TET-mediated 5hmC in breast cancer: mechanism and clinical potential

Breast cancer is the most common cancer among women, with differences in clinical features due to its distinct molecular subtypes. Current studies have demonstrated that epigenetic modifications play a crucial role in regulating the progression of breast cancer. Among these mechanisms, DNA demethylation and its reverse process have been studied extensively for their roles in activating or silencing cancer related gene expression. Specifically, Ten-Eleven Translocation (TET) enzymes are involved in the conversion process from 5-methylcytosine (5mC) to 5-hydroxymethylcytosine (5hmC), which results in a significant difference in the global level of 5hmC in breast cancer compared with normal tissues. In this review, we summarize the functions of TET proteins and the regulated 5hmC levels in the pathogenesis of breast cancer. Discussions on the clinical values of 5hmC in early diagnosis and the prediction of prognosis are also mentioned.

Development and application of an uncapped mRNA platform

BACKGROUND

A novel uncapped mRNA platform was developed.

METHODS

Five lipid nanoparticle (LNP)-encapsulated mRNA constructs were made to evaluate several aspects of our platform, including transfection efficiency and durability in vitro and in vivo and the activation of humoral and cellular immunity in several animal models. The constructs were eGFP-mRNA-LNP (for enhanced green fluorescence mRNA), Fluc-mRNA-LNP (for firefly luciferase mRNA), SδT-mRNA-LNP (for Delta strain SARS-CoV-2 spike protein trimer mRNA), gDED-mRNA-LNP (for truncated glycoprotein D mRNA coding ectodomain from herpes simplex virus type 2 (HSV2)) and gDFR-mRNA-LNP (for truncated HSV2 glycoprotein D mRNA coding amino acids 1-400).

RESULTS

Quantifiable target protein expression was achieved in vitro and in vivo with eGFP- and Fluc-mRNA-LNP. SδT-mRNA-LNP, gDED-mRNA-LNP and gDFR-mRNA-LNP induced both humoral and cellular immune responses comparable to those obtained by previously reported capped mRNA-LNP constructs. Notably, SδT-mRNA-LNP elicited neutralizing antibodies in hamsters against the Omicron and Delta strains. Additionally, gDED-mRNA-LNP and gDFR-mRNA-LNP induced potent neutralizing antibodies in rabbits and mice. The mRNA constructs with uridine triphosphate (UTP) outperformed those with N1-methylpseudouridine triphosphate (N1mψTP) in the induction of antibodies via SδT-mRNA-LNP.

CONCLUSIONS

Our uncapped, process-simplified and economical mRNA platform may have broad utility in vaccines and protein replacement drugs.KEY MESSAGESThe mRNA platform described in our paper uses internal ribosome entry site (IRES) (Rapid, Amplified, Capless and Economical, RACE; Register as BH-RACE platform) instead of caps and uridine triphosphate (UTP) instead of N1-methylpseudouridine triphosphate (N1mψTP) to synthesize mRNA.Through the self-developed packaging instrument and lipid nanoparticle (LNP) delivery system, mRNA can be expressed in cells more efficiently, quickly and economically.Particularly exciting is that potent neutralizing antibodies against Delta and Omicron real viruses were induced with the new coronavirus S protein mRNA vaccine from the BH-RACE platform.

Exploring RNA modifications in infectious non-coding circular RNAs

Viroids, small circular non-coding RNAs, act as infectious pathogens in higher plants, demonstrating high stability despite consisting solely of naked RNA. Their dependence of replication on host machinery poses the question of whether RNA modifications play a role in viroid biology. Here, we explore RNA modifications in the avocado sunblotch viroid (ASBVd) and the citrus exocortis viroid (CEVd), representative members of viroids replicating in chloroplasts and the nucleus, respectively, using LC - MS and Oxford Nanopore Technology (ONT) direct RNA sequencing. Although no modification was detected in ASBVd, CEVd contained approximately one m6A per RNA molecule. ONT sequencing predicted three m6A positions. Employing orthogonal SELECT method, we confirmed m6A in two positions A353 and A360, which are highly conserved among CEVd variants. These positions are located in the left terminal region of the CEVd rod-like structure where likely RNA Pol II and and TFIIIA-7ZF bind, thus suggesting potential biological role of methylation in viroid replication.

Exogenously applied ABA alleviates dysplasia of maize (Zea mays L.) ear under drought stress by altering photosynthesis and sucrose transport

Drought stress inhibits the development of maize ears. Abscisic acid (ABA) is a plant hormone that can regulate the physicology metabolism under abiotic stress. In this study, maize varieties Zhengdan 958 (ZD958) and Xianyu 335 (XY335) with different filling stages were used as materials. Three treatments were set in the filling period: normal irrigation (CK), drought stress (stress); exogenous ABA + drought stress (ABA+stress). They were used to study the physiological regulation of exogenous ABA on maize ears development during drought stress. Exogenous ABA inhibited bald tip and the decline of maize plant biomass, and increased the number and weight of grains per ear at harvest under drought stress by regulating photosynthetic pigment content (Chla, Chlb, Car), gas exchange parameters (Pn, Tr, gs, Ci, Ls), Chla fluorescence parameters (Fv/Fm, ФPSII, ETR, qP, NPQ), chloroplast structure and function, photosynthetic enzyme activity, and the transcription level of genes coding SUTs (ZmSUT1, ZmSUT2, ZmSUT4, ZmSUT6). There was a significant correlation between physiological indexes of sucrose loading in maize and yield factors. This study discussed the mechanism of exogenous ABA alleviating maize ear dysplasia at grain filling stage under drought stress from the perspective of photosynthesis and sucrose transport.

Urease in acetogenic Lachnospiraceae drives urea carbon salvage in SCFA pools

The gut microbiota produces short-chain fatty acids (SCFA) and acidifies the proximal colon which inhibits enteric pathogens. However, for many microbiota constituents, how they themselves resist these stresses is unknown. The anaerobic Lachnospiraceae family, which includes the acetogenic genus Blautia, produce SCFA, are genomically diverse, and vary in their capacity to acidify culture media. Here, we investigated how Lachnospiraceae tolerate pH stress and found that subunits of urease were associated with acidification in a random forest model. Urease cleaves urea into ammonia and carbon dioxide, however the role of urease in the physiology of Lachnospiraceae is unknown. We demonstrate that urease-encoding Blautia show urea-dependent changes in SCFA production, acidification, growth, and, strikingly, urease encoding Blautia directly incorporate the carbon from urea into SCFAs. In contrast, ureolytic Klebsiella pneumoniae or Proteus mirabilis do not show the same urea-dependency or carbon salvage. In agreement, the combination of urease and acetogenesis functions is rare in gut taxa. We find that Lachnospiraceae urease and acetogenesis genes can be co-expressed in healthy individuals and colonization of mice with a ureolytic Blautia reduces urea availability in colon contents demonstrating Blautia urease activity in vivo. In human and mouse microbial communities, the acetogenic recycling of urea carbon into acetate by Blautia leads to the incorporation of urea carbon into butyrate indicating carbon salvage into broader metabolite pools. Altogether, this shows that urea plays a central role in the physiology of health-associated Lachnospiraceae which use urea in a distinct manner that is different from that of ureolytic pathogens.

