Evaluation of the Multidimensional Enhanced Lateral Flow Immunoassay in Point-of-Care Nanosensors.

Point-of-care (POC) nanosensors with high screening efficiency show promise for user-friendly manipulation in the ever-increasing on-site analysis demand for illness diagnosis, environmental monitoring, and food safety. Currently, inspired by the merits of integrating advanced nanomaterials, molecular biology, machine learning, and artificial intelligence, lateral flow immunoassay (LFIA)-based POC nanosensors have been devoted to satisfying the commercial demands in terms of sensitivity, specificity, and practicality. Herein, we examine the use of multidimensional enhanced LFIA in various fields over the past two decades, focusing on introducing advanced nanomaterials to improve the acquisition capability of small order of magnitude targets through engineering transformations and emphasizing interdomain fusion to collaboratively address the inherent challenges in current commercial applications, such as multiplexing, development of detectors for quantitative analysis, more practical on-site monitoring, and sensitivity enhancement. Specifically, this comprehensive review encompasses the latest advances in comprehending LFIA with an alternative signal transduction pattern, aiming to achieve rapid, ultrasensitive, and "sample-to-answer" available options with progressive applications for POC nanosensors. In summary, through the cross-collaboration development of disciplines, LFIA has the potential to break the barriers toward commercialization and achieve laboratory-level POC nanosensors, thus leading to the emergence of the next generation of LFIA.

Advances of biomacromolecule-based antibacterial hydrogels and their performance evaluation for wound healing: A review.

Biomacromolecule hydrogels possess excellent mechanical properties and biocompatibility, but their inability to combat bacteria restricts their application in the biomedical field. With the increasing requirements and demands for hydrogel dressings, wound dressings with antibacterial properties of biomacromolecule hydrogels reinforced by adding antibacterial agents have attracted much attention, and related reviews are emerging. In this paper, the advances of biomacromolecule antibacterial hydrogels (including chitosan, sodium alginate, Hyaluronic acid, cellulose and gelatin) were first overviewed, and the antibacterial agents incorporated into hydrogels were classified (including metals and their derivatives, carbon-based materials, and native compounds). A series of performance evaluations of antibacterial hydrogels in the process of promoting wound healing were then reviewed, including basic properties (mechanical, rheological, injectable and self-healing, etc.), in vitro experiments (hemostasis, antibacterial, anti-inflammatory, anti-oxidation, biocompatibility) and in vivo experiments (in vivo model, histomorphology analysis, cytokines). Finally, the future development of biomacromolecule-based antibacterial hydrogels for wound healing is prospected. This work can provide a useful reference for researchers to prepare practical new wound hydrogel dressings.

Single-Cell Transcriptomic Analysis Reveals Dynamic Cellular Processes in Corneal Epithelium During Wound Healing in Cynomolgus Monkeys.

Purpose: Corneal wounding healing is critical for maintaining clear vision, however, a complete understanding of its dynamic regulatory mechanisms remains elusive. Here, we used single-cell RNA sequencing (scRNA-seq) to analyze the cellular activities and transcriptional changes of corneal limbal epithelial cells at different stages after wound healing in cynomolgus monkeys, which exhibit a closer transcriptomic similarity to humans. Methods: Corneal limbal tissues were collected during uninjured, 1-day and 3-day healing stages, dissociated into single cells, and subjected to scRNA-seq using the 10× Genomics platform. Cell types were clustered by graph-based visualization methods and unbiased computational analysis. Additionally, cell migration assays and immunofluorescent staining were performed on cultured human corneal epithelial cells. Results: We characterized nine cell clusters by scRNA-seq analysis of the cynomolgus monkey corneal epithelium. By comparing heterogeneous transcriptional changes in major cell types during corneal healing, we highlighted the importance of limbal epithelial cells (LEPCs) and basal epithelial cells (BEPCs) in extracellular matrix (ECM) formation and wound healing, as well as suprabasal epithelial cells (SEPCs) in epithelial differentiation during the healing processes. We further identified five different sub-clusters in LEPC, including the transit amplifying cell (TAC) sub-cluster that promotes early healing through the activation of thrombospondin-1 (THBS1) expression. Conclusions: Our study represents the first comprehensive exploration of the detailed transcriptome profile of individual corneal cells during the wound healing process in nonhuman primates. We demonstrate the intricate mechanisms involved in corneal healing and provide a promising avenue for potential therapies in corneal wound healing.

Polycaprolactone/gelatin/ZIF-8 nanofiber membrane for advanced guided tissue regeneration in periodontal therapy.

