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.

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.

Copper-catalyzed C-C bond cleavage coupling with CN bond formation toward mild synthesis of lignin-based benzonitriles

N-participated lignin depolymerization is of great importance for the transformation of waste lignin into value-added chemicals. The vast majority of developed strategies employ organic amines as nitrogen source, and considerable methods rely on excessive use of strong base, which suffers severe environmental issues. Herein, benzonitrile derivatives are synthesized from oxidized lignin β-O-4 model compounds in the presence of solid nitrogen source (NH4)2CO3 under mild, base-free conditions over commercially available copper catalyst. Mechanism studies suggest the transformation undergoes a one-pot, highly coupled cascade reaction path involving oxidative C-C bond cleavage and in-situ formation of CN bond. Of which, Cu(OAc)2 catalyzes the transfer of hydrogen from Cβ (Cβ-H) to Cα, leading to the cleavage of Cα-Cβ bonds to offer benzaldehyde derivative, this intermediate then reacts in-situ with (NH4)2CO3 to afford the targeted aromatic nitrile product. Tetrabutylammonium iodide (TBAI), acting as a promoter, plays a key role in breaking the Cα-Cβ bonds to form the intermediate benzaldehyde derivative. With this protocol, the feasibility of the production of value-added syringonitrile from birchwood lignin has been demonstrated. This transformation provides a sustainable approach to benzonitrile chemicals from renewable source of lignin.

Quantitative analysis of influencing factors to aerosol pH and its responses to PM2.5 and O3 pollution in a coastal city

Aerosol acidity (pH) plays an important role in the multiphase chemical processes of atmospheric particles. In this study, we demonstrated the seasonal trends of aerosol pH calculated with the ISORROPIA-II model in a coastal city of southeast China. We performed quantitative analysis on the various influencing factors on aerosol pH, and explored the responses of aerosol pH to different PM2.5 and O3 pollution levels. The results showed that the average aerosol pH was 2.92 ± 0.61, following the order of winter > spring > summer > autumn. Sensitivity tests revealed that SO42-, NHx, T and RH triggered the variations of aerosol pH. Quantitative analysis results showed that T (37.9%-51.2%) was the main factors affecting pH variations in four seasons, followed by SO42- (6.1%-23.7%), NHx (7.2%-22.2%) and RH (0-14.2%). Totally, annual mean meteorological factors (52.9%) and chemical compositions (41.3%) commonly contributed the aerosol ΔpH in the coastal city. The concentrations of PM2.5 was positively correlated with aerosol liquid water content (R2 = 0.53) and aerosol pH (R2 = 0.26), indicating that the increase in pH was related with the elevated NH4NO3 and decreased SO42-, and also the changes of T and RH. The Ox (O3 + NO2) was moderately correlated with aerosol pH (R2 = -0.48), attributable to the fact that the proportion of SO42- increased under high T and low RH conditions. The study strengthened our understanding of the contributions of influencing factors to aerosol pH, and also provided scientific evidences for chemical processes of atmospheric particles in coastal areas.

Bioactive mesoporous silica materials-assisted cancer immunotherapy

Immunotherapy is initially envisioned as a powerful approach to train immune cells within the tumor microenvironment (TME) and lymphoid tissues to elicit strong anti-tumor responses. However, clinical cancer immunotherapy still faces challenges, such as limited immunogenicity and insufficient immune response. Leveraging the advantages of mesoporous silica (MS) materials in controllable drug and immunomodulator release, recent efforts have focused on engineering MS with intrinsic immunoregulatory functions to promote robust, systemic, and safe anti-tumor responses. This review discusses advances in bioactive MS materials that address the challenges of immunotherapy. Beyond their role in on-demand delivery and drug release in response to the TME, we highlight the intrinsic functions of bioactive MS in orchestrating localized immune responses by inducing immunogenic cell death in tumor cells, modulating immune cell activity, and facilitating tumor-immune cell interactions. Additionally, we emphasize the advantages of bioactive MS in recruiting and activating immune cells within lymphoid tissues to initiate anti-tumor vaccination. The review also covers the challenges of MS-assisted immunotherapy, potential solutions, and future outlooks. With a deeper understanding of material-bio interactions, the rational design of MS with sophisticated bioactivities and controllable responsiveness holds great promise for enhancing the outcomes of personalized immunotherapy.

Pathogenesis, diagnosis, and treatment of epilepsy: electromagnetic stimulation-mediated neuromodulation therapy and new technologies

Epilepsy is a severe, relapsing, and multifactorial neurological disorder. Studies regarding the accurate diagnosis, prognosis, and in-depth pathogenesis are crucial for the precise and effective treatment of epilepsy. The pathogenesis of epilepsy is complex and involves alterations in variables such as gene expression, protein expression, ion channel activity, energy metabolites, and gut microbiota composition. Satisfactory results are lacking for conventional treatments for epilepsy. Surgical resection of lesions, drug therapy, and non-drug interventions are mainly used in clinical practice to treat pain associated with epilepsy. Non-pharmacological treatments, such as a ketogenic diet, gene therapy for nerve regeneration, and neural regulation, are currently areas of research focus. This review provides a comprehensive overview of the pathogenesis, diagnostic methods, and treatments of epilepsy. It also elaborates on the theoretical basis, treatment modes, and effects of invasive nerve stimulation in neurotherapy, including percutaneous vagus nerve stimulation, deep brain electrical stimulation, repetitive nerve electrical stimulation, in addition to non-invasive transcranial magnetic stimulation and transcranial direct current stimulation. Numerous studies have shown that electromagnetic stimulation-mediated neuromodulation therapy can markedly improve neurological function and reduce the frequency of epileptic seizures. Additionally, many new technologies for the diagnosis and treatment of epilepsy are being explored. However, current research is mainly focused on analyzing patients' clinical manifestations and exploring relevant diagnostic and treatment methods to study the pathogenesis at a molecular level, which has led to a lack of consensus regarding the mechanisms related to the disease.

Engineering M2 macrophage-derived exosomes modulate activated T cell cuproptosis to promote immune tolerance in rheumatoid arthritis

Nanomedicines for immune modulation have made advancements in the treatment of rheumatoid arthritis (RA). However, due to aberrations in patients' immune systems, inducing antigen-specific immune tolerance while halting disease progression remains a significant challenge. Here, we develop a highly targeted multifunctional nanocomplex, termed M2Exo@CuS-CitP-Rapa (M2CPR), with the aim of selectively inhibiting inflammatory immune reactions while promoting immune tolerance towards specific antigens. M2CPR specifically targets inflammatory tissues in RA, delivering CuS NPs, CitP, Rapa, and endogenous anti-inflammatory factors, thereby ameliorating the inflammatory joint microenvironment. CuS NPs induce Cuproptosis of activated T cells, whose fragments are engulfed by resident or recruited macrophages, resulting in abundant production of TGF-β. TGF-β acts synergistically with Rapa to induce the iDCs into tDCs. tDCs present CitP to Naive T cells, promoting Tregs differentiation. Tregs, in turn, produce more TGF-β, inducing tDCs differentiation, thereby establishing a cycle of immune tolerance. Through in vitro and in vivo experiments, we validate that M2CPR can induce robust and durable antigen-specific immune tolerance, offering a new paradigm for RA therapy.