Calcium Imaging in Vivo: How to Correctly Select and Apply Fiber Optic Photometric Indicators

Fiber-photometric is a novel optogenetic method for recording neural activity in vivo, which allows the use of calcium indicators to observe and study the relationship between neural activity and behavior in free-ranging animals. Calcium indicators also convert changes in calcium concentration in cells or tissues into recordable fluorescent signals, which can then be observed using the system of fiber-photometric. To date, there is a paucity of relevant literature on the proper selection and application of fiber-photometric indicators. Therefore, this paper will detail how to correctly select and apply fiber-photometer indicators in four sections: the basic principle of optical fiber photometry, the selection of calcium fluorescent probes and viral vector systems, and the measurement of specific expression of fluorescent proteins in specific tissues. Therefore, the correct use of suitable fiber optic recording indicators will greatly assist researchers in exploring the link between neuronal activity and neuropsychiatric disorders.

Targeting capabilities of engineered extracellular vesicles for the treatment of neurological diseases

Recent advances in research on extracellular vesicles have significantly enhanced their potential as therapeutic agents for neurological diseases. Owing to their therapeutic properties and ability to cross the blood-brain barrier, extracellular vesicles are recognized as promising drug delivery vehicles for various neurological conditions, including ischemic stroke, traumatic brain injury, neurodegenerative diseases, glioma, and psychosis. However, the clinical application of natural extracellular vesicles is hindered by their limited targeting ability and short clearance from the body. To address these limitations, multiple engineering strategies have been developed to enhance the targeting capabilities of extracellular vesicles, thereby enabling the delivery of therapeutic contents to specific tissues or cells. Therefore, this review aims to highlight the latest advancements in natural and targeting-engineered extracellular vesicles, exploring their applications in treating traumatic brain injury, ischemic stroke, Parkinson's disease, Alzheimer's disease, amyotrophic lateral sclerosis, glioma, and psychosis. Additionally, we summarized recent clinical trials involving extracellular vesicles and discussed the challenges and future prospects of using targeting-engineered extracellular vesicles for drug delivery in treating neurological diseases. This review offers new insights for developing highly targeted therapies in this field.

Improved immunocompatibility of active targeting liposomes by attenuating nucleophilic attack of cyclic RGD peptides on complement 3

One of the challenges for the clinical translation of active targeting nanomedicines is the adverse interactions between targeting ligands and blood components. Herein, a novel regularity, which reveals the interactions between cyclic RGD (Arg-Gly-Asp) peptide-modified liposomes and complement components in blood, is reported. As the nucleophilicity of arginine guanidine group within the cyclic RGD-like peptide increases, targeting liposomes potentiate complement cascade via the amplification loop of complement 3 (C3), ultimately leading to accelerated blood clearance, increased deposition in the reticuloendothelial system (RES) organs, enhanced immune responses, and potential side effects. By appropriately reducing the nucleophilicity of guanidine group, cyclic R2 peptide is designed for modification of liposomes to target integrin αvβ3. Compared to the widely used targeting molecule c(RGDyK), R2 eliminates the negative effects of C3 opsonization and specific antibody production, significantly improves the in vivo immunocompatibility of targeting liposomes, and demonstrates superior anti-tumor efficacy in mouse models of orthotopic breast cancer and glioma. Thus, the proposed regularity of interactions between guanidine nucleophilicity and C3, along with the successful application of the low complement activation capacity targeting ligand R2, provides new insights for addressing challenges related to complement activation in the clinical translation of active targeting nanomedicines.

Living therapeutics: Precision diagnosis and therapy with engineered bacteria

Bacteria-based therapy has emerged as a promising strategy for cancer treatment, offering the potential for targeted tumor delivery, immune activation, and modulation of the tumor microenvironment. However, the unpredictable behavior, safety concerns, and limited efficacy of wild-type bacteria pose significant challenges to their clinical translation. Recent advancements in synthetic biology and chemical engineering have enabled the development of precisely engineered bacterial platforms with enhanced controllability, targeted delivery, and reduced toxicity. This review summarize the current progress of engineered bacteria in cancer therapy. We first introduce the theoretical underpinnings and key advantages of bacterial therapies in cancer. Subsequently, we delve into the applications of genetic engineering and chemical modification techniques to enhance their therapeutic potential. Finally, we address critical challenges and future prospects, with a focus on improving safety and efficacy. This review aims to stimulate further research and provide valuable insights into the development of engineered bacterial therapies for precision oncology.

A heterojunction-engineering nanodrug with tumor microenvironment responsiveness for tumor-specific cuproptosis and chemotherapy amplified sono-immunotherapy

Cuproptosis has recently identified as a unique copper-dependent cell death mechanism that may provide new opportunities for improving the therapeutic effect of tumor therapy through triggering efficient adaptive immune responses. However, the poor delivery efficiency and non-tumor-specific release of Cu ions would restrict the potential clinical applications of cuproptosis inducers. Herein, we report for the first time the development of hollow Cu2-xSe nanocubes as the tumor microenvironment (TME)-responsive drug delivery systems and cuproptosis inducers for tumor-specific chemotherapy and cuproptosis. The presence of Cu vacancy endows Cu2-xSe with excellent sonodynamic and chemodynamic activity. The hollow Cu2-xSe nanocubes with TME-responsive degradation behaviors are further utilized to load graphene quantum dot (GQD) nanodrugs to form GQD/Cu2-xSe heterojunctions for achieving tumor-specific chemotherapy. The heterojunction-fabrication GQD/Cu2-xSe exhibits amplified ROS generation capabilities and improved TME regulation ability owing to the optimized electron-hole separation kinetics. More importantly, the significant increase in ROS levels and efficient cuproptosis could reverse the immunosuppressive TME and induce immunogenic cell death that stimulates strong systemic immune responses to eliminate tumors. Collectively, this work presents an innovative strategy for the utilization of TME-responsive cuproptosis inducers for tumor-specific chemotherapy and cuproptosis augmented sono-immunotherapy.