The periodontal tissue regeneration strategy based on guided tissue regeneration (GTR) membranes is an effective therapy for periodontal defects. Traditional GTR membranes, however, primarily serve as physical barriers and lack antimicrobial and osteogenic functions. Herein, we developed a multifunctional nanofiber membrane with zeolitic imidazolate framework-8 nanoparticles (ZIF-8 NPs) loaded in a hydrophilic gelatin layer. The release of Zn2+ from the ZIF-8 NPs effectively promoted bone tissue repair and simultaneously enabled GTR membranes with >99 % antibacterial efficacies against Escherichia coli and Staphylococcus aureus. Additionally, the incorporation of gelatin enhances cellular adhesion and growth. Furthermore, in vivo studies revealed significant bone regeneration, with increased trabecular number and reduced separation. Owing to its multiple functions, excellent biocompatibility and desirable mechanical properties, this membrane has considerable potential in the field of periodontal therapy.

Asymmetric Nanobowl Confinement-Engineered "Plasmonic Storms" for Machine Learning-Assisted Ultrasensitive Immunochromatographic Assay of Pathogens.

Efficient field enhancement effects through plasmonic chemistry for ultrasensitive biosensing still face a great challenge. Herein, nanoconfinement engineering accumulation and synergistic effects are used to develop a "plasmonic storms" strategy with a high field enhancement effect, and gold nanoparticles (AuNPs) are used as active sites for a proof of concept because of their distinctive localized surface plasmon resonance and neighborly coupled electromagnetic field. Briefly, a large number of AuNPs are selectively and accurately stacked in the confined nanocavity of the bowl-like nanostructure through an in situ-synthesized strategy, which provides a space for strong coupling of electromagnetic fields between these adjacent AuNPs, forming "plasmonic storms" with an enhanced field that is 3 orders of magnitude higher than that of free AuNPs. The proposed nanoconfinement-engineered "plasmonic storms" are demonstrated by surface-enhanced Raman scattering (SERS) and photothermal experiments and theoretically visualized by finite element simulation. Finally, the proposed "plasmonic storms" are used for enhanced colorimetric/SERS/photothermal immunochromatographic assay to detect Salmonella typhimurium with the help of a machine learning algorithm, achieving a low limit of detection of 142 CFU mL-1, highlighting the potential of nanoconfinement in biosensing.

Unlocking the potential: How acupuncture reshapes the liver-centered lipid metabolism pattern to fight obesity.

Obesity, a widespread global health issue, is frequently linked to disrupted lipid metabolism, resulting in excessive accumulation of adipose tissue and associated health complications. Acupuncture, a traditional Chinese medical modality, has exhibited potential as a viable intervention for addressing obesity. The underlying mechanism proposed involves the stimulation of specific acupoints to exert a regulatory influence on hepatic function. The liver has a central role in lipid metabolism, including processes such as lipid synthesis, storage and distribution. Acupuncture is believed to enhance the liver's efficiency in processing lipids, thereby reducing lipid accumulation and improving metabolic functions. Research indicates that acupuncture can influence the expression of certain genes and proteins involved in lipid metabolism in the liver. This includes upregulating genes that promote lipid breakdown and oxidation, and downregulating those involved in lipid synthesis. Additionally, acupuncture has been shown to improve insulin sensitivity, which is crucial for the regulation of lipid metabolism. Furthermore, the potential anti-inflammatory effects of acupuncture may play a significant role in its efficacy for the treatment of obesity. The presence of chronic inflammation has been strongly associated with metabolic disorders such as obesity. Through its ability to mitigate inflammation, acupuncture can potentially aid in the restoration of lipid metabolism and the reduction of body weight. Moreover, the amelioration of hepatic oxidative stress represents another mechanism by which acupuncture may contribute to the reduction of lipid deposition. Notably, the liver, being the primary site of lipid metabolism, maintains communication with various organs including the brain, adipose tissue, skeletal muscle and intestines. This perspective opens new avenues for the treatment of obesity, emphasizing the importance of holistic approaches in managing complex metabolic disorders. Please cite this article as: Yang SR, Chen L, Luo D, Wang YY, Liang FX. Unlocking the potential: How acupuncture reshapes the liver-centered lipid metabolism pattern to fight obesity. J Integr Med. 2024; 22(5): 523-532.

Phospholipid peroxidation in macrophage confers tumor resistance by suppressing phagocytic capability towards ferroptotic cells.

