External stimuli-responsive drug delivery to the posterior segment of the eye

Posterior segment eye diseases represent the leading causes of vision impairment and blindness globally. Current therapies still have notable drawbacks, including the need for frequent invasive injections and the associated risks of severe ocular complications. Recently, the utility of external stimuli, such as light, ultrasound, magnetic field, and electric field, has been noted as a promising strategy to enhance drug delivery to the posterior segment of the eye. In this review, we briefly summarize the main physiological barriers against ocular drug delivery, focusing primarily on the recent advancements that utilize external stimuli to improve treatment outcomes for posterior segment eye diseases. The advantages of these external stimuli-responsive drug delivery strategies are discussed, with illustrative examples highlighting improved tissue penetration, enhanced control over drug release, and targeted drug delivery to ocular lesions through minimally invasive routes. Finally, we discuss the challenges and future perspectives in the translational research of external stimuli-responsive drug delivery platforms, aiming to bridge existing gaps toward clinical use.

Electrochemical biosensing in oncology: a review advancements and prospects for cancer diagnosis

Early and precise diagnosis of cancer is pivotal for effective therapeutic intervention. Traditional diagnostic methods, despite their reliability, often face limitations such as invasiveness, high costs, labor-intensive procedures, extended processing times, and reduced sensitivity for early-stage detection. Electrochemical biosensing is a revolutionary method that provides rapid, cost-effective, and highly sensitive detection of cancer biomarkers. This review discusses the use of electrochemical detection in biosensors to provide real-time insights into disease-specific molecular interactions, focusing on target recognition and signal generation mechanisms. Furthermore, the superior efficacy of electrochemical biosensors compared to conventional techniques is explored, particularly in their ability to detect cancer biomarkers with enhanced specificity and sensitivity. Advancements in electrode materials and nanostructured designs, integrating nanotechnology, microfluidics, and artificial intelligence, have the potential to overcome biological interferences and scale for clinical use. Research and innovation in oncology diagnostics hold potential for personalized medicine, despite challenges in commercial viability and real-world application.

Quantifying antibody binding: techniques and therapeutic implications

The binding kinetics of an antibody for its target antigen represent key determinants of its biological function and success as a novel biotherapeutic. Defining these interactions and kinetics is critical for understanding the pharmacological and pharmacodynamic profiles of antibodies in therapeutic applications, with line of sight to clinical translation. In this review, we discuss the latest developments in approaches to measure and modulate antibody-antigen interactions, including antibody engineering, novel antibody formats, current, and emerging technologies for measuring antibody-antigen binding interactions, and emerging perspectives within the field. We also explore how emerging computational methods are set to become powerful tools for modeling antibody-binding interactions under physiologically relevant conditions. Finally, we consider the therapeutic implications of modulating target engagement in terms of pharmacodynamics and pharmacokinetics.

The role of cisplatin in modulating the tumor immune microenvironment and its combination therapy strategies: a new approach to enhance anti-tumor efficacy

Cisplatin is a platinum-based drug that is frequently used to treat multiple tumors. The anti-tumor effect of cisplatin is closely related to the tumor immune microenvironment (TIME), which includes several immune cell types, such as the tumor-associated macrophages (TAMs), cytotoxic T-lymphocytes (CTLs), dendritic cells (DCs), myeloid-derived suppressor cells (MDSCs), regulatory T cells (Tregs), and natural killer (NK) cells. The interaction between these immune cells can promote tumor survival and chemoresistance, and decrease the efficacy of cisplatin monotherapy. Therefore, various combination treatment strategies have been devised to enhance patient responsiveness to cisplatin therapy. Cisplatin can augment anti-tumor immune responses in combination with immune checkpoint blockers (such as PD-1/PD-L1 or CTLA4 inhibitors), lipid metabolism disruptors (like FASN inhibitors and SCD inhibitors) and nanoparticles (NPs), resulting in better outcomes. Exploring the interaction between cisplatin and the TIME will help identify potential therapeutic targets for improving the treatment outcomes in cancer patients.

Exploring the efficacy and constraints of platinum nanoparticles as adjuvant therapy in silicosis management

Silicosis represents a formidable occupational lung pathology precipitated by the pulmonary assimilation of respirable crystalline silica particulates. This condition engenders a cascade of cellular oxidative stress via the activation of bioavailable silica, culminating in the generation of reactive oxygen species (ROS). Such oxidative mechanisms lead to irrevocable pulmonary impairment. Contemporary scholarly examinations have underscored the substantial antioxidative efficacy of platinum nanoparticles (PtNPs), postulating their utility as an adjunct therapeutic modality in silicosis management. The physicochemical interaction between PtNPs and silica demonstrates a propensity for adsorption, thereby facilitating the amelioration and subsequent pulmonary clearance of silica aggregates. In addition to their detoxifying attributes, PtNPs exhibit pronounced anti-inflammatory and antioxidative activities, which can neutralize ROS and inhibit macrophage-mediated inflammatory processes. Such attributes are instrumental in attenuating inflammatory responses and forestalling subsequent lung tissue damage. This discourse delineates the interplay between ROS and PtNPs, the pathogenesis of silicosis and its progression to pulmonary fibrosis, and critically evaluates the potential adjunct role of PtNPs in the therapeutic landscape of silicosis, alongside a contemplation of the inherent limitations associated with PtNPs application in this context.