An "all-in-one" therapeutic platform for programmed antibiosis, immunoregulation and neuroangiogenesis to accelerate diabetic wound healing

Pathological microenvironment of diabetes induces a high risk of bacterial invasion, aggressive inflammatory response, and hindered neuroangiogenesis, leading to retarded ulcer healing. To address this, an "all-in-one" therapeutic platform, named MZZ, was constructed by loading maltodextrin onto a MOF-on-MOF structure (with ZIF-67 as the core and ZIF-8 as the shell) through a hybrid process of solvent treatment and electrostatic adsorption. Maltodextrin acts as a target to bind surrounding bacteria, and ZIF-8 as well as ZIF-67 responsively release Zn and Co ions, which not only kill most bacteria, but also improve the phagocytosis and xenophagy of M1 macrophages by up-regulating the expression levels of ATG5, Bcl1 and FLT4, helping the residual bacterial clearance. In inflammatory stage, MZZ scavenges extracellular and intracellular ROS by valence transition between Co2+ and Co3+, and promote M1 macrophages to transform into M2 phenotype. In tissue reconstruction stage, the synergistic effect of Zn and Co ions as well as cytokines secreted by macrophages up-regulates cell vitality and biofunctions of endotheliocytes, neurocytes and fibroblasts. The programmed effects of MZZ on antibiosis, anti-inflammatory and neuroangiogenesis to accelerate wound repair are further confirmed in an infected diabetic model, and this "all-in-one" platform shows great clinical application potential.

Dual-miRNA guided in-vivo imaging and multimodal nanomedicine approaches for precise hepatocellular carcinoma differentiation and synergistic cancer theranostics using DNA hairpins and dual-ligand functionalized zirconium-MOF nanohybrids

As one of the most common and heterogeneous liver malignancies, hepatocellular carcinoma (HCC) remains a significant clinical challenge due to the lack of biomarkers for early diagnosis, challenges in accurate subtyping, and limitations of current therapeutic strategies with poor efficacy. Herein, based on DNA hairpin probes and dual-ligand zirconium (Zr)-based metal-organic frameworks (DMOFs), the multifunctional nanohybrids (DMOF@MnCO@CuS@Hairpin probe, DMCH) were developed to overcome these diagnostic and therapeutic obstacles. Two improved DNA molecular beacons and APE1 enzyme within HCC cells were utilized for sensitive miRNA imaging in vivo with high accuracy to differentiate HCC subtypes precisely. Furthermore, this "all-in-one" theranostic platform not only facilitates the generation of active oxygen species and conversion of near-infrared light into heat, but also releases carbon monoxide to inhibit the expression of HSP70 protein to improve photothermal (PTT) therapy efficiency during laser radiation, which enables PTT, photodynamic (PDT), chemodynamic (CDT), and gas therapy (GAT) for HCC treatment simultaneously. The developed nano-theranostics platform provides a novel way for efficient early screening, diagnosis, and intervention of HCC, and paves the path for future "bench-to-bedside" design of theranostics.

NIR-II AIEgen with high photothermal efficiency for mild PTT: Optimized natural killer cell spatial distribution for boosted immune response

Organic photothermal agents (PTAs) with high photothermal conversion efficiency (PCE) and biocompatibility are ideal for mild photothermal therapy (PTT), which can selectively eliminate tumor cells and elicit an active immune response. However, the challenge lies in developing PTAs with high PCE, and the impact of PTT-induced temperature gradients on the cytolytic potential of natural killer (NK) cells against tumor cells has yet been investigated. Herein a novel NIR-II aggregation-induced emission (AIE) molecule named C12T-BBT is proposed by conjugating an electron donor TPA with a strong electron acceptor BBT, using a long alkyl chain (C12) substituted thiophene as π-bridge. By doing this, C12T-BBT has a relative planar structure to ensure a high extinction coefficient, while the long alkyl chain restricts the π-π interaction and provides more room for molecular motion in excited state. Together, these design strategies assure C12T-BBT with a high PCE of 84.7 %. In vivo experiments exhibit favorable NIR-II imaging and tumor elimination using water-soluble cRGD@C12T-BBT nanoparticles. The application of mild PTT results in an effective induction of NK cell response in terms of shortening its distance with tumor cells from 25.6 μm to 10.6 μm, characterized using a machine-learning based spatial analysis, thereby enhancing the efficacy of cancer therapy. Therefore, this work provides evidence for a novel combined anti-tumor strategy of aligning mild PTT and NK cell immunotherapy by illustrating crucial optimization of NK-tumor intercellular proximity in mild PTT.

Immunomodulatory bioadhesive technologies

Bioadhesives have found significant use in medicine and engineering, particularly for wound care, tissue engineering, and surgical applications. Compared to traditional wound closure methods such as sutures and staples, bioadhesives offer advantages, including reduced tissue damage, enhanced healing, and ease of implementation. Recent progress highlights the synergy of bioadhesives and immunoengineering strategies, leading to immunomodulatory bioadhesives capable of modulating immune responses at local sites where bioadhesives are applied. They foster favorable therapeutic outcomes such as reduced inflammation in wounds and implants or enhanced local immune responses to improve cancer therapy efficacy. The dual functionalities of bioadhesion and immunomodulation benefit wound management, tissue regeneration, implantable medical devices, and post-surgical cancer management. This review delves into the interplay between bioadhesion and immunomodulation, highlighting the mechanobiological coupling involved. Key areas of focus include the modulation of immune responses through chemical and physical strategies, as well as the application of these bioadhesives in wound healing and cancer treatment. Discussed are remaining challenges such as achieving long-term stability and effectiveness, necessitating further research to fully harness the clinical potential of immunomodulatory bioadhesives.

A transcatheter mitral valve clip with a central filler for mitral valve regurgitation

Despite the advantages of transcatheter edge-to-edge repair (TEER) devices for treating mitral regurgitation, challenges such as difficulties in leaflet grasping and clip dislodgement remain in clinical practice. In this study, we present the first detailed disclosure of a novel transcatheter mitral valve clip, the DragonFly, highlighting its material composition, design features, and associated benefits. The valve clip is constructed of nickel-titanium alloy, stainless steel, cobalt-chromium alloy, and polyethylene terephthalate, incorporating adjustable arms, grippers, and a unique central filler. The central filler, made of nitinol, offers remarkable compressibility and shape recovery. The whole valve clip can endure over 400 million fatigue cycles and ensure a robust grasp on valve leaflets at varying angles. The clip presents sufficient grasping force to prevent valve dislodgement, and the adjustable design accommodates various patient anatomies. Comprehensive biocompatibility assessments confirmed adherence to ISO 10993 standards through in vitro and in vivo experiments, including large-animal studies. The results demonstrated that the valve clip successfully creates a stable double-orifice structure without negatively impacting cardiac hemodynamics and has good biocompatibility. Overall, the DragonFly valve clip constitutes a technological advancement in the field of minimally invasive interventions for mitral valve disease, offering more treatment options for high-risk patients.