Ferroptosis holds significant potential for application in cancer therapy. However, ferroptosis inducers are not cell-specific and can cause phospholipid peroxidation in both tumor and non-tumor cells. This limitation greatly restricts the use of ferroptosis therapy as a safe and effective anticancer strategy. Our previous study demonstrated that macrophages can engulf ferroptotic cells through Toll-like receptor 2 (TLR2). Despite this advancement, the precise mechanism by which phospholipid peroxidation in macrophages affects their phagocytotic capability during treatment of tumors with ferroptotic agents is still unknown. Here, we utilized flow sorting combined with redox phospholipidomics to determine that phospholipid peroxidation in tumor microenvironment (TME) macrophages impaired the macrophages ability to eliminate ferroptotic tumor cells by phagocytosis, ultimately fostering tumor resistance to ferroptosis therapy. Mechanistically, the accumulation of phospholipid peroxidation in the macrophage endoplasmic reticulum (ER) repressed TLR2 trafficking to the plasma membrane and caused its retention in the ER by disrupting the interaction between TLR2 and its chaperone CNPY3. Subsequently, this ER-retained TLR2 recruited E3 ligase MARCH6 and initiated the proteasome-dependent degradation. Using redox phospholipidomics, we identified 1-steaoryl-2-15-HpETE-sn-glycero-3-phosphatidylethanolamine (SAPE-OOH) as the crucial mediator of these effects. Conclusively, our discovery elucidates a novel molecular mechanism underlying macrophage phospholipid peroxidation-induced tumor resistance to ferroptosis therapy and highlights the TLR2-MARCH6 axis as a potential therapeutic target for cancer therapy.

Enzymatic synthesis of N-formylated sialosides via a five-enzyme cascade.

Here we report an enzymatic approach to synthesize N-formylneuraminic acid (Neu5Fo) containing sialosides, through a five-enzyme cascade. This method stands as an alternative to traditional chemical syntheses, aiming for precision and efficiency in generating sialosides with a tailored N-formyl group generated directly from formic acid. The newly synthesized Neu5Fo was characterized using various NMR techniques revealing a conformational equilibrium at the amide bond of the formyl group in slow exchange on the NMR time scale with a trans : cis ratio of ∼2 : 1. This work not only suggests potential for exploring the biological roles of sialosides but also points to the possibility of developing novel therapeutic agents.

Ionic liquid-integrated aqueous electrolyte regulation on solvation chemistry and electrode interface for reversible dendrite-free zinc anodes.

Zn anodes suffer from poor reversibility and stability owing to nonuniform dendrite growth and self-corrosion. Here, 1-ethyl-3-methylimidazolium acetate (EMImAc) is introduced to reconstruct interfacial electrical double layer with simultaneously manipulating the solvation environment and the adsorption situation on Zn anode. The acetate anions with high nucleophilicity can effectively alter the solvation shell around Zn2+ ions and immobilize the H2O molecules, thus weakening water activity and alleviating water-related parasitic reactions. Concomitantly, both the imidazolium cation and acetate anion are inclined to gather on Zn anode surface for constructing an electrostatic shielding layer, and meanwhile the chemisorbed acetate anions also contribute to accelerate the Zn(H2O)62+ desolvation process. Such a synergistic effect enables uniform electric field distribution and facilitates Zn ion flux, which mitigates the random diffusion of Zn2+ and finally promotes the dendrite-free deposition. As a result, the Zn/Zn symmetric cells with EMImAc-integrated aqueous electrolyte realize an excellent cycling lifespan of 7000 h (0.5 mA cm-2/0.25 mAh cm-2) and high Zn utilization of 61.3 % (15 mA cm-2/20 mAh cm-2). Furthermore, the effective of EMImAc additive is demonstrated in Zn/V2O5 cells. This work offers insights into the ionic liquid-integrated aqueous electrolytes to enhance the interface stability of Zn anode for rechargeable zinc batteries.

Potential treatment of glutathione in bullfrogs with abnormal hepatic lipid metabolism revealed by hepatic lipid metabolism and serum metabolomics analysis.