Leveraging deep learning for epigenetic protein prediction: a novel approach for early lung cancer diagnosis and drug discovery

Epigenetic protein (EP) plays a crucial role in influencing disease development, controlling gene expression, and shaping cell identity. They hold potential as targets for future therapies, and studying their mechanisms can lead to improved diagnosis and treatment strategies for various diseases. Anticipating EP is imperative, yet conventional experimental approaches for prediction prove time-intensive and expensive. This work constructed CNN-BiLSTM, computational method for identification of EP prediction. Utilizing primary sequences, two datasets were constructed, and an amphiphilic pseudo amino acid, group dipeptide composition and group amino acid composition were devised to extract numerical features. Model training incorporated a suite of deep learning architectures, including BiLSTM, GRU, and CNN. Notably, an ensemble model combining CNN and BiLSTM, trained using AmpPseAAC features, demonstrated superior performance across both training and testing datasets compared to other predictors. This research contributes to the ongoing efforts to revolutionize therapeutic approaches by facilitating the identification of novel drug targets and improving disease treatment outcomes.

Alpha-linolenic acid-mediated epigenetic reprogramming of cervical cancer cell lines

Cervical cancer, the fourth most common cancer globally and the second most prevalent cancer among women in India, is primarily caused by Human Papilloma Virus (HPV). The association of diet with cancer etiology and prevention has been well established and nutrition has been shown to regulate cancer through modulation of epigenetic markers. Dietary fatty acids, especially omega-3, reduce the risk of cancer by preventing or reversing the progression through a variety of cellular targets, including epigenetic regulation. In this work, we have evaluated the potential of ALA (α linolenic acid), an ω-3 fatty acid, to regulate cervical cancer through epigenetic mechanisms. The effect of ALA was evaluated on the regulation of histone deacetylases1, DNA methyltransferases 1, and 3b, and global DNA methylation by ELISA. RT-PCR was utilized to assess the expression of tumor regulatory genes (hTERT, DAPK, RARβ, and CDH1) and their promoter methylation in HeLa (HPV18-positive), SiHa (HPV16-positive) and C33a (HPV-negative) cervical cancer cell lines. ALA increased DNA demethylase, HMTs, and HATs while decreasing global DNA methylation, DNMT, HDMs, and HDACs mRNA expression/activity in all cervical cancer cell lines. ALA downregulated hTERT oncogene while upregulating the mRNA expression of TSGs (Tumor Suppressor Genes) CDH1, RARβ, and DAPK in all the cell lines. ALA reduced methylation in the 5' CpG island of CDH1, RARβ, and DAPK1 promoters and reduced global DNA methylation in cervical cancer cell lines. These results suggest that ALA regulates the growth of cervical cancer cells by targeting epigenetic markers, shedding light on its potential therapeutic role in cervical cancer management.

Rational design of dual-state emission fluorophores for sensing nitro explosives by using sulfone unit as an electron acceptor in D-A system

Dual-state emission (DSE) fluorescent molecules have become the preferred type in designing sensing fluorescent molecules due to the virtue of their bright emission in both solid and liquid states. In this study, five D-A molecules were successfully designed and synthesized according to the design concept that structural modification of D-A molecules can lead to DSE molecules. Among them, the balance between the electron donor with a strong electron donation capacity and the twisted conformation in the whole molecule makes the compounds 3c-3e DSE molecules with excellent optical performances, showing significant solvatochromic effects and large Stoke shifts. In addition, the feasibility of the sulfone unit as an electron acceptor in the D-A structure is also verified, extending the application of sulfone group in the field of fluorescence. Interestingly, the fluorescence of 3c can exhibit sensitive and selective quenching of nitro aromatic compounds (NACs) under the synergistic mechanism of fluorescence resonance energy transfer (FRET) and photoinduced electron transfer (PET), with LOD as low as 10-8 M and KSV as high as 104 M-1. Furthermore, the selective, efficient, and sensitive detection of NACs by DSE fluorescent molecule 3c in real aqueous samples and loaded on test strips has demonstrated the potential of its practical applications.

Ratiometric fluorescent probe for triphosgene detection and its application in electrospun fluorescent fibers

Triphosgene poses a potentially great threat to human health and safety. Therefore, it is of great significance to develop an effective method to realize the inexpensive, on-site, convenient, and rapid detection of triphosgene. Herein, based on the excited-state intramolecular proton transfer mechanism, a new fluorescent probe DPIM was designed and synthesized, which realized the rapid ratiometric identification and detection of triphosgene for the first time. Its limit of detection for triphosgene was 3.54 × 10-8 M, and it had a large Stokes shift of 198 nm. Its recognition mechanism was comprehensively analyzed. A smartphone detection platform and probe-loaded test paper were prepared to realize the inexpensive, on-site, and convenient detection of triphosgene. DPIM effectively enabled the ratiometric fluorescence "turn-on" for detecting residual triphosgene in the sand, showing its application practicality. Most importantly, the probe was incorporated into nanofibers and successfully used to monitor gaseous triphosgene with high specificity, showing its excellent application potential. This study provides a promising analytical tool for the rapid quantitative detection of triphosgene in solution and gaseous phases.

A smart photosensitive fluorescent probe for sensing Co2+ in extremely alkaline aqueous solution

A novel pH-, viscosity-, and photo-sensitive polymorphic fluorescence probe NHP for sensing Co2+ has been developed. The hydrazone-based NHP can be synthesized by only one step of reflux reaction and purified by washing with poor solvents. Three single crystals of NHP-1, NHP-2, and NHP-3 with different conformations were resolved. As a photo acid generator (PAG), the hydrogen atom on the imino group of the probe NHP can be shed with 365 nm ultraviolet (UV) light illumination or in alkaline conditions. Due to the above two conditions, the negatively charged ligand obtained after dehydrogenation of NHP can accelerate its chelation with Co2+. When irradiated with 365 nm UV light, the product (NHP2-Co2+ (I)) of NHP chelating with Co2+ appears yellowish in aqueous solution. In a strong alkali aqueous solution, the chelate product (NHP2-Co2+ (II)) of NHP and Co2+ showed bright blue-green fluorescence. The formed divalent Co(II) complex NHP2-Co2+ can be oxidized to trivalent Co(III) complex NHP3-Co3+, as confirmed by the resolution of single crystals of NHP3-Co3+.