On-demand reprogramming of immunosuppressive microenvironment in tumor tissue via multi-regulation of carcinogenic microRNAs and RNAs dependent photothermal-immunotherapy using engineered gold nanoparticles for malignant tumor treatment

The frequent immune escape of tumor cells and fluctuating therapeutic efficiency vary with each individual are two critical issues for immunotherapy against malignant tumor. Herein, we fabricated an intelligent core-shell nanoparticle (SNAs@CCMR) to significantly inhibit the PD-1/PD-L1 mediated immune escape by on-demand regulation of various oncogenic microRNAs and perform RNAs dependent photothermal-immunotherapy to achieve precise and efficient treatment meeting the individual requirements of specific patients by in situ generation of customized tumor-associated antigens. The SNAs@CCMR consisted of antisense oligonucleotides grafted gold nanoparticles (SNAs) as core and TLR7 agonist imiquimod (R837) functionalized cancer cell membrane (CCM) as shell, in which the acid-labile Schiff base bond was used to connect the R837 and CCM. During therapy, the acid environment of tumor tissue cleaved the Schiff base to generate free R837 and SNAs@CCM. The SNAs@CCM further entered tumor cells via CCM mediated internalization, and then specifically hybridized with over-expressed miR-130a and miR-21, resulting in effective inhibition of the migration and PD-L1 expression of tumor cells to avoid their immune escape. Meanwhile, the RNAs capture also caused significant aggregation of SNAs, which immediately generated photothermal agents within tumor cells to perform highly selective photothermal therapy under NIR irradiation. These chain processes not only damaged the primary tumor, but also produced plenty of tumor-associated antigens, which matured the surrounding dendritic cells (DCs) and activated anti-tumor T cells along with the released R837, resulting in the enhanced immunotherapy with suppressive immune escape. Both in vivo and in vitro experiments demonstrated that our nanoparticles were able to inhibit primary tumor and its metastasis via multi-regulation of carcinogenic microRNAs and RNAs dependent photothermal-immune activations, which provided a promising strategy to reprogram the immunosuppressive microenvironment in tumor tissue for better malignant tumor therapy.

Self-propelling intelligent nanomotor: A dual-action photothermal and starvation strategy for targeted deep tumor destruction

Delivering nanoparticles to deep tumor tissues while maintaining high therapeutic efficacy and minimizing damage to surrounding tissues has long posed a significant challenge. To address this, we have developed innovative self-propelling bowl-shaped nanomotors MSLA@GOx-PDA composed of mesoporous silica loaded with l-arginine and polydopamine, along with glucose oxidase (GOx). These nanomotors facilitate the generation of hydrogen peroxide through GOx-catalyzed glucose oxidation, thereby initiating nitric oxide production from l-arginine. This dual mechanism equips MSLA@GOx-PDA with the robust motility required for deep tumor tissue penetration while depleting essential nutrients necessary for tumor growth, consequently impeding tumor progression. In addition, near-infrared lasers have the significant advantage of being depth-penetrating and non-invasive, allowing real-time fluorescence imaging and guiding dopamine-mediated mild photothermal therapy. Notably, starvation therapy depletes intracellular adenosine triphosphate and inhibits the synthesis of heat shock proteins, thus overcoming the Achilles' heel of mild photothermal therapy and significantly enhancing the efficacy of this therapy with encouraging synergistic anti-tumour effects. Overall, the integration of biochemical and optics strategies in this nanomotor platform represents a significant advancement in deep-tissue tumor therapy. It has substantial clinical translational value and is expected to have a transformative impact on future cancer treatments.

Computational detangling chalcogen elements substitutions associated ESDPT mechanism for oxazolinyl-substituted hydroxyfluorene derivatives

In view of the distinguished photochemical and photobiological characteristics of oxazolinyl-substituted hydroxyfluorene and its derivatives, herein, we mainly focus on probing into excited state behaviors of the novel 9,9-dimethyl-3,6-dihydroxy-2,7-bis(4,5-dihydro-4,4-dimethyl-2-oxazolyl) fluorene (Oxa-OH) derivatives. In light of the significant effects resulting from substituting oxygen elements, three Oxa-OH derivatives (i.e., Oxa-OO, Oxa-SS and Oxa-SeSe fluorophores) are considered in this work. For these three different fluorophores, we detangle the effects of atomic electronegativity and charge recombination related to oxygen elements in excited state double proton transfer (ESDPT) processes. Because of the low potential energy barriers, we confirm the ESDPT happens by the sequential type. Based on heterosubstituted Oxa-OS and Oxa-OSe compounds, we further verify the chalcogen atomic-electronegativity-regulated stepwise ESDPT mechanism. We sincerely wish our work could provide a theoretical reference for proving this novel mechanism of ESDPT experimentally.

Blue-/near-infrared light-triggered photochromism in a reinforced acceptor-acceptor type dithienylethene with aggregation-induced emission

The development of photochromic dithienylethene (DTE) derivatives activated by visible light, particularly those exhibiting aggregation-induced emission (AIE) properties, is highly sought after for applications in photoelectric functional materials and biological systems. In this study, we rationally designed and successfully synthesized a novel cyanostilbene- and nitro-functionalized DTE derivative (6) featuring a reinforced acceptor (A)-DTE-acceptor (A) structural motif. Each of the two cyanostilbene fragments bearing nitrobenzene groups imparts both electron-withdrawing effects and AIE characteristics, thereby ensuring efficient visible light-driven photochromic performance. The chemical structure of compound 6 was characterized using standard techniques, including 1H NMR, 13C NMR, and HRMS. As anticipated, the resulting DTE (6) demonstrates efficient photochromism in various solvents when alternately irradiated with blue light (λ = 460-470 nm) and near-infrared (NIR) light (λ = 730-740 nm). Prior to blue light irradiation, the AIE performance and solid-state luminescence behavior were assessed. Furthermore, DTE (6) exhibits enhanced photoswitching behavior within a poly(methyl methacrylate) (PMMA) film. The experimental findings are corroborated by density functional theory (DFT) calculations. Ultimately, this derivative has been successfully employed for information recording and erasing, thereby demonstrating its potential for information storage and encryption.

Novel NIR fluorescent probe based on BODIPY for diagnosis and treatment evaluation of alcoholic liver disease via visualizing HClO fluctuation

Alcoholic liver disease (ALD) is gradually becoming common due to the increasing number of drinkers worldwide, which is a serious threat to human physical and mental health. In the process of ALD, it is often accompanied by the occurrence of inflammation, which induce high expression of reactive oxygen species including HClO. In this work, we successfully fabricated a NIR fluorescent probe BDP-ENE-Fur-HClO for real-time imaging alcoholic liver disease via tracing HClO. The probe displayed good sensitivity and specificity, rapid recognition speed and NIR emitting (700 nm) for detection of HClO in vitro. Based on the remarkable performances, probe was capable of tracing endogenous/exogenous HClO in living cells without interference from other ROS as well as in ALD cell model. Additionally, probe could monitor the exogenous HClO in normal mice and high expression of HClO in the peritonitis mice, that accomplishing the diagnosis of inflammation. What's more, one simulated hazardous drinking ALD mice model and simulated excessive drinking (a type of alcohol use disorder) ALD mice model were developed, probe could image the alcoholic liver injury of mice by monitoring the HClO fluctuation in ALD mice, which affording a valid instrument for the diagnosis of ALD. Ultimately, after hepatoprotective drug administrating to the models, probe could triumphantly evaluate the treatment effect of drug on ALD.

Fabrication of the multifunctional Pd modified NiCuFe Prussian blue analogue nanoplatform and its sensitive colorimetric detection of L-cysteine

It is essential to establish a simple, effective and sensitive platform for L-Cysteine (L-Cys) detection because the level of L-Cys is related to many diseases in the human body. Herein, we successfully fabricated polyaniline bridging NiCuFe Prussian blue analogue@palladium (NiCuFe@Pd) nanocomposite with integration of photothermal conversion performance and catalytic performance. And, various spectroscopic and microscopic techniques were adopted to prove the formation of the nanocomposite. 4-nitrothiophenol and 3,3',5,5'-tetramethylbenzidine (TMB) were employed to prove the catalytic activity of the nanocomposite. Due to the catalytic activity, the nanocomposite was used as a nanoplatform for colorimetric detection of L-Cys, which showed high sensitivity with a detection limit as low as 0.027 μM. In addition, the excellent photothermal conversion performance makes it a potential candidate for photothermal therapy for various diseases. This study may be beneficial to promote the construction of novel nanostructures and their medical application.