A novel fluorescent sensor for imaging of viscosity and ClO- in plant cells and zebrafish

Viscosity and hypochlorite (ClO-) are two crucial microenvironmental species that play significant roles in biological activities. Their abnormal levels are closely associated with numerous common diseases. Therefore, accurate and real-time detection of hypochlorite and viscosity related to inflammatory microenvironment conduces to elucidate the pathogenesis and further diagnose the disease. In this work, based on the strategy of the phenothiazine (PTZ)-dicyanoisophorone (DCO) dyad system, a new dual-response fluorescent sensor (PBI) was successfully constructed for the simultaneous detection and visualization of viscosity and hypochlorite (ClO-) both in vitro and in vivo. The free sensor emits weak fluorescence in aqueous solution thanks to twisted intramolecular charge transfer (TICT) and photoinduced electron transfer (PET). However, in a high-viscosity system, the fluorescence emission of the sensor at 459 nm was significantly enhanced. Upon introduction of ClO- in aqueous buffer solution, the PBI exhibited apparent fluorescence enhancement at 577 nm, and showed large Stokes shift (177 nm). The fluorescence responsive mechanism was confirmed using HRMS, 1H NMR and DFT calculation analysis. Onion and lotus root cells imaging of PBI towards ClO- was implemented. Furthermore, PBI has been successfully applied to the fluorescence imaging of viscosity and exogenous/endogenous hypochlorite in zebrafish.

A novel fluorescence and colorimetric dual sensing system for rapid and sensitive detection of histidine based on TSPP-CA

Histidine (His) plays an important role in human health and life activities. It will harm human health when His intake is insufficient or excessive. Its residue also will pollute the natural environment. Therefore, establishing a reliable and sensitive method for detecting histidine is particularly important. However, most of the existing detection methods of His rely on the single change of single signal, which are susceptible to interference from testing environmental factors and prone to generating false positive results. In contrast, the fluorescence and colorimetric dual-signal sensing system can not only effectively improve the reliability of detection, but also significantly reduce the risk of false positives. Therefore, the dual-signal sensing system has gradually become the research hotspot. Based on this, 5,10,15,20-tetra-(4-sulfophenyl) porphyrin (TSPP) was selected as the fluorescence and colorimetry dual-signal probe for the rapid detection of His in this study. Since TSPP could interact with many substances due to the specificity of molecular structure, it is the best choice to build an "ON-OFF-ON" sensing system in order to improve the specificity of the sensing system. Therefore, citric acid (CA) as an intermediate based on TSPP probe was successfully developed fluorescence and colorimetric dual-sensing system for the quantitative detection of histidine in real samples. The signal of the dual sensing system was "turned on" when the red TSPP solution obtained the fluorescence emission wavelength of 642 nm at the 514 nm optimal excitation wavelength and the UV-Vis absorption at 413 nm, respectively. The fluorescence intensity and absorbance of TSPP gradually decreased with the introduction of CA. At this time, the signal of the dual-sensing system became "turned off", and the color of the solution changed from light pink to light green. The quenched fluorescence intensity and absorbance, however, was restored upon the introduction of histidine into the system. Simultaneously, the color of the solution changed from light green to light pink, and the dual-sensing system became "turned on". Therefore, a novel fluorescence and colorimetric dual-signal sensing system based on TSPP was proposed for histidine detection. The results indicated that the linear ranges of the fluorescence sensing system were 8.34 × 10-6 M - 1.51 × 10-4 M and 1.85 × 10-4 M - 1.4 × 10-3 M with detection limits of 0.282 μM and 10.91 μM (LOD, S/N = 3), respectively. The linear range of the colorimetric sensing system was 2.04 × 10-4 M-4.35 × 10-4 M with a detection limit of 11.97 μM (LOD, S/N = 3). Meanwhile, the dual-sensing system provided a promising platform for practical samples sensing applications.

Unraveling an excited state intramolecular double proton transfer pathway in 2,5-bis(benzoxazole-2-yl)benzene-1,4-diol derivatives

Organic molecules exhibiting excited-state intramolecular double proton transfer (ESIDPT) have garnered significant research interest, largely driven by their prevalence in nature and the unique luminescent properties associated with this phenomenon. This study presents a detailed theoretical investigation into the dynamic mechanism of both single and dual cooperative Proton transfer (PT) in the first excited singlet (S1) state of 2,5-bis(benzoxazole-2-yl)-1,4-dihydroxybenzene derivatives. The analysis meticulously incorporates solvent effects, specifically those of dichloromethane, to provide a comprehensive understanding of the PT processes. The occurrence of the ESIDPT process was confirmed by integrating infrared (IR) vibrational spectra, frontier molecular orbital analysis, and reduced density gradient (RDG) analysis. Additionally, the potential energy surfaces (PESs) for the ground (S0) and S1 states revealed a synergistic interaction between single and dual ESIPT processes within the S1 state. Furthermore, variation in the charge distribution, resulting from the coupling of photoinduced electron transfer with ESIPT involving the DPA group, led to distinct PT propensities for the O1 and O4 atoms. Consequently, these configurations are unable to undergo simultaneous proton transfer, as demonstrated by the construction of a potential energy surface. In addition, the corresponding PT PESs show that the ESIPT reaction for Zinhbo-9 is much easier for the Zinhbo-5 modified with a t-Bu group, which affect O4-H5···N6 hydrogen bond. These theoretical computations provide a robust explanation of the observed experimental phenomena and suggest potential pathways for future advancements and applications of ESIDPT molecules.

Rod-like D-π-A-π-D Schiff base liquid crystal for continuous ion sensing, live cell imaging, fingerprint imaging and WLED

A series of rod-like D-π-A-π-D Schiff base liquid crystals were synthesized, featuring a BTD central acceptor unit connected to N-trialkoxybenzyl carbazole terminal donor groups through imine linkages at both ends. The series includes hydroxyl-containing derivatives BOH/n (n = 12, 14, 16), hydroxyl-free BH/12, and the corresponding boron complex BOB/12 derived from BOH/12. Among them, BOH/n can self-assemble into the Colrec/c2mm LC phase, while BH/12 can self-assemble into the Colrec/p2mm LC phase, and boron complex BOB/12 can self-assemble into the Colhex/p6mm LC phase. Further compound BOH/n can self-assemble into a luminescent organic gel in organic solvents with wrinkled sheet morphologies. Photophysical studies revealed that all compounds showed J-aggregation form. All compounds except BOB/12 exhibited the AIEE effect. The fluorescence quantum yield in solution and the absolute solid quantum yield of BOB/12, reached as high as 85 % and 41 % respectively which is 14 and 3 times higher than those of the corresponding BOH/12. Based on the ion recognition result of BOH/12, a non-conventional sequential detection method for the identification sequence of Fe3+-Cu2+-Al3+ was constructed and applied successfully as test paper detection. Additionally, BOH/12 was successfully utilized as live cell imaging, potential fingerprint imaging, and white light emitting devices (WLED).