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.

Molybdoenzymes-emulating bio-heterojunction hydrogel with rapid disinfection and macrophage reprogramming for wound regeneration

Developing hydrogel dressings with the capabilities to accommodate irregular wounds and provide a cascade disinfective-regenerative microenvironment for wound repair is of great importance to combating pathogenic bacteria-infected wounds but remains an ongoing challenge. To address the conundrum, we devise a molybdoenzymes-emulating bio-heterojunction (M-bioHJ) doped double network (DN) hydrogel dressing for bacterial-infected wound healing. The near-infrared (NIR) photothermal effect of the M-bioHJ facilitates the exchange of multiple dynamic crosslinking sites in the hydrogel, endowing the hydrogel with photo-remote reprocessing capabilities to completely accommodate the encountered irregular wounds and ultimately accomplish the admirable therapeutic effect. Meanwhile, the introduced M-bioHJ shows NIR light-enhanced photodynamic activity to induce a massive engendering of reactive oxygen species (ROS), allowing rapid sterilization without reliance on exogenous hydrogen peroxide. Furthermore, the Mo ions released from the M-bioHJ-encapsulated hydrogel can play a crucial role in reprogramming the macrophage phenotype and determining tissue regeneration. Both in vitro and in vivo evidences authenticate the accelerated healing potential of infected wounds through the synergistic effects of photo-reprocessing, disinfection, and macrophage-reprogramming facilitated by the hydrogel. These findings highlight the promising application prospects of such neoteric M-bioHJ-encapsulated hydrogel dressings for wound disinfection and tissue regeneration.

A PEG-based strategy to improve detection of clinical microRNA 155 by bio-Field Effect Transistor in high ionic strength environment

microRNAs are small oligonucleotides involved in post-transcriptional gene regulation whose alteration is found in several diseases, including cancer, and therefore their detection is crucial for diagnosis, prognosis, and treatment purposes. Field-Effect Transistor-based biosensors (bioFETs) represent a promising technology for the clinical detection of microRNAs. However, one of the main challenges associated with this technology is the Debye screening, becoming significant at the high ionic strengths required for effective hybridization. We aimed at detecting oncogenic microRNA-155 by using a bioFET system using as capture element a complementary RNA probe (antimiR-155) combined with the introduction of PEG molecules (20 kDa, PEG20), at an ionic strength of 300 mM. We optimized the co-immobilization ratio between antimiR-155 and PEG20 and assessed its impact on the interactions between the oligonucleotides. The kinetics can be well described by the Langmuir-Freundlich isotherm with an affinity constant within the range typical of nucleic acid interactions. The introduction of PEG20 significantly enhanced the detection sensitivity of miR-155 by reaching a level of less than 200 pM, together with excellent discrimination against other clinically relevant microRNAs. Our findings demonstrate that the incorporation of PEG20 constitutes an effective strategy to mitigate the Debye screening effects and facilitates bioFET-based clinical applications at physiological ionic strengths.

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.

Band gap regulation of MIL-101(Fe) via pyrazine-based ligands substitution for enhanced visible-light adsorption and its photo-Fenton-like application

Regulating the photo-response region of iron metal-organic frameworks (Fe-MOFs) is a viable strategy for enhancing their practical application in the visible-light driven photo-Fenton-like process. This study developed a novel pyrazine-based Fe-MOFs (MIL-101(Fe)-Pz) by substituting the 1,4-dicarboxybenzene acid ligands in typical MIL-101(Fe) with 2,5-pyrazinedicarboxylic acid (PzDC), in which sodium acetate was used as coordinative modulator to control the crystal size (2-3 µm). The incorporation of Fe-pyridine N coordination structures originated from PzDC ligands gave MIL-101(Fe)-Pz narrowed band gap (1.45 eV) than MIL-101(Fe) (2.54 eV) resulting in improved visible-light adsorption capacity (λ > 420 nm), and also increased the proportion of Fe(II) in the Fe-clusters. Thus MIL-101(Fe)-Pz exhibited a synergistic enhanced photo-Fenton-like catalytic performance under visible-light irradiation. The MIL-101(Fe)-Pz/H2O2/Vis system could degrade 99% of sulfamethoxazole within 30 min, which was 10-fold faster than that of the pristine MIL-101(Fe), it also effectively removed other organic micropollutants with high durability and stability. Mechanistic analysis revealed that the PzDC ligands substitution decreased the band gap of MIL-101(Fe), giving MIL-101(Fe)-Pz appropriate band structure (-0.40∼1.05 V vs. NHE) which can cover several light-driven process for the generation of reactive oxygen species, including Fe(III) reduction and H2O2 activation for accelerating •OH generation, as well as oxygen reduction reaction for generating H2O2, O2•- and 1O2. This study highlights the role of pyridine-N containing ligands in regulating the band structure of Fe-MOFs, providing valuable guidance for the design of Fe-MOFs photocatalysts.

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.

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.