Modulating the D-band center of mn and mitigating O vacancies with amino groups for enhanced long-cycle alkaline-manganese batteries

Manganese oxide is a promising cathode material for rechargeable batteries due to its high theoretical specific capacity. However, its practical application is hindered by its poor conductivity and rapid capacity decay caused by Jahn-Teller distortion during charging and discharging. This work introduces Na2EDTA during the synthesis of MnO2, and the amino group is introduced by adsorption to deposit to form N-doped MnO2. Alkaline N-doped MnO2 battery upshifts the d-band center of Mn, improves the conductivity of MnO2 and the formation energy of O vacancies during the charge-discharge process, and suppresses Jahn Teller distortion. As a result, N-doped MnO2 achieves a high capacity of up to 197mAh g-1 and excellent capacity retention of 94.2% over 250 cycles with slower voltage decay. This strategy enables the material with high cycling performance for single-electron discharge secondary alkaline manganese batteries.

A brief review of preparation and applications of monolithic aerogels in atmospheric environmental purification

Monolithic aerogels are promising candidates for use in atmospheric environmental purification due to their structural advantages, such as fine building block size together with high specific surface area, abundant pore structure, etc. Additionally, monolithic aerogels possess a unique monolithic macrostructure that sets them apart from aerogel powders and nanoparticles in practical environmental clean-up applications. This review delves into the available synthesis strategies and atmospheric environmental applications of monolithic aerogels, covering types of monolithic aerogels including SiO2, graphene, metal oxides and their combinations, along with their preparation methods. In particular, recent developments for VOC adsorption, CO2 capture, catalytic oxidation of VOCs and catalytic reduction of CO2 are highlighted. Finally, challenges and future opportunities for monolithic aerogels in the atmospheric environmental purification field are proposed. This review provides valuable insights for designing and utilizing monolithic aerogel-based functional materials.

siRNA-based nanotherapeutic approaches for targeted delivery in rheumatoid arthritis

Rheumatoid arthritis (RA), characterized as a systemic autoimmune ailment, predominantly results in substantial joint and tissue damage, affecting millions of individuals globally. Modern treatment modalities are being explored as the traditional RA therapy with non-specific immunosuppressive drugs showcased potential side effects and variable responses. Research potential with small interfering RNA (siRNA) depicted potential in the treatment of RA. These siRNA-based therapies could include genes encoding pro-inflammatory cytokines like TNF-α, IL-1, and IL-6, as well as other molecular targets such as RANK, p38 MAPK, TGF-β, Wnt/Fz complex, and HIF. By downregulating the expression of these genes, siRNA-based nanoformulations can attenuate inflammation, inhibit immune system dysregulation, and prevent tissue damage associated with RA. Strategies of delivering siRNA molecules through nanocarriers could be targeted to treat RA effectively, where specific genes associated with this autoimmune disease pathology can be selectively silenced. Additionally, simultaneous targeting of multiple molecular pathways may offer synergistic therapeutic benefits, potentially leading to more effective and safer therapeutic strategies for RA patients. This review critically highlights the in-depth pathology of RA, RNA interference-mediated molecular targets, and nanocarrier-based siRNA delivery strategies, along with the challenges and opportunities to harbor future solutions.

A nanoporous electrochemical aptamer-based sensors for rapid detection of cardiac troponin I in blood

Acute myocardial infarction (AMI) is one of the top contributors to global disease mortality. AMI biomarkers, such as cardiac troponin I (cTnI), are often detected with enzyme-linked immunosorbent assay (ELISA) that suffers from several well-known drawbacks such as poor stability and slow and cumbersome operation. Therefore, it is necessary to develop a new analytical technique that can rapidly analyse and detect cTnI for early screening of AMI. In this work, a nanoporous electrochemical aptamer-based (E-AB) sensor for rapid and sensitivite detect of cTnI was designed. Firstly, the aptamer was truncated, and then molecular docking simulation and circular dichroism (CD) were used to screen for aptamers with significant conformational changes when binding to the target, in order to enhance the sensitivity of E-AB sensors. Subsequently, nanoporous electrodes with active area 20 times higher than that of smooth electrodes were fabricated by electrochemical alloying/dealloying, which enabled E-AB sensors to obtain higher signal-to-noise ratios, providing favorable assurance for the detection results. Under optimal conditions, E-AB sensors could specifically detect cTnI in serum and blood with a detection limit of 1 pg/mL. At the same time, the sensor and enzyme-linked immunoassay (ELISA) had identical detection results when measuring target levels from real clinical samples. Furthermore, the sensor exhibited good reproducibility, stability, providing a simple and low-cost method for detecting cTnI, which is expected to help early AMI patients obtain accurate diagnosis.

Discovery and Characterization of Unusual O-Linked Glycosylation of IgG4 Antibody Using LC-MS

BACKGROUND

Consensus is that immunoglobulin IgG4 contains only N-linked glycosylation. The analysis of several batches of commercial biopharmaceutical product Dupixent using top-down intact mass spectrometry revealed that this IgG4 features a small amount of O-linked glycosylation in the Fab region. This is the first report of an O-linked glycosylation in an IgG4 antibody.

METHODS

Monoclonal antibody solutions were subjected to cation exchange (CEX) and reverse phase (RP) chromatography and/or additional preconcentration/fractionation methods to prepare samples for subsequent analysis. Advanced MS analysis and fragmentation techniques (HCD, ETD, and EThcD) were employed to localize the O-linked glycosylation as well as elucidate the structure of the glycan(s).

RESULTS

O-linked glycosylation in the IgG4 dupilumab was discovered by intact-MS. The probable location was narrowed down to four sites in the CH1 domain, and the structure of the O-linked glycan was determined to be of Core 1 type. The relative quantities of the modifications were low, but the glycosylation was consistently detected in several batches of Dupixent.

CONCLUSIONS

We discovered a rare glycosylation modification on dupilumab, an IgG4 antibody. The O-linked glycosylation was characterized and localized in the Fab region.

Pharmaceutical strategies for optimized mRNA expression

Messenger RNA (mRNA)-based immunotherapies and protein in situ production therapies hold great promise for addressing theoretically all the diseases characterized by aberrant protein levels. The safe, stable, and precise delivery of mRNA to target cells via appropriate pharmaceutical strategies is a prerequisite for its optimal efficacy. In this review, we summarize the structural characteristics, mode of action, development prospects, and limitations of existing mRNA delivery systems from a pharmaceutical perspective, with an emphasis on the impacts from formulation adjustments and preparation techniques of non-viral vectors on mRNA stability, target site accumulation and transfection efficiency. In addition, we introduce strategies for synergistical combination of mRNA and small molecules to augment the potency or mitigate the adverse effects of mRNA therapeutics. Lastly, we delve into the challenges impeding the development of mRNA drugs while exploring promising avenues for future advancements.

Photoclick surface modification of MOF-808 for galactose-mediated targeted chemotherapy

Controllable surface modification of nanoparticulate drug delivery vectors is key to enhancing specific desirable properties such as colloidal stability, targeting, and stimuli-responsive cargo release. Metal-organic frameworks (MOFs) have been proposed as potential delivery devices, with surface modification achieved by various bioconjugate "click" reactions, including copper-catalysed and strain-promoted azide-alkyne cycloaddition. Herein, we show that photo-induced nitrile imine-mediated tetrazole-ene cycloaddition (NITEC) can be used to surface-modify tetrazole-appended Zr MOFs with maleimides, and vice versa, with the extent of this traceless surface functionalisation controlled by the length of photoirradiation. This "photoclick" surface modification protocol is exemplified by the decorating of carboplatin-loaded MOF-808 with galactose units to target asialoglycoprotein receptors of specific cancer cell types. Targeting towards HepG2 cells, which overexpress these receptors, is indicated by enhanced endocytosis and cytotoxicity in both two- and three-dimensional cell cultures compared to other cell lines. The study shows both the power of the NITEC protocol for functionalisation of MOFs, and also the benefits of carbohydrate targeting in drug delivery vectors, with scope for significant additional work diversifying the surface targeting units available for nanoparticle functionalisation under these mild, biocompatible "photoclick" conditions.

