile strength (TS) of produced nanocomposites (PU/TP-nHA) remarkably by 71.3 % and 126 % compared to pristine PU. Ti-doped nanohybrid scaffolds, containing calcium and phosphate components with higher amounts of deposited PDA exhibited improved in vitro osteogenic bioactivity. Moreover, in vivo study expressed superior bone regeneration efficacy of the TP-doped nHA-integrated PU scaffold without showing any organ toxicity. Thus, the optimum level of TP-doped nHA with higher amount of PDA-immobilized PU nanohybrid scaffold would be a suitable bone graft substitute in bone regeneration applications.

Bioactive polymers as stimulus-responsive anti-metastatic combination agents to treat pancreatic cancer

The intractable and devastating nature of pancreatic ductal adenocarcinoma (PDAC) necessitates an urgent need for novel therapies. This study presents the development of a novel polymer prodrug system for the combination treatment of PDAC, based on an optimized pharmacologically active anti-metastatic macromolecular carrier, PCQ, conjugated with gemcitabine (GEM). Structure-activity relationship evaluations showed that random PCQ copolymers exhibited superior anti-migratory activity compared to the gradient PCQ analogs. GEM was incorporated into the random PCQ copolymers using disulfide linker to prepare a reduction-responsive prodrug, PCQ(r)6-SS-GEM12. The resultant therapeutic system presents a pharmacologically active delivery strategy that targets both the proliferative and the metastatic phenotype in PDAC. The PCQ(r)6-SS-GEM12 prodrug demonstrated a selective release of GEM under the reductive tumor environment leading to a significant inhibition of tumor growth with pronounced anti-metastatic effect. Collectively, our data show that the combination of anti-metastatic PCQ and cytotoxic GEM-based reduction-responsive prodrug polymer offers an innovative strategy to treat PDAC.

Simultaneous measurement of multiple fluorine labelling effect on GB1 stability by 19F NMR

The incorporation of fluorinated amino acids into proteins through natural biosynthesis in E. coli often leads to the production of heterogeneous fluorinated proteins. The stabilities of proteins with different 19F labelling states can vary, but these differences are challenging to measure due to the difficulty in separating the fluorinated protein mixtures that differ by only a few 19F atoms. Here, we simultaneously incorporated both fluoro-phenylalanines (3-fluoro-phenylalanine, 3FF; or 4-fluoro-phenylalanine, 4FF) and 5-fluoro-tryptophan (5FW) into GB1 protein. We are able to measure the stability of GB1 protein with different 19F labelling states without the need for sample separation by taking the advantage of 19F NMR. The results showed that 4FF-5FW-GB1 with varying 19F labelling states exhibited significantly different protein stability, with higher 4FF labeling efficiency correlating with decreased stability. Furthermore, residues F30 and F52 show synergistic effects on GB1 stability. In contrast, the 3FF and 5FW substitution exhibits a slightly stabilizing effect on GB1 stability. The present research provides a convenient 19F NMR method to simultaneously measure fluorine labelling effects on protein stability, favouring precise understanding and analysis of fluorine labelling effects.

Multifunctional nanozymatic biosensors: Awareness, regulation and pathogenic bacteria detection

It is estimated that approximately 700,000 fatalities occur annually due to infections attributed to various pathogens, which are capable of dissemination via multiple environmental vectors, including air, water, and soil. Consequently, there is an urgent need to enhance and refine rapid detection technologies for pathogens to prevent and control the spread of associated diseases. This review focuses on applying nanozymes in constructing biosensors, particularly their advancement in detecting pathogenic bacteria. Nanozymes, which are nanomaterials exhibiting enzyme-like activity, combine unique magnetic, optical, and electronic properties with structural diversity. This blend of characteristics makes them highly appealing for use in biocatalytic applications. Moreover, their nanoscale dimensions facilitate effective contact with pathogenic bacteria, leading to efficient detection and antibacterial effects. This article briefly summarizes the development, classification, and strategies for regulating the catalytic activity of nanozymes. It primarily focuses on recent advancements in constructing biosensors that utilize nanozymes as probes for sensitively detecting pathogenic bacteria. The discussion covers the development of various optical and electrochemical biosensors, including colorimetric, fluorescence, surface-enhanced Raman scattering (SERS), and electrochemical methods. These approaches provide a reliable solution for the sensitive detection of pathogenic bacteria. Finally, the challenges and future development directions of nanozymes in pathogen detection are discussed.

Advancements in membrane technology for efficient POME treatment: A comprehensive review and future perspectives

The treatment of POME related contamination is complicated due to its high organic contents and complex composition. Membrane technology is a prominent method for removing POME contaminants on account of its efficiency in removing suspended particles, organic substances, and contaminants from wastewater, leading to the production of high-quality treated effluent. It is crucial to achieve efficient POME treatment with minimum fouling through membrane advancement to ensure the sustainability for large-scale applications. This article comprehensively analyses the latest advancements in membrane technology for the treatment of POME. A wide range of membrane types including forward osmosis, microfiltration, ultrafiltration, nanofiltration, reverse osmosis, membrane bioreactor, photocatalytic membrane reactor, and their combinations is discussed in terms of the innovative design, treatment efficiencies and antifouling properties. The strategies for antifouling membranes such as self-healing and self-cleaning membranes are discussed. In addition to discussing the obstacles that impede the broad implementation of novel membrane technologies in POME treatment, the article concludes by delineating potential avenues for future research and policy considerations. The understanding and insights are expected to enhance the application of membrane-based methods in order to treat POME more efficiently; this will be instrumental in the reduction of environmental pollution.