Bimetallic SERS platform with femtomolar sensitivity for in situ monitoring of catalytic reactions

We developed a gold-silver bimetallic surface-enhanced Raman scattering (SERS) chip (AuNPs@AuAg NSs island array chip) that combines excellent SERS enhancement with in situ catalytic properties. This platform exhibits superior plasmonic catalytic capabilities, enabling rapid in situ monitoring of redox reactions without the need for chemical reductants. Additionally, under simulated sunlight, the chip achieved effective degradation of methylene blue (MB) molecules, with a removal rate of 95.65 %, demonstrating its potential for environmental safety applications. The chip's uniform and dense SERS hotspots allow for the detection of pollutants at extremely low concentrations (as low as 10-15 M), offering a powerful tool for trace-level detection of hazardous substances. This work highlights the potential of such nanostructures for in situ monitoring of catalytic reactions and pollutant degradation, as well as for rapid, non-destructive, and high-throughput detection of ultra-low concentrations of analytes.

The enhanced excited-state intramolecular proton transfer energy barrier of flavonols induced by deprotonation

The barrierless excited-state intramolecular proton transfer (ESIPT) is believed to account for the non-radiative decays of flavonols composed of 5-hydroxyl group. However, the ESIPT mechanisms of flavonol anions have never been elucidated. In this work, by using the time-dependent density functional theory (TDDFT) calculations, we have determined the barrierless ESIPT in kaempferol and galangin, in agreement with their non-emissive properties. In contrast, deprotonation at the position 7 of them is demonstrated to decrease the basicity of proton acceptor and acidity of proton donor in the excited state, largely increasing the ESIPT barrier and leading to the fluorescence emission from the normal state. A further deprotonation of mono-deprotonated kaempferol is inferred to induce blue shifted emission. These results elucidate the nature of emissive flavonol anions and give a deep insight into the optical properties of flavonols in different matrices.

Theoretical and experimental spectroscopic analysis of new phenanthrene based compounds for organic solar cell device

This paper presents a combined theoretical and experimental spectroscopic investigation of new phenanthrene derivative compounds, having some new remarkable structural features. Their chemical synthesis was achieved by efficient Mizoroki-Heck coupling. The corresponding properties, including UV-Vis absorption, photoluminescence, thermal stability and electrochemistry data, were deeply elucidated and presented. Besides, theoretical geometry optimization and different simulated spectra were performed via Density Functional Theory (DFT) method, in which both the gas and liquid phases characteristic are elucidated. A representative set of electrons donating groups (methoxy) and withdrawing groups (cyano) are introduced in the main chemical backbone, to elucidate the role of lateral and side backbone substituents. Overall, the theoretical calculation was carried to examine some fundamental parameters: electric dipole moment (μ), EHOMO, ELUMO, electronegativity (χ), global chemical hardness (η), global softness (σ), matched the experimental measurements, showing a good correlation. Among them, some useful information about the interaction of these organic systems with surfaces of SWCNT has been calculated through conceptual DFT. The C2:SWCNT(5,5) molecular blend with two different orientations to the nanotube axis, as active layer for conventional solar cell device, has been investigated. The characteristic parameters of the active layer and the device were consolidated by TD-DFT computational data and SILVACO-ATLAS software simulation results. Compatible energy models have been proposed simulating the electric response and band diagram of such optoelectronic devices.

QCM biosensor based on silver aggregates and DNA ligase for ultrasensitive detection of BRAF-V600E single mutant gene in melanoma

The detection of BRAF-V600E gene mutations plays a pivotal role in the diagnosis, prediction, and therapeutic intervention of melanoma. In this work, a quartz crystal microbalance (QCM) biosensor was developed to detect the BRAF-V600E point mutation. The gold electrode of the QCM was incubated with a thiol (-SH) modified capture probe, subsequently treated with polyethylene glycol (PEG) to obstruct nonspecific binding sites on the electrode. Subsequently, the target sequence BRAF-V600E (alternatively referred to as BRAF) along with the detection probe were incubated to construct a functionalized layer. T4 DNA ligase was introduced to facilitate the connection between the detection and capture probes, thereby forming either elongated or abbreviated DNA chains. Ultimately, silver aggregates (AgAs) were formed and bound to DNA bases and exert a significant influence on the sensor's frequency. In instances where the target sequence is BRAF-V600E, the frequency shift is markedly higher in comparison to BRAF, thereby facilitating a clear distinction between the two. The developed biosensor exhibited a linear detection range of 1 pM-10 nM for BRAF-V600E, with a detection limit of 0.73 pM and an R2 value of 0.9923. The accuracy of the QCM method was rigorously validated through a comparative analysis with quantitative polymerase chain reaction (qPCR). This study holds significant implications for the early detection and precise of melanoma.

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.

Nanocarrier-mediated siRNA delivery: a new approach for the treatment of traumatic brain injury-related Alzheimer's disease

Traumatic brain injury and Alzheimer's disease share pathological similarities, including neuronal loss, amyloid-β deposition, tau hyperphosphorylation, blood-brain barrier dysfunction, neuroinflammation, and cognitive deficits. Furthermore, traumatic brain injury can exacerbate Alzheimer's disease-like pathologies, potentially leading to the development of Alzheimer's disease. Nanocarriers offer a potential solution by facilitating the delivery of small interfering RNAs across the blood-brain barrier for the targeted silencing of key pathological genes implicated in traumatic brain injury and Alzheimer's disease. Unlike traditional approaches to neuroregeneration, this is a molecular-targeted strategy, thus avoiding non-specific drug actions. This review focuses on the use of nanocarrier systems for the efficient and precise delivery of siRNAs, discussing the advantages, challenges, and future directions. In principle, siRNAs have the potential to target all genes and non-targetable proteins, holding significant promise for treating various diseases. Among the various therapeutic approaches currently available for neurological diseases, siRNA gene silencing can precisely "turn off" the expression of any gene at the genetic level, thus radically inhibiting disease progression; however, a significant challenge lies in delivering siRNAs across the blood-brain barrier. Nanoparticles have received increasing attention as an innovative drug delivery tool for the treatment of brain diseases. They are considered a potential therapeutic strategy with the advantages of being able to cross the blood-brain barrier, targeted drug delivery, enhanced drug stability, and multifunctional therapy. The use of nanoparticles to deliver specific modified siRNAs to the injured brain is gradually being recognized as a feasible and effective approach. Although this strategy is still in the preclinical exploration stage, it is expected to achieve clinical translation in the future, creating a new field of molecular targeted therapy and precision medicine for the treatment of Alzheimer's disease associated with traumatic brain injury.