Ultra-pH-sensitive nanoplatform for precise tumor therapy

The emergence of precision cancer treatment has triggered a paradigm shift in the field of oncology, facilitating the implementation of more effective and personalized therapeutic approaches that enhance patient outcomes. The pH of the tumor microenvironment (TME) plays a pivotal role in both the initiation and progression of cancer, thus emerging as a promising focal point for precision cancer treatment. By specifically targeting the acidic conditions inherent to the tumor microenvironment, innovative therapeutic interventions have been proposed, exhibiting significant potential in augmenting treatment efficacy and ameliorating patient prognosis. The concept of ultra-pH-sensitive (UPS) nanoplatform was proposed several years ago, demonstrating exceptional pH sensitivity and an adjustable pH transition point. Subsequently, diverse UPS nanoplatforms have been actively explored for biomedical applications, enabling the loading of fluorophores, therapeutic drugs, and photosensitizers. This review aims to elucidate the design strategy and response mechanism of the UPS nanoplatform, with a specific emphasis on its applications in surgical therapy, immunotherapy, drug delivery, photodynamic therapy, and photothermal therapy. The potential and challenges of translating in the clinic on UPS nanoplatforms are finally explored. Thanks to its responsive and easily modifiable nature, the integration of multiple functional units within a UPS nanoplatform holds great promise for future advancements in tumor precision theranositcs.

Harnessing Nature's ingenuity to engineer butterfly-wing-inspired photoactive nanofiber patches for advanced postoperative tumor treatment

Postoperative tumor treatment necessitates a delicate balance between eliminating residual tumor cells and promoting surgical wound healing. Addressing this challenge, we harness the innovation and elegance of nature's ingenuity to develop a butterfly-wing-inspired photoactive nanofiber patch (WingPatch), aimed at advancing postoperative care. WingPatch is fabricated using a sophisticated combination of electrostatic spinning and spraying techniques, incorporating black rice powder (BRP) and konjac glucomannan (KGM) into a corn-derived polylactic acid (PLA) nanofiber matrix. This fabrication process yields a paclitaxel-infused porous nanofiber architecture that mirrors the delicate patterns of butterfly wings. Meanwhile, all-natural composites have been selected for their strategic roles in postoperative recovery. BRP offers the dual benefits of photothermal therapy and antibacterial properties, while KGM enhances both antibacterial effectiveness and tissue regeneration. Responsive to near-infrared light, WingPatch ensures robust tissue adhesion and initiates combined photothermal and chemotherapeutic actions to effectively destroy residual tumor cells. Crucially, it simultaneously prevents infections and promotes wound healing throughout the treatment process. Its effectiveness has been confirmed by animal studies, and WingPatch significantly improves treatment outcomes in both breast and liver tumor models. Thus, WingPatch exemplifies our dedication to leveraging natural world's intricate patterns and inventiveness to propel postoperative care forward.

Engineering cell membrane-camouflaged COF-based nanosatellite for enhanced tumor-targeted photothermal chemoimmunotherapy

Dendritic cells (DCs) activation is crucial for regulating the antitumor immune response. However, the tumor's immunosuppressive environment significantly impedes antigen presentation and DCs maturation, thereby limiting the effectiveness of cancer immunotherapy. To address this challenge, we developed tumor cell membrane-coated covalent organic framework (COF) nanoparticles, loaded with mannose-modified gold nanoparticles and doxorubicin (Dox). This created a cell membrane-camouflaged COF-based nanosatellite designed to enhance tumor-targeted chemoimmunotherapy. The nanosatellite exhibits distinct photothermal properties and releases Dox in a pH-sensitive manner, targeting tumor cells to induce immunogenic cell death (ICD) and expose a wealth of antigens. Crucially, the COF structure is selectively degraded to release mannose-modified gold nanoparticles in the acidic environment. These nanoparticles capture antigens from the ICD and efficiently transport them to lymph nodes rich in DCs, facilitated by mannose receptor mediation. As a result, antigens are effectively presented to DCs, activating the immune response, significantly hindering tumor growth and lung metastasis in mice, and extending survival. This study pioneered innovative nano-preparations aimed at enhancing tumor immunotherapy.

A water probe for direct pH measurement of individual particles via micro-Raman spectroscopy

The acidity of atmospheric aerosols influences fundamental physicochemical processes that affect climate and human health. We recently developed a novel and facile water-probe-based method for directly measuring of the pH for micrometer-size droplets, providing a promising technique to better understand aerosol acidity in the atmosphere. The complex chemical composition of fine particles in the ambient air, however, poses certain challenges to using a water-probe for pH measurement, including interference from interactions between compositions and the influence of similar compositions on water structure. To explore the universality of our method, it was employed to measure the pH of ammonium, nitrate, carbonate, sulfate, and chloride particles. The pH of particles covering a broad range (0-14) were accurately determined, thereby demonstrating that our method can be generally applied, even to alkaline particles. Furthermore, a standard spectral library was developed by integrating the standard spectra of common hydrated ions extracted through the water-probe. The library can be employed to identify particle composition and overcome the spectral overlap problem resulting from similar effects. Using the spectral library, all ions were identified and their concentrations were determined, in turn allowing successful pH measurement of multicomponent (ammonium-sulfate-nitrate-chloride) particles. Insights into the synergistic effect of Cl-, NO3-, and NH4+ depletion obtained with our approach revealed the interplay between pH and volatile partitioning. Given the ubiquity of component partitioning and pH variation in particles, the water probe may provide a new perspective on the underlying mechanisms of aerosol aging and aerosol-cloud interaction.

A mixed-organic ligands Ru(bpy)32+@Zn mMOFs-NH2 nanoreactors integrated co-reaction accelerator and morphologic regulator for the electrochemiluminescence detection of ATP

The functionalized architecture within the nanoreactor could dramatically change the electron transport and reaction efficiency of ECL during electrochemical processes. Here, we've devised a novel mixed-ligand strategy that combines co-reaction accelerator and morphologic regulator onto the same metal node. This innovative approach effectively addressed the critical issue that some co-reactants cannot be covalently linked due to their special states, while enhancing the stability and electroactivity of MOFs nanoreactors. Ru(bpy)32+ was in-situ encapsulated within Zn mMOFs-NH2 nanocages in which the 2-aminoterephthalic acid (NH2-BDC) ligand functioned as an effective co-reaction accelerator. While S2O82- underwent electron exchange on the surface of GCE to form SO4•-, Zn mMOFs-NH2 was electrochemically oxidized to Zn mMOFs-NH•, which could significantly catalyze S2O82- to form SO4•-. This greatly increased the local concentration of SO4•- in the vicinity of Ru(bpy)32+, thus achieving self-enhancing ECL. At the same time, 1,4-benzenedicarboxylic acid (BDC) ligands were used as morphologic regulator, yielding ultra-thin MOFs nanosheets that significantly boosted the loading capacity for Ru(bpy)32+ and enhanced electrical conductivity. The luminous efficiency of Ru(bpy)32+ is further enhanced by this synergy. A highly sensitive ECL biosensor was crafted for the detection of ATP. Optimal conditions allowed a robust linear correlation between the ECL intensity and the logarithm of ATP concentration, enabling a sensitive detection limit down to 1.18 nM. Our findings underscore the exceptional self-enhanced ECL properties of the devised Ru(bpy)32+@Zn mMOFs-NH2 nanoreactors, presenting a novel and promising platform for biomolecular analysis.