Development of an electroconductive Heart-on-a-chip model to investigate cellular and molecular response of human cardiac tissue to gold nanomaterials

To date, various strategies have been developed to construct biomimetic and functional in vitro cardiac tissue models utilizing human induced pluripotent stem cells (hiPSCs). Among these approaches, microfluidic-based Heart-on-a-chip (HOC) models are promising, as they enable the engineering of miniaturized, physiologically relevant in vitro cardiac tissues with precise control over cellular constituents and tissue architecture. Despite significant advancements, previously reported HOC models often lack the electroconductivity features of the native human myocardium. In this study, we developed a 3D electroconductive HOC (referred to as eHOC) model through the co-culture of isogenic hiPSC-derived cardiomyocytes (hiCMs) and cardiac fibroblasts (hiCFs), embedded within an electroconductive hydrogel scaffold in a microfluidic-based chip system. Functional and gene expression analyses demonstrated that, compared to non-conductive HOC, the eHOC model exhibited enhanced contractile functionality, improved calcium transients, and increased expression of structural and calcium handling genes. The eHOC model was further leveraged to investigate the underlying electroconduction-induced pathway(s) associated with cardiac tissue development through single-cell RNA sequencing (scRNA-seq). Notably, scRNA-seq analyses revealed a significant downregulation of a set of cardiac genes, associated with the fetal stage of heart development, as well as upregulation of sarcomere- and conduction-related genes within the eHOC model. Additionally, upregulation of the cardiac muscle contraction and motor protein pathways were observed in the eHOC model, consistent with enhanced contractile functionality of the engineered cardiac tissues. Comparison of scRNA-seq data from the 3D eHOC model with published datasets of adult human hearts demonstrated a similar expression pattern of fetal- and adult-like cardiac genes. Overall, this study provides a unique eHOC model with improved biomimcry and organotypic features, which could be potentially used for drug testing and discovery, as well as disease modeling applications.

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.

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 new HBT-quinolinium platform for optical detection of biogenic amines and its application in food quality monitoring

Biogenic amines (BAs) are critical biomolecules that play key roles in physiological processes and serve as important indicators in food safety, clinical diagnostics, and environmental monitoring. Therefore, sensitive, selective, and rapid tools are required for BA detection. This study explores the synthesis and applications of a new fluorescent probe (DBQ) for detecting BAs, focusing on their fluorescence response mechanisms. DBQ offers a promising alternative due to its high selectivity, sharp color change, low detection limit (0.057 μM for cadaverine), long lifetime (τ ≈ 2.40 ns), rapid response (15 min), low cytotoxicity (over 90 % cell viability in the presence of 10.0 μM of DBQ) and favorable photophysical properties, including large Stokes shift (213 nm in CHCl3). In addition, DBQ displays solvent-dependent intramolecular charge transfer (ICT), resulting in solvatochromism. The developed smartphone sensing system was applied to the detection of BAs. The developed sensing test kit responds quickly to the presence of volatile biogenic amines, with notable visible response and high selectivity. In on-site analysis, we were able to successfully use these test strips for non-destructive evaluation of chicken and cheese freshness with the use of a smartphone. Therefore, the current study will contribute to improving food safety and reduce food loss and waste by developing new bioanalytical technologies that offer chemical information about the composition of food, which is extremely valuable for enhancing traceability and extending food shelf life.

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.

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.

Multi-target analysis of synthetic phenolic compounds in human blood

Synthetic phenolic compounds are widely used in plastics and personal care products, leading to potential high human exposure. This study aimed to develop two multi-target analytical methods to quantify phenolic compounds in human serum, including free and conjugated synthetic phenolic antioxidants (SPAs), bisphenols, parabens, and UV filters. The two methods were applied to 30 human serum samples from young adults (15 females and 15 males) living in Stockholm, Sweden. An average recovery of 73 % (range 36-125 %) and good reproducibility (RSD <30 %) were established for 37 target analytes, and another four analytes were semi-quantified. Twenty-one target analytes were found above quantification levels. Notable, five SPAs, namely 2,2'-methylenebis(4-methyl-6-tert-butylphenol) (AO2246), 4,4'-methylenebis(2,6-di-tert-butylphenol) (AO4426), 4-tert octylphenol (4-tOP), butylade hydroxyanisole (BHA), butylated hydroxytoluene (BHT) were quantified in >93 % of samples, and with median concentrations between 1.4 (BHA) and 520 ng/g (AO2246). Other compounds quantified in the samples were bisphenol B (quantification frequency 57 %) and methylparaben (quantification frequency 87 %), with median concentrations of 0.38 and 1.6 ng/g respectively. Additionally, two features were semi-quantified using suspect screening: Fenozan (an SPA metabolite, 3-(3,5-Di-tert-butyl-4-hydroxyphenyl)propionic acid) and benzophenone-4 (a UV filter, 5-benzoyl-4-hydroxy-2-methoxybenzenesulfonic acid). To the best of our knowledge, this is the first time AO4426, 3,5-di-tert-butyl-4-hydroxybenzoic acid (BHT-COOH), 2-tert-butylbenzene-1,4-diol (TBHQ), bisphenol B, and Fenozan have been found in human blood. The finding of SPAs in human blood indicates high human exposure and needs further investigation.