Deep machine learning-assisted MOF@COF fluorescence/colorimetric dual-mode intelligent ratiometric sensing platform for sensitive glutathione detection

Glutathione (GSH) levels have been linked to aging and the pathogenesis of various diseases, highlighting the necessity for the development of sensitive analytical methods for GSH to facilitate disease diagnosis and treatment. In this study, we synthesized a novel core-shell material, UiO@TBTA, by in-situ growing TFPB-TAPA COF on UiO-66-NH2 through a Schiff base reaction. The resulting composite capitalize on the advantages of both materials, demonstrating excellent stability, large specific surface area, and abundant active functional groups while preserving superior crystallinity. Notably, this strategy effectively reduces the occurrence of aggregation-caused quenching (ACQ) in COFs. Due to the inner filter effect and hydrogen bonding interactions between UiO@TBTA and GSH, a specific ratiometric fluorescence detection of GSH was achieved in the range of 0.1-7 μM, with a limit of detection (LOD) of 0.0685 μM. In addition, due to the sensitive color change of the sensing material from orange to black caused by GSH, a proportional colorimetric sensing strategy has also been proposed, enabling the detection of GSH within the range of 1-200 μM. What's more, two intelligent artificial neural networks models were constructed with the help of machine learning that can quickly, accurately, and sensitively determine the concentration of GSH based on fluorescence images and color photographs respectively. Our work represents the first study utilizing MOF@COF composite for the multimodal detection of GSH, thus providing a novel strategy for the multimodal detection of the target analyte. Prospectively, the construction of the fluorescence/colorimetric dual-mode intelligent ratiometric sensing platform using deep machine learning holds great promise for real-time monitoring.

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.

Insight into soot oxidation performance and kinetics of novel Ce/La modified Cs-V based non-noble metal catalysts

The catalytic diesel particulate filter (CDPF) is the most widely used after-treatment device for controlling diesel engine soot emissions. The development of cost-effective catalysts is crucial for diesel engines to comply with future ultra-low emission regulations. This paper studies a new type of Ce/La modified Cs-V non-noble metal CDPF catalyst. Three test catalysts (Cs-V, Cs-V-5 %Ce, and Cs-V-5 %La) were formulated to explore the physical properties, activity, and sulfur resistance through XRD, SEM, XPS, and TPO tests. And TGA tests with different catalyst-to-soot mass ratios were designed to analyze the reaction kinetics. The results show that the soot oxidation process is divided into three stages: slow oxidation, rapid oxidation, and soot burnout. SEM and XRD results show that, compared with Ce doping, La-doped catalysts have less damage to the microstructure of the first active component, Cs2V4O11. XPS results show that the introduction of Ce and La is beneficial to the formation of oxygen vacancies and lattice distortion, increasing the proportion of active oxygen species, thereby improving the soot oxidation activity, among which La-doped active oxygen species have the highest proportion (94 %). And the Cs-V-5 %La catalyst has the best effect on improving the soot conversion of the three stages. The fresh state has the best low-temperature activity index, the lowest characteristic temperature (T50 of 374 °C) and activation energy (115.01 kJ/mol), and excellent sulfur resistance. The soot conversion and oxidation speed of the three stages decreases, duration lengthens, and activation energy increases by more than 100 kJ/mol as catalyst-to-soot mass ratios decrease.

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.

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.

Dual-palindrome-incorporated hand-in-hand self-linking bidirectional DNA amplifier within exogenous near-infrared light stimulation for high-performance imaging in living biosystems

Although the potency of DNA amplifiers-constructed biosensors for imaging disease biomarkers in living biosystems, they continue to face two challenges: (i) intricate multi-pathway amplification cascades in biosensing designs and (ii) suboptimal detection precision due to uncontrollable pre-activation during bio-delivery. In this contribution, we have brought the following viable resolutions. First, a catalytic hairpin assembly (CHA) routine is incorporated with a dual-palindrome that works like two pairs of hands to self-link CHA-amplified intermediate nucleic acids units, enabling a streamlined two-round signal intensification to enhance sensitivity. Thereafter, one DNA component is conducted with the insertion of a photocleavage-coupler, by which the biosensor can be precisely stimulated via exogenous 808 nm near-infrared (NIR) light-converted upconversion luminescence to recognize the analysis subjects in a controllable action. With the aim of conceptual presentation, this dual-palindrome-incorporated hand-in-hand self-linking bidirectional DNA amplifier stimulated by exogenous NIR light exhibits ultra-sensitive solution detection of various cancers-associated microRNA-155. More deeply, the biosensing toolbox can serve for high-performance imaging of low-abundance biomarkers at the real-word context of living cells and in vivo, boosting the advancement of DNA amplifiers in medical diagnostics.

Domino-like turn-on chemiluminescence amplification: Opening a gateway through proximal-imidazole species formation and metal-ligand complexation

Due to their extremely low background signal and high sensitivity, the chemiluminescence (CL) probes have received a great attention in various chemical and biological applications. However, the lack of selectivity is still a challenging task. As an innovative topic of research, in this work we developed a domino-like turn-on CL reaction through proximal-imidazole species for the first time. The oxidation reaction of N-(2H-[1,2,4]thiadiazolo[2,3-a]pyridine-2-ylidene)benzamide (1) by hydrogen peroxide found to promoted by a domino-like reaction between proximal imidazole species and the Co2+-1 complex formation which accompanied by a dramatically turn-on emission. In the way of explaining the possible mechanism, the application of density functional theory (DFT) studies revealed that there are three possible pathways for the reactions between precursor 1 and HOO- in the presence of imidazole to produce the oxidized isomers. The strongest interaction found to occur in pathway 3, in which the sulfur atom was oxidized, while there was some repulsion between HOO- and 1, due to the effects of two different charges in pathways 1 and 2. To confirm tits applicability, the CL system was successfully applied to highly selective quantification of vitamin B12 in some real samples. The linear dynamic range was achieved from 0.08 to 34 ng mL-1 and the detection limit was evaluated as 0.028 ng mL-1. This new method introduced fluorescence selectivity and CL sensitivity in single technique. It was finally anticipated that the CL amplification through proximal-imidazole species possesses a great potential on tuning various color-emissions based on different metal-ligand complex formations studied.