Energy metabolism disturbance induced by atorvastatin exposure on yellowstripe goby (Mugilogobius chulae) larvae based on transcriptome and metabolome analysis

Atorvastatin (ATV), a commonly prescribed lipid-lowering drug, has been widely detected in various aquatic environments due to its large use and low degradation rate. Since the target gene inhibited by ATV is highly conserved in organisms, many studies have shown that ATV can interfere with lipid metabolism in aquatic non-target organisms. However, studies on mitochondria, energy metabolism, and developmental toxicity of ATV on non-target organisms are limited. In this study, Mugilogobius chulae embryos were exposed to ATV (0.5 and 50 µg/L) until 96 hour post fertilization (hpf). The results confirmed that the environmental concentrations of ATV caused toxic effects including developmental malformations, pathological damage, hepatotoxicity, and oxidative stress in M. chulae larvae. Both transcriptomic and metabolomic analyses showed that ATV exposure interfered the normal processes of oxidative phosphorylation and TCA cycle, resulting in energy metabolic disorder. In addition, ATV exposure also damaged the mitochondrial structure of M. chulae larvae. Thus, M. chulae could regulate PI3K/AMPK/FoxO proteins to promote mitochondrial regeneration, support autophagy, and even initiate apoptosis to maintain metabolism homeostasis. Taken together, our findings suggested that mitochondrial dysfunction and metabolic disorder were involved in ATV-induced toxicity which may cause developmental malformations and abnormalities, providing novel insight into the toxic mechanisms of ATV.

Catalytic oxidation of volatile organic compounds over supported noble metal and single atom catalysts: A review

Volatile organic compounds (VOCs) exhausted from industrial processes are the major atmospheric pollutants, which could destroy the ecological environment and make hazards to human health seriously. Catalytic oxidation is regarded as the most competitive strategy for the efficient elimination of low-concentration VOCs. Supported noble metal catalysts are preferred catalysts due to their excellent low-temperature catalytic activity. To further lower the cost of catalysts, single atom catalysts (SAC) have been fabricated and extensively studied for application in VOCs oxidation due to their 100 % atom-utilization efficiency and unique catalytic performance. In this review, we comprehensively summarize the recent advances in supported noble metal (e.g., Pt, Pd, Au, and Ag) catalysts and SAC for VOCs oxidation since 2015. Firstly, this paper focuses on some important influencing factors that affect the activity of supported noble metal catalysts, including particle size, valence state and dispersion of noble metals, properties of the support, metal oxide/ion modification, preparation method, and pretreatment conditions of catalysts. Secondly, we briefly summarize the catalytic performance of SAC for typical VOCs. Finally, we conclude the key influencing factors and provide the prospects and challenges of VOCs oxidation.

pH effects on graphene foam capacitance induced by adsorption of 1-pyrenemethylamine

The interfacial capacitance of graphene foam electrodes (Gii-Sens) in contact to aqueous media (determined by electrochemical impedance spectroscopy) is strongly affected by adsorption of 1-pyrenemethylamine (PMA). An order of magnitude increase in capacitance upon adsorption is ascribed predominantly to the quantum capacitance contribution (i.e. changes in the electronic density of states in graphene layers) in response to the cationic adsorbent. A change in capacitance (reversible) is observed as a function of pH. Although likely to be linked to the amine protonation, the change in measured capacitance occurs over a wide range of pH values (approx. linear from pH 2 to pH 12) and could provide a diagnostic capacitance-based tool for pH. Exploratory measurements in pure human serum (with pH adjustment) suggest that the capacitance effect is specific to protons and correlated to pH even in complex sensing media. However, the response of the graphene foam electrode surface is sensitive to the preparation and storage conditions and currently not fully understood.

Monitoring variations in mitochondrial hydrogen sulfide using two-photon cyclometalated iridium(III) complex probe: A new strategy for ischemia-reperfusion drug discovery and efficacy evaluation

Hepatic ischemia-reperfusion injury (HIRI) is one of the main causes of liver insufficiency and failure after liver surgery. However, the effectiveness of current methods of treating HIRI is generally limited. Previous studies have shown that hydrogen sulfide (H2S) has a beneficial effect on HIRI, and an appropriate concentration of H2S can significantly reduce HIRI by protecting the mitochondria. Therefore, establishing an accurate imaging platform for monitoring variations in mitochondrial H2S is an effective strategy for anti-HIRI drug discovery and efficacy evaluation. To this end, a cyclometalated iridium(III) complex-based probe, Cym-Ir-EDB, was developed for detecting mitochondrial H2S in HIRI. Cym-Ir-EDB possesses good sensitivity, high selectivity, negligible cytotoxicity, and excellent mitochondrial-targeting ability, rendering it a promising imaging tool for analyzing variations in mitochondrial H2S in HIRI cells. Using Cym-Ir-EDB as a probe, anti-HIRI drugs were screened from isothiocyanates by monitoring variations in mitochondrial H2S in HIRI cells, for the first time. Moreover, the dynamics of mitochondrial H2S in HIRI cells were visualized and the response of HIRI to treatment with the screened erucin was monitored. The findings indicate that Cym-Ir-EDB can serve as a useful imaging platform for the precise imaging of mitochondrial H2S in HIRI, thereby contributing to anti-HIRI drug discovery and efficacy evaluation.