A new perspective on antimicrobial therapeutic drug monitoring: Surface-enhanced Raman spectroscopy

Therapeutic drug monitoring (TDM) enables the personalization of treatment regimens, enhancing efficacy in combating infectious diseases while minimizing toxicity risks and reducing the potential for pathogenic resistance. However, existing TDM techniques still present certain limitations. Chromatographic analysis involves a prolonged detection period, which hampers its capacity for rapid multi-sample analysis. Immunoassay is constrained by poor specificity and stability, as well as a restricted range of detectable drugs. Surface-enhanced Raman spectroscopy (SERS) amplifies the Raman signals of target molecules via the local electromagnetic field and charge transfer effects on the surface of plasmonic materials, offering many significant advantages including high sensitivity, rapid detection, minimal sample requirements, and the ability to provide molecular fingerprints. SERS biosensing has demonstrated considerable potential in the field of blood drug concentration monitoring. This paper comprehensively reviews the research on the application of SERS in the TDM of antimicrobial agents. Beginning with the clinical practice of antimicrobial TDM, this review systematically introduces the principles of SERS techniques, the enhancement substrates, and the commonly used data processing methods including machine learning. It then provides a detailed discussion of the application of SERS in the TDM of various types of antimicrobials. Finally, it summarizes four major challenges currently faced by SERS techniques in antimicrobial TDM-namely protein corona effects, matrix interferences, substrate heterogeneity, and quantification reproducibility-and proposes potential future directions. This paper aims to offer new strategies and perspectives for the TDM and personalized dosage of antimicrobial agents.

A new β-amylase detection strategy based on encapsulated enzyme in magnetic layered double hydroxide with high sensitivity and simplified workflow

β-Amylase (BMY) is a linchpin in food production and the pharmaceutical industry because the enzyme efficiently controls the ratio of diverse saccharides in fermentation and the manufacture of high-quality maltose. However, existing BMY detection tactics suffer from inadequate selectivity/sensitivity and cumbersome operation and do not meet the needs of precise quantification. Consequently, there is an urgent need to develop an ultrasensitive sensing platform to achieve precise BMY analysis with a low detection limit and simpler workflow. In this work, we establish an encapsulated-enzyme-based BMY biosensing platform in which α-glucosidase is embedded in magnetic layered double hydroxide using a self-sacrificing template. The encapsulated enzyme has increased activity, robustness, and recyclability and was utilized for BMY detection via a cascade chromatic process. We found a detection limit for the quantification of BMY activity of 2.67 U/L with a broad range (5-400 U/L), fast response speed (10 min), and satisfactory specificity. We applied the biosensing platform to liquor starters to verify the capability of the assay in complicated fermentation samples. The proposed platform holds great promise as an efficient and simple method for enzymatic bioactivity monitoring in food manufacturing, biopharmaceutical processing, and clinical laboratory tests.

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.

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.

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.

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.

A two-pronged G-quadruplex construction strategy enables the development of a two-in-one aptasensor for β-lactoglobulin

Food allergies are a global concern since they threaten human health and are challenging to treat. Avoiding allergen exposure is an effective measure for vulnerable individuals, requiring reliable and simple allergen detection techniques. This can be achieved by integrating aptamer and G-quadruplex (G4) components into a sequence as a smart nucleic acid sensing nanodevice. The challenge lies in the functional structure formation of these components due to the lengthy integrated sequence and its conformational complexities. This study proposes a two-pronged strategy, encompassing both the nucleic acid sequence level and spatial structure levels, to construct a functional parallel G4 for an aptamer-loop-G4 integrated sequence, thereby enabling colorimetric detection of β-lactoglobulin (β-LG). Specifically, through comprehensive tailoring, interfering structures are excluded, and the integrated sequence is modified to adopt an appropriate G4 conformation to enhance signaling efficiency. Additionally, the topologically guided combined use of Mg2+ and K+ ions coordinates the conformational folding of the aptamer and G4 components, ensuring the recognition capacity of the aptamer. Finally, a β-LG aptasensor is established that presents advantages, such as cost-efficiency, simple operation, 35-min rapid detection, excellent specificity, and sensitivity for a linear range of nearly four orders of magnitude, meeting point-of-care testing (POCT) requirements.

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.

Label-free turn-on electrochemiluminescence assay of β-glucuronidase at single-electrode

Electrochemiluminescence (ECL) has achieved significant commercial success over the past few decades across various fields, particularly in the healthcare industry. The measurement scheme oftentimes involves target recognition elements (e.g. catching antibodies) labeled with a suitable ECL luminophore (e.g. tris(2,2'-bipyridine)ruthenium(II))). While this approach realizes the ultrasensitive detection of various biomarkers, it is somewhat complicated strategy for certain targets such as enzymes. In this study, β-glucuronidase (B-GLU), a promising biomarker and a common water/foodstuff safety indicator, was quantified by measuring the ECL signal of fluorescent product generated from non-fluorescent substrate by the B-GLU enzyme. To this end, hot electron-induced ECL of three luminophores (fluorescein, 4-methylumbelliferyl and resorufin) that are used as building blocks to synthesize various commercially available non-fluorescent substrates was compared for the first time. To increase the appeal and practicality of this approach, the common multi-well assay format was adapted to the present type ECL by carrying out the ECL reactions at single carbon black/polystyrene electrode. In this electrochemical setup, multiple cells were fabricated on the surface of a poorly conducting substrate by attaching Teflon tape with multiple holes to the substrates surface. Sample throughput time decreases considerable as target, blank and sample signals can be simultaneously obtained from the electrochemical cells when voltage is applied across the single electrode. The detection limit for B-GLU after 2 h of incubation was 0.07 U L-1 when 4-methylumbelliferyl-β-D-glucuronide was used as the fluorogenic substrate and Br- was used as the co-reactant. B-GLU recovery rates from diluted saliva with the present ECL approach were adequate (93-103 %) and similar to those obtained with the fluorescence technique.

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.