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.

A theranostic three-photon fluorescent Mn complex with mixed double and triple bond for drug-induced liver injury: ONOO- activatable and CO-releasing

Recent research indicates that it is crucial to understand the relationship between peroxynitrite (ONOO-) levels and the progression of drug induced liver injury (DILI). Therefore, we present an ONOO- activatable probe, Mn(tpy)(CO)2Br, which exhibits enhanced three photon excitation fluorescence after specific recognizing ONOO-. The fluorescence enhancement mechanism is to format Mn-O double and triple bonds with a mixed oxidation state. Additionally, Mn(tpy)(CO)2Br releases carbon monoxide (CO) with ONOO- concentration-dependent, which increases the intracellular glutathione content by regulating Nrf2 and HO-1 proteins, thereby reducing the overall level of oxidative stress. Thanks to the advantages of low background interferences and high resolution of three-photon imaging, Mn(tpy)(CO)2Br can clearly reflect liver inflammation and effectively mitigate liver damage under NIR II excitation in vivo. This promising complex could pave a way for the development of multifunctional probes for the diagnosis and treatment of DILI.

SERS detection of analgesics in serum based on Ag nanocubes for perioperative monitoring

Prompt and personalized perioperative analgesia management relies on sensitive and convenient monitoring of analgesics. We report a strategy for sensitive and reproducible SERS detection of analgesics based on Ag nanocubes, which have abundant intragranular hot spots on sharp corners and interparticle hot spots between gaps. Both theoretical simulations and R6G detection experiments indicated that the enhancement factor of Ag nanocube SERS platform reach to 106 level. Quantitative and reproducible determination capabilities of this platform for six different analgesics with LOD as low as 500 pg mL-1 were verified. Pharmacokinetic experiment of fentanyl in rat serum samples by SERS detection within 4 h presented consistent results with the UHPLC-MS/MS method. Valid examples of SERS detection for single or multiple analgesics in clinical patients' serums further proved the feasibility of this platform for perioperative analgesic monitoring.

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.

Direct detection of 3-nitrotyrosine reveals the nitration of proteins in laboratory exposure and ambient aerosols

Tyrosine residues in proteins can be nitrated to form 3-nitrotyrosine (3-NT) under the influence of ozone (O3) and nitrogen dioxide (NO2) in the air, which may introduce health impacts. A selective and sensitive enzyme-linked-immunoassay (ELISA) method was developed to determine 3-NT in modified model protein (bovine serum albumin, BSA) and ambient aerosol samples. The nitration degrees (NDs) of BSA in the exposure experiments with different durations were detected by both the ELISA and spectrophotometric methods (i.e., NDELISA and NDSEC-PDA), which show good coincidence. The kinetic investigation by both ΔNDELISA and ΔNDSEC-PDA in the exposure experiments shows that the rate coefficients (k) of the pseudo-first-order kinetic rate reactions of protein nitration were comparable. These results indicate that direct detection of 3-NT by the ELISA method can be applied for laboratory exposure samples analysis for kinetic studies. Based on the selective detection of 3-NT, NDELISA provides a promising measure for the assessment of ND in model proteins. 3-NT was also measured in PM2.5 samples in summer in Guangzhou, southern China, ranging from 10.1 to 404 pg/m3, providing clear evidence of protein nitration in ambient aerosols. We further proposed that 3-NT/protein can be used as a proxy to evaluate protein nitration in ambient aerosols. A significant correlation was observed between 3-NT/protein and O3, confirming the crucial role of O3 in protein nitration. Our results show that the direct detection of 3-NT by the ELISA method can be more widely applied in the laboratory and field-based studies for understanding the mechanisms of protein nitration.

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.

Robust streamlined two-dimensional offline coupling of asymmetrical flow field-flow fractionation and capillary electrophoresis for the separation and quantitation of a five-component submicron particle mixture

Characterization of submicrometer particles by size and surface charge is critical to understanding their property and functionality in industrial formulations. Although the recently reported offline coupling of asymmetrical flow field-flow fractionation and capillary electrophoresis (AF4×CE) shows success in separating a five-component submicrometer particle mixture based on size and mobility, it is a long and tedious process requiring extensive method development and instrument expertise. Moreover, it suffers from low throughput and ambiguity in large particle identification, limiting its widespread acceptance and application in industry. Here we report a new AF4×CE-laser-induced fluorescence (LIF) method which involves minimal method development and eliminates both the large sample injection and subsequent on-capillary stacking in CE separation, to significantly streamline separation and improve analysis throughput. Comprehensive characterization of eight fluorescently labeled five-component submicrometer particle mixture standards, at the concentration ratio of 200 : 200: 133 : 133: 334 and the total concentration level of 1000-10,000 mg/L, and a random sample can be performed within several days. In the lowest-concentration standard, as few as 2.97 × 102 particles at the peak center can be detected on the two-dimensional plot for the 500 nm particles, indicating extremely high detection sensitivity. By eliminating the overstacking issue, large particles can be unambiguously identified on the 2D plot based on the migration time. AF4-light scattering (LS) quantitation demonstrates good accuracy for the artificial five-component sample even when the five components are not completely separated. Moreover, AF4×CE-LIF quantitation is explored for future more challenging mixtures requiring higher separation capacity and resolution.

Construction of a heterojunction between Ni/Al layered double oxides and CdS quantum dots for efficient photocatalytic hydrogen production

The Ni/Al layered double oxide (Ni/Al-LDO) is a promising photocatalyst because of the high surface area and abundant active sites. However, the application of Ni/Al-LDO for photocatalytic hydrogen evolution is hindered by the unclarity of the optimized microstructure and limited light absorption. In this work we report the structural evolution from Ni/Al layered double hydroxides (Ni/Al-LDH) to Ni/Al-LDO, which is able to achieve a precise regulation of the layered structure with abundant acid sites for photocatalysis. Further, CdS quantum dots (QDs) are in-situ grown on the sheet-like Ni/Al-LDO to obtain a close contact 0D/2D CdS-Ni/Al-LDO heterojunction. CdS-Ni/Al-LDO exhibits a hydrogen evolution efficiency of 20.3 mmol/g/h and an apparent quantum yield (AQY) of 22.2 % at a wavelength of 450 nm. The superior performance is attributed to the synergistic effects of abundant Lewis and Brønsted acid sites of Ni/Al-LDO, the layered structure with a high specific surface area and the heterojunction between Ni/Al-LDO and the CdS QDs.