Insight into the bimetallic structure sensibility of catalytic nitrate reduction over Pd-Cu nanocrystals

Catalytic reduction of nitrate over bimetallic catalysts has emerged as a technology for sustainable treatment of nitrate-containing groundwater. However, the structure of bimetallic has been much less investigated for catalyst optimization. Herein, two main types of Pd-Cu bimetallic nanocrystal structures, heterostructure and intermetallic, were prepared and characterized using high-resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The results show that two individual Pd and Cu nanocrystals with a mixed interface exist in the heterostructure nanocrystals, while Pd and Cu atoms are uniformly distributed across the intermetallic Pd-Cu nanocrystals. The catalytic nitrate reduction experiments were carried out in a semibatch reactor under constant hydrogen flow. The nitrate conversion rate of the heterostructure Pd-Cu nanocrystals supported on α-Al2O3, γ-Al2O3, SBA-15, and XC-72R exhibited 3.82-, 6.76-, 4.28-, 2.44-fold enhancements relative to the intermetallic nanocrystals, and the nitrogen and nitrite were the main products for the heterostructure and intermetallic Pd-Cu nanocrystals, respectively. This indicates that the catalytic nitrate reduction over Pd-Cu catalyst is sensitive to the bimetallic structures of the catalysts, and heterostructure bimetallic nanocrystals exhibit better catalytic performances on both the activity and selectivity, which may provide new insights into the design and optimization of catalysts to improve catalytic activity and selectivity for nitrate reduction in water.

High-performance plasmonics nanostructures in gas sensing: a comprehensive review

Plasmonic nanostructures have emerged as indispensable components in the construction of high-performance gas sensors, playing a pivotal role across diverse applications, including industrial safety, medical diagnostics, and environmental monitoring. This review paper critically examines seminal research that underscores the remarkable efficacy of plasmonic materials in achieving superior attributes such as heightened sensitivity, selectivity, and rapid response times in gas detection. Offering a synthesis of pivotal studies, this review aims to furnish a comprehensive discourse on the contemporary advancements within the burgeoning domain of plasmonic gas sensing. The featured investigations meticulously scrutinize various plasmonic structures and their applications in detecting gases like carbon monoxide, carbon dioxide, hydrogen and nitrogen dioxide. The discussed frameworks encompass cutting-edge approaches, spanning ideal absorbers, surface plasmon resonance sensors, and nanostructured materials, thereby elucidating the diverse strategies employed for advancing plasmonic gas sensing technologies.

Tumor microenvironment-activated polypeptide nanoparticles for oncolytic immunotherapy

Cationic oncolytic polypeptides have gained increasing attention owing to their ability to directly lyse cancer cells and activate potent antitumor immunity. However, the low tumor cell selectivity and inherent toxicity induced by positive charges of oncolytic polypeptides hinder their systemic application. Herein, a tumor microenvironment-responsive nanoparticle (DNP) is developed by the self-assembly of a cationic oncolytic polypeptide (PLP) with a pH-sensitive anionic polypeptide via electrostatic interactions. After the formation of DNP, the positive charges of PLP are shielded. DNPs can keep stable in physiological conditions (pH 7.4) but respond to acidic tumor microenvironment (pH 6.8) to release oncolytic PLP. As a result, DNPs evoke potent immunogenic cell death by disrupting cell membranes, damaging mitochondria and increasing intracellular levels of reactive oxygen species. In vivo results indicate that DNPs significantly improve the biocompatibility of PLP, and inhibit tumor growth, recurrence and metastasis by direct oncolysis and activation of antitumor immune responses. In summary, these results indicate that pH-sensitive DNPs represent a prospective strategy to improve the tumor selectivity and biosafety of cationic polymers for oncolytic immunotherapy.

Biomimetic polymeric nanoreactors with photooxidation-initiated therapies and reinvigoration of antigen-dependent and antigen-free immunity

Immune cell-mediated anticancer modalities usually suffer from immune cell exhaustion and limited efficacy in solid tumors. Herein, the oxygen-carrying biomimetic nanoreactors (BNR2(O2)) have been developed with photooxidation-driven therapies and antigen-dependent/antigen-free immune reinvigoration against xenograft tumors. The BNR2(O2) composes polymeric nanoreactors camouflaged with cancer cell membranes can efficiently target homotypic tumors. It continuously releases O2 to boost intracellular reactive oxygen species (ROS) to oxide diselenide bonds, which controllably releases seleninic acids and anti-folate Pemetrexed compared to hydrogen peroxide and glutathione incubation. The O2-rich microenvironment sensitizes Pemetrexed and blocks programmed cell-death ligand 1 (PD-L1) to reverse T cell immunosuppression. The ROS and Pemetrexed upregulate pro-apoptosis proteins and inhibit folate-related enzymes, which cause significant apoptosis and immunogenic cell death to stimulate dendritic cell maturation for improved secretion of cytokines, expanding antigen-dependent T cell immunity. Furthermore, by regulating the release of seleninic acids, the checkpoint receptor human leukocyte antigen E of tumor cells can be blocked to reinvigorate antigen-free natural killer cell immunity. This work offers an advanced antitumor strategy by bridging biomimetic nanoreactors and modulation of multiple immune cells.

Barrierless reactions of C2 Criegee intermediates with H2SO4 and their implication to oligomers and new particle formation

The formation of oligomeric hydrogen peroxide triggered by Criegee intermediate maybe contributes significantly to the formation and growth of secondary organic aerosol (SOA). However, to date, the reactivity of C2 Criegee intermediates (CH3CHOO) in areas contaminated with acidic gas remains poorly understood. Herein, high-level quantum chemical calculations and Born-Oppenheimer molecular dynamics (BOMD) simulations are used to explore the reaction of CH3CHOO and H2SO4 both in the gas phase and at the air-water interface. In the gas phase, the addition reaction of CH3CHOO with H2SO4 to generate CH3HC(OOH)OSO3H (HPES) is near-barrierless, regardless of the presence of water molecules. BOMD simulations show that the reaction at the air-water interface is even faster than that in the gas phase. Further calculations reveal that the HPES has a tendency to aggregate with sulfuric acids, ammonias, and water molecules to form stable clusters, meanwhile the oligomerization reaction of CH3CHOO with HPES in the gas phase is both thermochemically and kinetically favored. Also, it is noted that the interfacial HPES- ion can attract H2SO4, NH3, (COOH)2 and HNO3 for particle formation from the gas phase to the water surface. Thus, the results of this work not only elucidate the high atmospheric reactivity of C2 Criegee intermediates in polluted regions, but also deepen our understanding of the formation process of atmospheric SOA induced by Criegee intermediates.

Probing antimicrobial synergy by novel lipopeptides paired with antibiotics

Antimicrobial resistance (AMR) is fast becoming a major global challenge in both hospital and community settings as many current antibiotics and treatment processes are under the threat of being rendered less effective or ineffective. Synergistic combination of an antibiotic and an aiding agent with a different set of properties provides an important but largely unexploited option to 'repurpose' existing biomaterial's space while addressing issues of potency, spectrum, toxicity and resistance in early stages of antimicrobial drug discovery. This work explores how to combine tetracycline/minocycline (TC/MC) with a broad-spectrum antimicrobial lipopeptide that has been designed to improve the efficiency of membrane targeting and intramembrane accumulation, thereby enhancing antimicrobial efficacy. Experimental measurements of fractional inhibition concentration index (FICI) were undertaken from binary antibiotic-lipopeptide combinations. Most FICI values were found to be lower than 0.5 against both Gram-positive and Gram-negative bacterial strains studied including 3 AMR strains, revealing strong synergetic effects via favorable membrane-lytic interactions. The antimicrobial actions of this type of binary combinations are featured by the fast time-killing and high TC/MC uptake, benefited from effective membrane-lytic disruptions by the lipopeptide. This study thus provides an important mechanistic understanding of the combined antibiotic-lipopeptide approach to improve the therapeutic potential of conventional antibiotics by illustrating how amphiphilic lipopeptide-antibiotic combinations interact with biological membranes, providing a promising alternative to combat AMR through rational design of lipopeptide as an aiding agent.