Flexible and wearable electrochemical sensors for health and safety monitoring

Environmental safety monitoring is a crucial process that involves continuous and systematic observation and analysis of various pollutants in the environment to ensure its quality and safety. This monitoring encompasses a wide range of areas, including physical indicator monitoring (pertaining to parameters such as temperature, humidity, and wind speed), chemical indicator monitoring (focused on detecting harmful substances in environmental media such as air, water, and soil), and ecosystem monitoring (including biodiversity assessments and judgments on the health status of ecosystems). This review delves deeply into the significant advancements achieved in the field of flexible and wearable electrochemical sensors (FWESs) over the past fifteen years (from 2010 to 2024). It emphasizes the broad application of these sensors in health and environmental safety monitoring, with health monitoring primarily focusing on exhaled breath and sweat, and environmental monitoring covering temperature, humidity, and pollutants in air and water. By seamlessly integrating electrochemical principles, advanced sensor manufacturing technologies, and sensor functionalization, FWESs have opened up new avenues for non-invasive real-time monitoring of human health and environmental safety. This review highlights key developments in sensor structures, including flexible substrates, printed electrodes, and active materials. It also underscores the remarkable progress made in healthcare and environmental monitoring through the utilization of FWES. Despite these promising advancements, this emerging field still faces numerous challenges, such as improving sensor accuracy, enhancing durability, and reducing costs. The review concludes by discussing the future directions in this field, including ongoing research efforts aimed at overcoming these challenges and expanding the applications of FWESs in various sectors.

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.

A novel ratiometric electrochemical assay for detection of formaldehyde in real food samples

This study developed a novel ratiometric electrochemical sensor for detecting formaldehyde content in food. For the first time, we innovatively utilized 4-amino-3-hydrazino-5-mercapto-1,2,4-triazole (AHMT), a traditional colorimetric probe that specifically reacts with formaldehyde, as an electrochemical probe to construct the electrochemical assay. The reaction product of AHMT with formaldehyde exhibits different redox potentials from AHMT, thereby enabling ratiometric detection of formaldehyde. We systematically investigated the electrochemical behavior of AHMT and its reaction product with formaldehyde. Under optimized conditions, this novel ratiometric electrochemical assay demonstrated high sensitivity and selectivity for formaldehyde, with a response linear range of 0.1-20 μM and a detection limit of 21 nM. Additionally, the sensor was successfully applied to detect formaldehyde in various mushrooms and fish, with measured concentrations of 1.34 μg g-1 in shimeji mushrooms, 0.80 μg g-1 in oyster mushrooms, 1.41 μg g-1 in enoki mushrooms, and 1.12 μg g-1 in king oyster mushrooms. For seafood, concentrations of 2.45 μg g-1 in cuttlefish and 0.83 μg∙g-1 in cutlassfish fish were detected. These results were validated against the standard method, underscoring the sensor's potential and reliability for practical applications. This study is anticipated to offer valuable insights for the development of innovative electrochemical sensors for food analysis.

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.

Hydroxyl and phenyl co-modified carbon nitride-based ratiometric fluorescent nanoprobe for monitoring mitochondrial pH in live cells and differentiating cell death

Monitoring mitochondrial pH and differentiating live and dead cells are crucial for diagnosing cell status. However, most fluorescent probes suffer from limitations such as high cytotoxicity, photobleaching, unreliability, and an inability to differentiate cell death caused by different inducers. Herein, a ratiometric fluorescent nanoprobe was developed by assembling pH-sensitive hydroxyl- and phenyl-co-modified carbon nitride (HPCN) with pH-insensitive Rhodamine B (RB). HPCN was prepared via thermal condensation of phenylguanidine carbonate using NaOH as the melt. The hydroxyl group modification endowed HPCN with improved water solubility and pH-sensitive characteristics, while the phenyl group modification facilitated mitochondrial targeting and DNA staining via hydrophobic interactions. Based on the fluorescence resonance energy transfer (FRET) from HPCN to RB, the nanoprobe exhibited a linear response in the relative fluorescence intensities at 500 nm and 584 nm over a pH range of 4.5-8.5. Benefiting from its low cytotoxicity, excellent reversibility, and outstanding photostability, the nanoprobe was capable of monitoring mitochondrial pH changes in live cells and differentiating live and dead cells, apoptosis and necrosis, and necrosis induced by different agents, regardless of cell type. This work provides a reliable method for diagnosing cell status and cell death induced by various inducers.

Ni(II) complexes of His2 peptides as multi-responsive electrochemical probes for anion sensing

Peptides possessing a histidine residue at the second position (His2) exhibit distinctive coordination properties, effectively binding transition metal cations. The resulting complexes, with labile binding sites, offer advantageous features as potential molecular receptors. In this work, a His2 peptide library was designed to select a sequence that, upon binding Ni(II) ions, would exhibit the most promising properties for anion sensing. Electrochemical techniques were used to characterize the redox properties of the studied Ni(II)-His2 peptide complexes. Subsequently, voltammetric responses of the complexes in the presence of various biologically relevant anions (chlorides, sulfates, acetates, lactates and phosphates) were collected and analyzed using Principal Component Analysis, providing effective anion discrimination based on electrochemical fingerprints. Finally, a simple methodology was proposed to differentiate varying lactate and phosphate concentrations in complex, multi-ion samples, simulating physiological and pathological blood plasma conditions. The results confirm the high application potential of the proposed class of molecular receptors and provide insights into novel anion-sensing strategies utilizing metal-peptide complexes as multi-responsive electrochemical probes.