Hydrophobic eutectic solvents functionalized graphene oxide nanocomposites: An engineered solution for antibiotic remediation

Antibiotic contamination in aquatic environments threatens public health and ecological balance. This study introduces a novel nanocomposite by impregnating graphene oxide (GO) with a hydrophobic deep eutectic solvent (HDES). The novel nanocomposite was used to remove meropenem (MEM) antibiotic from aqueous solutions effectively. Ten natural HDESs were screened, and thymol:levulinic acid-impregnated GO nanocomposite GO@Thy:LevA (1:3) was the best-performing adsorbent. The successful integration of HDES into GO nanocomposite was confirmed using several characterization techniques, including X-ray diffractometer (XRD), Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), total organic carbon analysis (TOC), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), transmission electron microscopy (TEM), atomic force microscopy (AFM) and and X-ray photoelectron spectroscopy (XPS). The adsorption performance of the synthesized nanocomposite adsorbents was evaluated under optimized conditions (C0 = 160 mg/L, pH = 7, mixing time = 120 min, adsorbent = 10 mg, stirring = 300 rpm, volume = 10 mL), with pristine GO and GO@Thy:LevA (1:3) nanocomposite exhibiting remarkable adsorption capacities of 63.50 mg/g and 91.51 mg/g, respectively. Kinetic studies showed that the adsorption process followed a pseudo-first-order model, whereas thermodynamic analysis confirmed the endothermic and spontaneous nature of the adsorption process. Advanced statistical physics models, particularly the monolayer model with two energies (M2), have provided new insights into the adsorption mechanism at the molecular level. Density functional theory (DFT) calculations and conductor-like screening model for real solvents (COSMO-RS) studies further elucidated the adsorbent-adsorbate interactions, with theoretical predictions corroborating experimental findings. The reusability of the adsorbents over five cycles was demonstrated, highlighting their potential for practical applications.

Customized Copolymer composite coatings for carbon capture Environments: Corrosion inhibition and CO2 barrier Synergy

Global warming is attributed to excessive emissions of greenhouse gases, which are being addressed through the deployment of carbon capture technologies aimed at mitigating climate change. However, this approach faces significant challenges, as high concentrations of CO2 pose a huge risk of corrosion, compromising integrity. The active inhibitor polyfluoroaniline grown on the surface of graphene (Gr-PFAN) is encapsulated in epoxy novolac (EN) coating. And highly reactive nitrogen-containing poly(p-phenylenediamine-fluoroaniline) (Gr-PPFAN) was synthesized by changing the polymerization monomer. For the first time, primary amine nitrogen-containing active sites are discussed in CO2 shielding material. The gas transmission rate (GTR) test showed that the GTR of the composite film containing Gr-PPFAN was 3.7 times higher than that of Gr-PFAN. And the presence of highly reactive amines in the polymer mass transfer behavior was calculated by molecular simulation. Therefore, the PPFAN coating is a serious failure in H2O-CO2 environment. The introduction of the low content of active sites in Gr-PFAN into the epoxy resin matrix resulted in significant enhancement of the H2O, H2O-CO2 and H+ corrosion resistance. The small amount of active amine not only enhances the phase interface between the resin and the flake filler, but also facilitates the formation of a protective layer on the metal surface. Experimental results demonstrated that Gr-PFAN/EN exhibited the highest |Z|0.01 Hz value (3.5 × 1011 O × cm2) after 90 days of immersion in 3.5 wt% NaCl solution and 1.5 × 1011 O × cm2 for 30 days in the carbon capture environment. Furthermore, it makes Gr-PFAN/EN a promising candidate for practical applications in CO2 capture projects. The findings provide a scientific basis for the development of efficient anti-corrosion coatings suitable for carbon capture technologies.

3D composite SERS substrates with COF spaced Au nanoparticles for enrichment and selective sensitive detection

The excellent performance of surface-enhanced Raman spectroscopy (SERS) is closely related to the intensity, density and uniformity of hotspots. In this study, we introduce a PET/Au NPs@COF Raman substrate featuring three-dimensional hotspots. The spacing between each layer of gold nanoparticles (NPs) is precisely controlled by adjusting the thickness of the COF via the interfacial synthesis technique, causing the strong coupling between gold particles across the layers. The porosity of the COF enables the substrate to adsorb numerous analyte molecules into the large-area uniform hotspots. Through simulations and adsorption detection on the substrate, Raman testing further demonstrated that the substrate with double-layer Au NPs@COF exhibited the most favorable SERS performance. Additionally, the substrate allows for selective detection based on the particle size of the target molecule. The flexibility of the substrate enables it to conform to irregular surfaces, effectively capturing analytes from a variety of real samples.

Application of mass spectrometry for the advancement of PROTACs

The advent of targeted protein degradation technologies, particularly Proteolysis-Targeting Chimeras (PROTACs), enable the selective elimination of target proteins and open up new avenues for the treatment of various diseases. This review delves into the pivotal role of mass spectrometry (MS) in the advancement of PROTACs. MS-based methodologies serve as invaluable tools for identifying PROTAC targets, validating their efficacy, and elucidating ubiquitination sites and protein degradation dynamics. These insights profoundly enrich our comprehension of the mechanisms of action and facilitate the rational design of PROTACs. Furthermore, this review discusses the role of MS in the structural analysis of proteins and the formation of ternary complexes crucial for the activity of PROTACs. The synergy between MS and PROTAC technology holds the promise of groundbreaking advancements in drug discovery by deepening our understanding of the underlying mechanisms that govern PROTAC drug action, thereby promoting the development of innovative strategies for disease treatment.

Fluorescent sensor array for rapid bacterial identification using antimicrobial peptide-functionalized gold nanoclusters and machine learning

Bacterial infectious diseases pose significant challenges to public health, emphasizing the need for rapid and accurate diagnostic tools. Here, we introduced a multichannel fluorescent sensor array based on antimicrobial peptide-functionalized gold nanoclusters (AMP-AuNCs) designed for precise bacterial identification. By utilizing the unique electrostatic and hydrophobic properties of three AMP-AuNCs, this sensor array generated distinct fluorescence patterns upon binding to different bacterial species. Machine learning algorithms, including Principal Component Analysis (PCA), Hierarchical Clustering Analysis (HCA), and Linear Discriminant Analysis (LDA), were employed to analyze fluorescence fingerprint patterns and identify bacterial strains with high accuracy. The sensor array achieved 100 % accuracy in identifying six common bacterial species and demonstrated an 86.7 % accuracy in classifying clinical Escherichia coli isolates from urinary tract infections. This AMP-AuNC-based sensor array offers a promising approach for rapid and precise bacterial diagnostics, with potential applications in clinical settings for combating antibiotic resistance.