The application and prospects of drug delivery systems in idiopathic pulmonary fibrosis

Idiopathic pulmonary fibrosis (IPF) is an interstitial lung disease primarily affecting elderly individuals aged >65 years and has a poor prognosis. No effective treatment is currently available for IPF. The two antipulmonary fibrosis drugs nintedanib and pirfenidone approved by the FDA in the United States have somewhat decelerated IPF progression. However, the side effects of these drugs can lead to poor patient tolerance and compliance with the medications. Researchers have recently developed various methods for IPF treatment, such as gene silencing and pathway inhibitors, which hold great promise in IPF treatment. Nevertheless, the nonselectivity and nonspecificity of drugs often affect their efficacies. Drug delivery systems (DDS) are crucial for delivering drugs to specific target tissues or cells, thereby minimizing potential side effects, enhancing drug bioavailability, and reducing lung deposition. This review comprehensively summarizes the current state of DDS and various delivery strategies for IPF treatment (e.g., nano-delivery, hydrogel delivery, and biological carrier delivery) to completely expound the delivery mechanisms of different drug delivery carriers. Subsequently, the advantages and disadvantages of different DDS are fully discussed. Finally, the challenges and difficulties associated with the use of different DDS are addressed so as to accelerate their rapid clinical translation.

Determination of polystyrene nanospheres and other nanoplastics in water via binding with organic dyes by capillary electrophoresis with laser-induced fluorescence detection

The purpose of this research work was to develop a new method for the quantitative analysis of water samples containing nanoplastics in the presence of microplastics and other colloidal particles. Our approach involved a mixture of fluorescent organic dyes that was added to each water sample for binding with the target nanoplastics. Binding was proven by zeta potential measurements that revealed the point of zero charge shifting from pH 4 for polystyrene nanoparticles, to pH 6.13 after binding with the dye mixture. Centrifugation effectively separated the free dyes from all dye-bound particles in the heterogeneous mixture, thus eliminating any potential interference. Electrokinetic injection of the free dyes in the supernatant allowed efficient separation by capillary electrophoresis (CE), for accurate quantitation individually with laser-induced fluorescence detection. A diode laser was operated at λex of 450 nm to induce fluorescence from the dyes, and an optical interference filter to collect only emission photons with λem of 520 nm. The fluorescence peak intensity decreased for each dye, thereby determining the total binding activity of all plastics and other particles. This new method enables high-throughput screening of water samples for nanoplastics, based on their fast binding with organic dyes in 5 min, rapid analytical separation of dyes by capillary electrophoresis within 10 min, and instantaneous fluorescence intensity measurement of individual dye peaks. Binding percentages as high as 149(±2) %/μg of 9.5-nm polystyrene nanoparticles were attained when using a concentration of 125 μg/mL for each dye. The binding mechanism was mainly attributed to hydrophobic interaction and modified by electrostatic forces. Binding of the four dyes with polystyrene microparticles, casein micelles, and transition metal oxide nanoparticles was verified to demonstrate minimal interference. The method was successfully applied to rapid testing of water samples from various sources, ranging from drinking fountains and household faucets to flowing rivers. The method also applied to a decontamination study wherein a removal of 94 % polystyrene nanospheres (diameter = 80 nm) was achieved by adding only 20 mg of casein powder into 1.6 mL of water containing 36 mg of the nanoplastics initially.

Theoretical calculation on degradation mechanism of novel copolyesters under CALB enzyme

Poly(butylene succinate-co-furandicarboxylate) (PBSF) and poly(butylene adipate-co-furandicarboxylate) (PBAF) are novel furandicarboxylic acid-based biodegradable copolyesters with great potential to replace fossil-derived terephthalic acid-based copolyesters such as poly(butylene succinate-co-terephthalate) (PBST) and poly(butylene adipate-co-terephthalate) (PBAT). In this study, quantum chemistry techniques after molecular dynamics simulations are employed to investigate the degradation mechanism of PBSF and PBAF catalyzed by Candida antarctica lipase B (CALB). Computational analysis indicates that the catalytic reaction follows a four-step mechanism resembling the ping-pong bibi mechanism, with the initial two steps being acylation reactions and the subsequent two being hydrolysis reactions. Notably, the first step of the hydrolysis is identified as the rate-determining step. Moreover, by introducing single-point mutations to expand the substrate entrance tunnel, the catalytic distance of the first acylation step decreases. Additionally, energy barrier of the rate-determining step is decreased in the PBSF system by site-directed mutations on key residues increasing hydrophobicity of the enzyme's active site. This study unprecedently show the substrate binding pocket and hydrophobicity of the enzyme's active site have the potential to be engineered to enhance the degradation of copolyesters catalyzed by CALB.

Recent progress in cancer vaccines and nanovaccines

Vaccine science, nanotechnology, and immunotherapy are at the forefront of cancer treatment strategies, each offering significant potential for enhancing tumor-specific immunity and establishing long-lasting immune memory to prevent tumor recurrence. Despite the promise of these personalized and precision-based anti-cancer approaches, challenges such as immunosuppression, suboptimal immune activation, and T-cell exhaustion continue to hinder their effectiveness. The limited clinical success of cancer vaccines often stems from difficulties in identifying effective antigens, efficiently targeting immune cells, lymphoid organs, and the tumor microenvironment, overcoming immune evasion, enhancing immunogenicity, and avoiding lysosomal degradation. However, numerous studies have demonstrated that integrating nanotechnology with immunotherapeutic strategies in vaccine development can overcome these challenges, leading to potent antitumor immune responses and significant progress in the field. This review highlights the critical components of cancer vaccine and nanovaccine strategies for immunomodulatory antitumor therapy. It covers general vaccine strategies, types of vaccines, antigen forms, nanovaccine platforms, challenges faced, potential solutions, and key findings from preclinical and clinical studies, along with future perspectives. To fully unlock the potential of cancer vaccines and nanovaccines, precise immunological monitoring during early-phase trials is essential. This approach will help identify and address obstacles, ultimately expanding the available options for patients who are resistant to conventional cancer immunotherapies.

Tetrahedral DNA nanostructures, graphene and carbon nanodots-based electrochemiluminescent biosensor for BRCA1 gene mutation detection

In this study, we present a novel electrochemiluminescent DNA biosensor designed for detecting breast cancer type 1 (BRCA1) gene mutations. The biosensor integrates graphene nanosheets (Graph-NS), tetrahedral DNA nanostructures (TDNs), and carbon nanodots (CNDs) to enhance sensitivity and specificity. Graph-NS are employed to structure the transducer and serve as a platform for DNA immobilization. TDNs are engineered with a BRCA1 gene-specific capture probe located at the apex (TDN-BRCA1), facilitating efficient biorecognition. Additionally, the basal vertices of TDNs are functionalized with amino groups, enabling their attachment to the CSPE/Graph-NS surface via amino-graphene interaction. This platform effectively identifies single-base mutations in the BRCA1 gene utilizing synthesized CNDs as a coreactant and [Ru(bpy)3]2+ as the luminophore through the coreactant pathway. The developed biosensor demonstrates exceptional sensitivity and can detect a single mutation in the BRCA1 gene. Furthermore, it has been successfully validated in real samples obtained from breast cancer patients, showcasing a remarkable detection limit of 1.41 aM.

Nanocellulose-based functional materials towards water treatment

Water resources are important ecological resources for human survival. To date, advanced water purification technology has become one of the focus of global attention due to the continuous deterioration of the environment and the serious shortage of freshwater resources. Recently, nanocellulose, as a kind of sustainable and carbon-neutral biopolymer, has not only the properties of cellulose, but also the important nature of nanomaterials, including large specific surface area, tailorable surface chemistry, excellent mechanical flexibility, biodegradability, and environmental compatibility. Herein, this review covers several methods of extraction and preparation of nanocellulose and the functional modification strategies. Subsequently, we systematically review the application and latest research progress of nanocellulose-based functional material towards water treatment, from micro/nanoparticles filtration, dyes/organics adsorption/degradation, heavy metal ions adsorption/detection and oil-water separation to seawater desalination. Furthermore, scalable and low-cost nanocellulose synthesis strategies are discussed. Finally, the challenges and opportunities of nanocellulose water purification substrate in industrial application and emerging directions are briefly discussed. This review is expected to provide new insights for the application of advanced functional materials based on nanocellulose in water treatment and environmental remediation, and promote rapid cross-disciplinary development.