A multifunctional biosensor for linked monitoring of inflammation indicators in hypertension drug evaluation and companion diagnostics

Hypertension, often called the "silent killer", is a prevalent chronic disease closely linked to inflammation. However, most current methods monitor only single indicator, providing a limited view of inflammation in hypertension progression. To address this, we developed a multifunctional biosensor featuring a dual target linked monitoring (DTLM) Probe for the simultaneous detection of IL-6 and CRP, two key inflammatory markers in hypertension progression. The DTLM Probe, based on NH2-UiO-66@AuNPs with mutually non-interfering signal chains, was optimized for high performance in tracking both indicators simultaneously. The dual outputs operate independently, enabling IL-6 and CRP to be detected together or individually within a single sample injection. Under optimized conditions, the biosensor demonstrated excellent specificity and sensitivity, with detection limits of 355 fg/mL for IL-6 and 367 fg/mL for CRP. Applied to a rat model, the biosensor effectively explored the anti-inflammatory effects of Qishenyiqi, a traditional Chinese medicine, assessing its efficacy in reducing hypertensive heart damage. Additionally, it distinguished IL-6 and CRP levels between healthy and hypertensive individuals, capturing subtle changes after treatments. This ensured targeted anti-inflammatory therapies for patients who would benefit most. This biosensor provides a powerful and versatile platform for dual markers tracking, supporting both drug evaluation and companion diagnostics for tailor treatments in hypertension management.

Cysteine-assisted synthesis of copper nanoclusters for construction of FRET-based ratiometric sensor for visual detection of alkaline phosphatase

Abnormal alkaline phosphatase (ALP) levels in the human body are closely associated with various diseases, particularly hepatobiliary diseases and bone diseases. Herein, we constructed a ratiometric sensor based on Förster resonance energy transfer (FRET) using strongly photoluminescent copper nanoclusters (Cu NCs) for the detection of ALP with high sensitivity and specificity. The cysteine-stabilized Cu NCs (Cys-Cu NCs) were synthesized through a ligand-exchange reaction and core-size etching focusing, which displayed bright photoluminescence (PL) with a quantum yield (QY) of 10.5 %. Multispectral characterization indicated that zwitterionic cysteine ligands without obvious steric hindrance could significantly enhance intra/inter-ligand-involved charge transfer, leading to a significant increase in fluorescence emission (∼14 folds) compared to precursor Cu NCs. A FRET-based ratiometric sensor for ALP detection was constructed by combining Cys-Cu NCs with a Cu2+-assisted oxidation reaction of o-phenylenediamine (OPD) to generate fluorescent 2,3-diaminophenazine (DAP). The strong coordination interaction between the ALP substrate and Cu2+ significantly affected the FRET process between Cys-Cu NCs and DAP, thereby altering the fluorescence ratio. Based on the specific response of ALP to its substrate, the ratiometric sensors showed good linear relationship within the range of 0.1-50 U/L, with a detection limit (LOD) of 0.075 U/L. Furthermore, the FRET-based ratiometric sensor was integrated with a polymer hydrogel to fabricate a portable hydrogel sensor for simple and visual detection of ALP.

Stacked long and short-term memory (SLSTM) - assisted terahertz spectroscopy combined with permutation importance for rapid red wine varietal identification

Mislabeling of low-value red wines as high-value ones is common, which seriously undermines consumer rights and interests. However, traditional sensory and chemical analysis methods have limitations, which highlights the need for novel detection techniques. To address above issues, terahertz time-domain spectroscopy (THz-TDS) combined with deep learning (DL) was employed to distinguish different red wine varieties quickly and non-destructively, contributing to correctly identifying red wine labels. Compared with the other models, the stacked long and short-term memory (SLSTM) model based on the first derivative (1-st der) spectra performed the best (Precision: 85.72 %, Recall: 85.61 %, F1-score: 85.59 %, Accuracy: 85.61 %). In addition, feature selection (FS) was used to explore the feasibility of improving model accuracy and reducing prediction time by eliminating redundant frequencies. Compared to full frequency, the 1-st der-SLSTM model based on permutation importance (PI) performed slightly lower (Precision: 84.42 %, Recall: 84.10 %, F1-score: 84.14 %, Accuracy: 84.18 %), but the prediction time was reduced by 2 s. Therefore, different models can be selected based on different detection needs by weighing accuracy and prediction time. In conclusion, the current research demonstrates that the SLSTM-assisted THz-TDS technology provides a novel approach for fast, accurate and non-destructive for fast, accurate and non-destructive discrimination of red wine labels, facilitating the maintenance of market discipline.

Quantitative native speciation of ppb-level metals in semiconductor-manufacturing-used strong acids and a base

The presence of metal species in solvents significantly impacts production yields in the semiconductor industry, particularly as the dimensions of integrated circuits continue to decrease. Therefore, it is imperative to control metal concentrations in solvents to levels as low as a few parts per billion (ppb) throughout fabrication processes. Effective purification methods are essential for removing various levels of contamination, and understanding the speciation of metals is crucial for achieving efficient purification. Conventional methods for the speciation of solution-phase metals include ion chromatography (IC) and ultraviolet-visible (UV-Vis) absorption spectroscopy. However, these techniques present limitations; for instance, IC can inadvertently alter species during the elution process, while the requirement for high-purity parts per million (ppm) concentrations of metals obscures the speciation of trace mixed samples using UV-Vis absorption spectroscopy. In this study, we present a quantitative speciation method for metals in their native states within strong acids and a base, utilizing the breakthrough curve (BTC) theory in conjunction with inductively coupled plasma-mass spectrometry (ICP-MS). Sodium, potassium, magnesium, calcium, iron, and copper serve as model systems for our investigations. The combination of BTC and ICP-MS provides insights into the species present and their respective abundances. Our findings indicate that breakthrough time (tBT) is predominantly influenced by the charge states and binding selectivity of the metal species and the concentrations of competing binding species. For scenarios where the product of the adsorption equilibrium constant (K) and the concentrations of a species at equilibrium (C) is significantly less than one (KC ≪ 1), tBT serves as a critical metric for assessing metal species at trace levels. Taking sodium (I) and potassium (I) at 10 ppb as representative examples, we discovered that tBT was accelerated by a factor of 5.7 when the concentration of the competing binding species ([H]+ in this study) was increased five-fold from 0.02 M to 0.1 M nitric acid (HNO3). Specifically, the tBT for sodium (I) decreased from 23 min to 4 min, while for potassium (I), it dropped from 114 min to 20 min. Furthermore, in the cases of magnesium (II) and copper (II) at 10 ppb, tBT was expedited by a factor of approximately 25; the tBT for magnesium (II) fell from 100 min to 4 min, and for copper (II), it decreased from 157 min to 6 min when the [H]+ concentration was increased five-fold from 0.1 M to 0.5 M HNO3. Additionally, we observed distinct species transformations for iron and copper, evidenced by markedly altered tBT in 0.1 M choline hydroxide solutions, which was observed to be less than 10 min. Anionic iron complexes and neutral copper particles were inferred, supported by ion exchange and UV-Vis absorption spectroscopic measurements. Furthermore, copper particles, potentially identified as copper (II) hydroxide or copper (II) oxide, exhibited a size distribution ranging from 200 to 400 nm with a peak at 300 nm, as characterized using particle analyzers. The advantages of the BTC theory-facilitated native quantitative speciation are anticipated to enhance informed decision-making for optimizing purification processes within the semiconductor industry.