Comprehensive review of protein imaging with AIEgens conjugated probes: From concentration to conformation

Proteins are an essential component of living organisms, and the study of their structure and function is of great importance in biological and medical research. In recent years, the remarkable phenomenon of aggregation-induced emission (AIE) has been extensively utilized in protein detection. Significant progress has been made in the development of aggregation-induced emission luminogens (AIEgens), which have proven invaluable in protein imaging. This review highlights AIEgen-conjugated probes for imaging proteins in tumor cells through various mechanisms, including physical interactions, ligand binding, and enzymatic cleavage. These probes exploit the AIE effect to enhance the signal-to-noise ratio, providing important tools for protein research. Additionally, these probes can be used to study structural changes in intracellular protein phase separation processes, such as unfolded, misfolded, fibrous, and amorphous aggregates. The above research achievements presented lay the foundation for the widespread application of AIEgen-conjugated probes in the biomedical field and are expected to stimulate further development in related research.

Functional, structural, and rheological properties of the complexes containing sunflower petal extract with dairy and plant-based proteins

This study aims to investigate the impact of sunflower petal extract (SFE) on the functional and structural properties of sodium caseinate and chickpea proteins. For this purpose, 3.5 % of sodium caseinate solution and 3.5 % of protein extracted from chickpea powder were prepared in phosphate buffer (pH = 7). SFE was used at different concentrations, from 1 to 3 % in different protein solutions and functional, structural and rheological properties were measured. The results revealed that complexation of SFE with different proteins can enhance the antioxidant, foaming properties, solubility, emulsion activity, emulsion stability, viscoelastic behavior, and can decrease surface hydrophobicity. FTIR and docking results showed that the most bonding type was non-covalent bonds. Major phenolic compounds containing heliannone A, B, and kaempferol had strong affinity with sodium caseinate, and then chickpea protein. Therefore, the results demonstrated that SFE and its complexes had appropriate emulsifying properties that reduces interfacial tension in the water/oil interface.

a-SiC heteromorphic immersion nanocavities enabling wide-field real-time single-molecule detection

Real-time single-molecule detection via fluorescence exhibits advantages of non-contact and specificity, especially in illustrating the dynamic heterogeneity of living substances. However, wide-field view and signal-to-noise ratio (SNR) are always contradictory in real-time single-molecule detection with fluorescence labels, owing to the limitation of the omnidirectional radiation characteristics of fluorophores. Herein, we propose a nano optical sensing device based on a-SiC heteromorphic immersion nanocavities (aHINCs), enabling wide-field real-time single-molecule imaging without sacrificing SNR. The characteristics of architectural aHINCs for far-field imaging are investigated, and the designed sensing device help adjust the emission direction of fluorescence in gold hot spots of nanocavities, allowing the fluorescence divergence angle to be adjusted to ±10°. The experimental results show the SNR reached 22, markedly strengthening the fluorescence collection efficiency. The simultaneous observation of nanocavity sites, within the same field of view of the chip, is 488 times the number of sites observed with classic detection method. Furthermore, the wide-field real-time detection of the single molecule-specific binding process of the oligo DNA complementary chain is successfully realized. The nano optical sensing device based on the aHINC shows potential for parallel real-time single-molecule detection applications.

Modulating room temperature phosphorescence of acrylamide by stepwise rigidification for its detection in potato crisps

The selective detection of acrylamide (AA) is crucial, which is limited by the high background and interferences from food matrix. A room temperature phosphorescence (RTP) assay was developed through modulating its RTP by a stepwise rigidification strategy. The first step rigidification resulted in crosslinking of AA and denser of hydrogen bonding. This prompted the RTP efficiency from <0.1 to 3.8 % and emission lifetime of AA (from 3.0 μs to 0.29 s). Introducing boric acid resulted in the second step rigidification, triggered the formation of rigid matrix and chemical bonding. These synergistic effects prompted the photoluminescence quantum yield to 23.7 % and emission lifetime to 1.20 s. AA was quantitatively detected through monitoring the RTP intensity, with a limit of detection of 0.9 μg/mL. Benefiting from the delayed signal detection, background signal and the interferences from food matrices were eliminated, endowing the detection of AA in practical food samples.

Novel self-assembled spirochiral nanofluorescent probe for fipronil detection efficiently by PET mechanism

A novel spirochiral compound S-SPINOL-Y1 (S-6,6'-bis (thiophen-2-yl)-2,2', 3,3'-tetrahydro-1,1'-spirobis[indinee]-7,7'-diol) was synthesized via a Suzuki reaction and self-assembled into nanospheres in ethanol solution. Nano or micron vesicles could be formed by changing the concentration of ethanol solvent. The resulting nanoprobe demonstrated rapid and effective recognition of fipronil (FIP) through the photoinduced electron transfer effect (PET mechanism), as evidenced by complete fluorescence quenching. Concurrently, the spiral chiral S-SPINOL-Y1 and FIP co-assembled into vein-like nanotubes within the ethanol solution by covalent bonding and intermolecular hydrogen bonding.

One-step construction of bioinspired multi-enzyme mimicking nanozyme as a universal platform for multi-mode sensing and catalytic degradation

Nanozymes, a category of nanomaterials with exceptional enzyme-like activity, exhibit the significant promise to overcome the inherent limitations of natural enzymes. Inspired by the active site structure of natural laccase, a biomimetic MA-Cu nanozyme with three-dimensional network structure was constructed in water system through one-step complexation based on the specific coordination between nitrogen-rich triazine heterocyclic melamine and Cu2+, in a facile, green and economical manner. Compared to natural laccase, MA-Cu possesses superior multi-enzyme mimicking activity, stability and cost-effectiveness. Through comprehensive characterizations, activity tests and theoretical calculations, the catalytic mechanism and the ligand-tunability of enzyme-like activity have been thoroughly investigated. Based on its multi-enzyme-like activities, a multifunctional monitoring platform for sulfide in food, epinephrine in preparations and glutathione in cells was successfully constructed, respectively. Notably, a green degradation and discrimination platform based on MA-Cu for various pollutants was developed, exhibiting distinguished substrate universality and detoxication capacity. As a stable, easily scalable and commercially applicable nanozyme, MA-Cu is expected to become a compelling candidate for replacing natural enzyme, showing excellent prospects in environmental remediation and biosensing.

New near-infrared fluorescent probe for imaging superoxide anion of cell membrane

Selective imaging of superoxide anion is important for understanding its role in cell membrane biology, but is often a challenging task because of the lack of an effective fluorescence probe. In this study, a new near-infrared fluorescent probe (SHX-O) that can target cell membrane was developed for imaging superoxide anion. SHX-O was designed by simultaneously incorporating a sulfonated bis-indole and a diphenylphosphinyl recognition group into the hemicyanine moiety. The probe itself showed a rather weak fluorescence due to the hemicyanine's hydroxyl substitution; however, its reaction with superoxide anion caused a large enhancement of near-infrared fluorescence at 790 nm. Moreover, SHX-O exhibited not only high selectivity for superoxide anion over other reactive oxygen species, but also specific cell membrane localization, which may be attributed to the probe's amphiphilic structure. Using the probe, fluorescence imaging of cell membrane superoxide anion produced in the presence of xanthine oxidase and xanthine has been achieved in living cells. We believe that SHX-O may serve as a potential tool for imaging and investigating superoxide anion of cell membrane.

Aggregation-induced emission (AIE) of Au(I)-GSH complexes activated by cationic polymer for sensitive foodborne pathogens detection and inactivation

Aggregation-induced emission (AIE) is a novel signal output method but is limited in pathogen sensing. Herein, a multifunctional biosensor based on the AIE properties of Au(I)-GSH complexes as signal conversion tags was firstly constructed for rapid and sensitive total bacteria. Bacteria were captured by the boronic acid group of MNPs@Au@4-MPBA (MAu@MPBA) through recognition of peptidoglycan on their surface. Simultaneously, cationic polymer Poly (diallyldimethylammonium chloride) (PDDA) were electrostatic absorb on bacteria. After magnetic separation, the remaining PDDA induced Au(I)-GSH complexes aggregation to produce strong red fluorescence, which was linearly with the quantity of bacteria. Under optimized conditions, quantitative detection of bacteria can be achieved within 60 min, with a minimum detection concentration of 18 CFU/mL. Moreover, 90 % bacteria can be effectively inactivated while being detected. This strategy is capable of sensitively detecting and killing foodborne pathogens and can be successfully applied to food safety monitoring.

Influence of terminal moiety on PCE of DSSCs: An In Silico study based on triazatruxene-benzothiadiazole dye

Our study utilized an experimentally synthesized dye as a reference molecule, employing a donor-π linker-acceptor (D-π-A) framework for organic solar cells. The molecule featured a triazatruxene group linked with alkyl branches as the donor and ethynyl benzoic acid as the acceptor, connected through a derivative of benzothiadiazole as the π linker. To improve optoelectronic and photovoltaic properties, ten theoretically designed dyes (ZA1-ZA10) are proposed, differing from the reference (R) by modifying the terminal acceptor moiety. Various quantum analyses, including frontier molecular orbitals, optical properties, reorganization energies, binding energies, transition density matrices (TDM), molecular electrostatic potential (MEP), dipole moment, and density of states were carried out at DFT/B3LYP/6-31G(d,p). Ground state geometries revealed a co-planar morphology in ZA1-ZA10, facilitating efficient charge transportation. TDM and MEP illustrated improved electronic transitions in the excited states. Computational analyses revealed superior photovoltaic properties of ZA1-ZA10. Notably, ZA5 exhibited the most significant redshift (1021 nm) in absorption, lowest bandgap (1.44 eV), smallest transition energy (1.21 eV), least binding energy (0.23 eV), and improved charge mobilities. Results from the adsorption of ZA1-ZA10 on the TiO2 layer confirmed their anchoring potential and effective injection of electrons to anatase (TiO2)9. These significant outcomes promise the potential and novelty of our designed dyes for higher power conversion efficiencies (PCE) in dye-sensitized solar cells (DSSCs).

Theoretical investigation on the surrounding effects of second-order nonlinear properties for (N^C^N)Pt(II)Cl complexes

Pt(II) complexes are widely used as nonlinear optical (NLO) materials. The geometric and electronic structures, second-order NLO property and UV-Vis absorption spectra of (N^C^N)Pt(II)Cl complexes (1-4) N^C^N binding by central benzene and two lateral N-heterocycles) are evaluated by density functional theory (DFT) and time-dependent DFT calculations. The detailed environmental effect of total first hyperpolarizability (βtot) in the solution and crystal phases is simulated by polarized continuum model (PCM) and quantum mechanics/molecular mechanics (QM/MM) method, respectively. The results highlight that the complex 3 exhibits largest βtot value in the gas, solution and crystal phases which can be attributed to the higher electron π-delocalization of ligands. Further, an evident red shift towards longer wavelength is observed for the complex 3. The origin of larger βtot value can be reasonably interpreted by the two-level model. In addition, the surrounding exerts an important influence on modulating second-order NLO properties. The solvent effect results in the larger βtot value than that of gas phase. The intermolecular interaction plays an important role in crystal phase. The formation of dimer can reduce the βtot value in comparison with the βtot value of the monomer in the crystal phase, because the centrosymmetric configuration of dimer implies a decrease of dipole moment (μ) in contrast to the large μ value of monomer. It is expected that this work will provide some guidance for designing Pt(II) NLO materials.

Relationship between antioxidant activity and ESIPT process based on flavonoid derivatives: A comprehensive analysis

Antioxidant activity, as a topic of current interest, is discussed together with the excited state intramolecular proton transfer (ESIPT) process for three flavonoid derivatives, based on density functional theory (DFT)and time-dependent DFT (TD-DFT) methods, as well as DPPH free radical scavenging assay. The potential energy curves and transition states demonstrate that the three molecules can undergo only single proton transfer in the excited state, and all of them are ultrafast ESIPT processes. The absorption spectra of all the molecules show effective protection against UV radiation with low fluorescence intensity, especially Baicalein (Bai), which demonstrates their great potential for sunscreen applications. The density of states, HOMO energy values, global and local indices reveal that the antioxidant activity of the molecules after ESIPT process is enhanced, with Bai having the highest antioxidant activity, which is significantly attributed to the number and position of phenolic hydroxyl groups. Moreover, by comparing the DPPH free radical scavenging activity under the dark and UV radiation conditions, the radical scavenging activity (RSA) value in the UV radiation is remarkably higher than that in the dark condition, in which Bai achieves RSA value of 93.4%. Overall, the antioxidant activity of all three ESIPT-based flavonoid derivatives, especially Bai, is significantly elevated in the keto* form, which reinforces the significant relationship between antioxidant activity and ESIPT process, and provides new application prospects for molecules with ESIPT properties.

Digital SERS immunoassay of Interleukin-6 based on Au@Ag-Au nanotags

Interleukin-6 (IL-6) is a crucial cytokine involved in inflammation and immune regulation. However, the detection of IL-6 with ultrasensitivity and high specificity remains a significant challenge due to the inherent complexity of biofluids. Herein, we present a digital surface enhanced Raman scattering (SERS) immunoassay using core-shell Au@Ag-Au nanotags for IL-6 detection with ultrasensitivity and high reliability. A low-cost silicon chip was functionalized as capture substrates, employing novel SERS nanotags that exhibit strong, robust and reproducible signals at single-nanoparticle resolution as the amplification element. We proposed two analytical methods to validate single-molecule events follow a Poisson distribution and to quantify protein biomarkers over a broad linear dynamic range, respectively. The strong alignment between theoretical and experimental results enhances the method's reliability. Our assay provides two readouts: colorimetric analysis by naked eyes for high concentrations (>1 ng/mL) and digital SERS analysis for low concentrations. Following method optimization, we obtained a linear range from 100 fg/mL to 1 ng/mL (R2 = 0.994) with a limit of detection (LOD) of 12.4 fg/mL, suitable for clinical applications. The method was tested for IL-6 quantification in healthy human serum and saliva, with recoveries from 92.4% to 105.3%. Finally, the immunoassay demonstrated strong consistency with the standard clinical laboratory method when tested with clinical serum samples. Thus, our proposed the digital SERS immunoassay is a promising tool for the precision clinical diagnosis of IL-6-related diseases or other conditions.

Detection of human salivary stress biomarkers using an easy-to-use array sensor based on fluorescent organic molecules

During stressful conditions, the human body synthesizes catecholamine neurotransmitters such as dopamine and adrenaline, and cortisol. The monitoring of these three molecules levels is crucial for stress management and holds significant medical applications. Here we developed an analytical device that incorporates a biomimetic (tongue-mimic) associated with an optical physico-chemical transducer, able to detect simultaneously cortisol, dopamine and adrenaline in human saliva without pre-treatments, using an array sensor based on fluorescent chemical receptors (BODIPY, Rhodamine, and Naphthylamides) able to interact by non-covalent interaction with cortisol, adrenaline and dopamine, leading to a change of the emission. Calibration, recovery and selectivity have been performed to validate the device. In particular, the linear responses of the array to concentration range of 1 pM-1 mM of the three analytes were demonstrated by PLS analysis, as well as the high selectivity by PLS-DA analysis performed with artificial saliva samples. Analyses in real human saliva samples, compared to the validated analytical methods, demonstrated that our prototype represents the first point-of-care device able to quantify these three analytes in human saliva with one single analysis in a wider concentration range respect to the other standard methods.