Evaluation of structure-activity relationship for nitrogen-doped carbon-based metal-free electrocatalysts using electrochemiluminescence

Nitrogen doping enhances the catalytic performance of carbon-based metal-free electrocatalysts (C-MFECs) by modifying their chemical environment. Understanding the structure-catalytic activity relationship of nitrogen-doped (N-doped) C-MFECs is crucial for elucidating catalytic mechanisms and designing efficient electrocatalysts, but it remains challenging. Recently, reactive oxygen species (ROS)-triggered electrochemiluminescence (ECL) has shown great potential for uncovering these mechanisms due to its simple setup, low background signal, wide dynamic range, and high sensitivity. In this study, four types of N-doped C-MFECs with varying nitrogen dopant types (denoted as N-Cx, where x represents the annealing temperature) towards the electrochemical reduction of H2O2 are evaluated by monitoring the cathodic ECL of the luminol-H2O2 system in the low negative-potential region. Among these, N-C900, contains a higher content of graphitic nitrogen exhibits superior catalytic performance in activating H2O2 to generate significant amounts of ROS, as evidenced by its markedly enhanced ECL emission. The increased incorporation of graphitic nitrogen into the carbon plane likely improved H2O2 adsorption and its capacity to generate ROS. A sensitive antioxidant-mediated ECL platform was successfully developed for detecting antioxidant levels in orange juice, demonstrating potential for evaluating antioxidant capacity. This study not only provides insights into the catalytic mechanisms of N-doped C-MFECs but also highlights the potential of ECL as a versatile tool for studying and designing electrocatalysts.

A CRISPR/Cas13a system based on a dumbbell-shaped hairpin combined with DNA-PAINT to establish the DCP-platform for highly sensitive detection of Hantaan virus RNA

Rapid and sensitive detection of specific RNA sequences is crucial for clinical diagnosis, surveillance, and biotechnology applications. Currently, reverse transcription-quantitative polymerase chain reaction (RT-qPCR) is the gold standard for RNA detection; however, it is associated with long processing time, complex procedures, and a high false-positive rate. To address these challenges, we developed a novel sensing platform based on CRISPR/Cas13a that incorporates a dumbbell-shaped hairpin and DNA-PAINT for rapid, highly specific, and sensitive RNA analysis. By leveraging the CRISPR/Cas13a system, this platform enables the cleavage of dumbbell-shaped hairpins, which subsequently allows the cleaved primers to initiate cyclic amplification of fluorescent signals. These signals are further enhanced by the binding and dissociation phenomena inherent to DNA-PAINT technology, ultimately achieving remarkable triple signal amplification. Additionally, the system effectively discriminates Hantaan virus RNA from Seoul virus in real samples. Importantly, the platform can be easily adapted for the detection of other RNAs by simply reconfiguring the hybridization region of crRNA. In conclusion, this platform represents a "five-in-one" RNA detection approach that integrates reliability, versatility, robustness, high specificity, and superior quantitative capabilities. It provides novel insights for direct RNA detection based on CRISPR/Cas13a and demonstrates significant potential for advancement in viral diagnostics.

Human serum albumin-encapsulated near-infrared hemicyanine photosensitizers for viscosity imaging and enhanced photodynamic therapy

The research successfully developed a novel dual-function near-infrared photosensitizer, CyI, which is encapsulated with human serum albumin (HSA) to form CyI-HSA nanocomplex that can simultaneously monitor the viscosity of cancer cell and enhance the efficacy of photodynamic therapy (PDT). In vitro experiments demonstrated that compared with CyI alone, CyI-HSA has superior water solubility and high photostability, and can effectively prevent aggregation-caused quenching (ACQ) caused by π-π stacking. Additionally, singlet oxygen quantum yield of CyI-HSA as high as 27.4 % under 658 nm laser irradiation, indicating significant PDT potential. Cellular experiments further revealed that CyI-HSA can monitor intracellular viscosity with high sensitivity, while generating a substantial amount of singlet oxygen, promoting PDT and cell apoptosis. Treatment of HepG-2 cells with 1 µmol/L CyI-HSA reduced cell viability by only 13 % (Laser = 100 mW cm-2). Therefore, as a kind of nano-photosensitizer integrating diagnostic and therapeutic functions, CyI-HSA has a broad prospect in the application of near-infrared hemicyanine photosensitizers in photodynamic therapy.