Introduction: With the continuous growth of bullfrog supply, it has become an important aquaculture species. Due to the lack of actionable industry standards and regulation, the misuse of anti-disease drugs and abnormal liver lipid metabolism in bullfrogs have become a major obstacle to the development of bullfrog aquaculture industry. Glutathione is a natural tripeptide that can be synthesized intracellularly, and its physiological functions mainly include the treatment of liver diseases, antioxidant, detoxification, anti-tumor, enhancement of immunity, and delaying aging. Methods: In this study, the therapeutic effect of glutathione on bullfrogs with abnormal liver lipid metabolism was revealed from hepatic lipid metabolism and serum metabolomics analysis. The survival rate, liver histomorphology, serum antioxidant enzyme activity, liver lipase activity and serum metabolomics, liver metabolomics were studied and analyzed by feeding the bullfrogs with abnormal lipid metabolism with glutathione for 20 days in the NC, FI and GSH groups. Results: The results of the study showed that glutathione was able to repair the liver and improve the survival rate of bullfrogs with abnormal lipid metabolism; the activity of serum SOD enzymes was significantly increased; the activities of ACP and AKP were significantly decreased; the activities of HDL-C and T-CHO were significantly increased; and the activities of LDL-C, TBA, and TG were significantly decreased in the liver; the contents of metabolites, such as PC, PS, and PE were significantly up-regulated, and the levels of up-regulated Autophagy - other, Necroptosis and ErbB signaling pathway, and down-regulated Sphingolipid metabolism, D-Amino acid metabolism metabolic pathway, to some extent The metabolic pathways of Sphingolipid metabolism and D-Amino acid metabolism were down-regulated to alleviate the disorders of glycerophospholipid and amino acid metabolism to a certain extent, thus alleviating the abnormalities of liver lipid metabolism. Discussion: The results showed that glutathione could effectively treat the liver lipid metabolism disorder of bullfrogs, promote the growth and development of bullfrogs, repair the liver function, reduce the inflammation, and promote the healthy and green development of bullfrog industry.

Trends in HIV/AIDS-Related Mortality and the Impact of Antiretroviral Treatment Strategies in Lu'an City: A Comprehensive Analysis.

BACKGROUND There are many factors that affect human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS)-related deaths, and different antiretroviral therapy (ART) strategies may affect HIV/AIDS-related fatality rates. However, studies on this area are very limited. This study aimed to evaluate the factors associated with HIV/AIDS-related mortality and the impact of different ART strategies in Lu'an City, Anhui Province, China, 1999-2023. MATERIAL AND METHODS Data of HIV/AIDS cases were downloaded from the China HIV/AIDS Comprehensive Response Information Management System, and were assessed to evaluate the impact of different ART strategies on the related fatality rate using interrupted time series (ITS). RESULTS We found that age at diagnosis of 15 years, 25 years, 40 years, and 60 years, as well as receiving ART, were protective factors against death (with P below 0.05), while lower CD4 count at the last CD4 count and the year of diagnosis before 2007 and between 2007 and 2016 were risk factors (with P below 0.05). ITS analysis revealed that in the year of the introduction of free ART in 2006, the fatality rate decreased by 38.60% (P=0.015). The fatality rate trend from 2006 to 2015 was -1.1%, which was not statistically significant (P=0.434). The fatality rate trend from 2016 to 2023 was -0.33%, indicating a decreasing trend (P=0.000). CONCLUSIONS Children under 15 years old and elderly patients had a higher risk of death. The main reasons for the decrease in HIV/AIDS-related fatality rate were ART, especially the "early treatment" strategy.

H2Se-evolving bio-heterojunctions promote cutaneous regeneration in infected wounds by inhibiting excessive cellular senescence.

Pathogenic infection leads to excessive senescent cell accumulation and stagnation of wound healing. To address these issues, we devise and develop a hydrogen selenide (H2Se)-evolving bio-heterojunction (bio-HJ) composed of graphene oxide (GO) and FeSe2 to deracinate bacterial infection, suppress cellular senescence and remedy recalcitrant infected wounds. Excited by near-infrared (NIR) laser, the bio-HJ exerts desired photothermal and photodynamic effects, resulting in rapid disinfection. The crafted bio-HJ could also evolve gaseous H2Se to inhibit cellular senescence and dampen inflammation. Mechanism studies reveal the anti-senescence effects of H2Se-evolving bio-HJ are mediated by selenium pathway and glutathione peroxidase 1 (GPX1). More critically, in vivo experiments authenticate that the H2Se-evolving bio-HJ could inhibit cellular senescence and potentiate wound regeneration in rats. As envisioned, our work not only furnishes the novel gasotransmitter-delivering bio-HJ for chronic infected wounds, but also gets insight into the development of anti-senescence biomaterials.

Thymol Induces Fenton-Reaction-Dependent Ferroptosis in Vibrio parahemolyticus.

Thymol has efficient bactericidal activity against a variety of pathogenic bacteria, but the bactericidal mechanism against Vibrio parahemolyticus (V. parahemolyticus) has rarely been reported. In the current study, we investigated the bactericidal mechanism of thymol against V. parahemolyticus. The Results revealed that 150 µg/mL of thymol had 99.9% bactericidal activity on V. parahemolyticus. Intracellular bursts of reactive oxygen species (ROS), Fe2+accumulation, lipid peroxidation, and DNA breakage were checked by cell staining. The exogenous addition of H2O2 and catalase promoted and alleviated thymol-induced cell death to a certain extent, respectively, and the addition of the ferroptosis inhibitor Liproxstatin-1 also alleviated thymol-induced cell death, confirming that thymol induced Fenton-reaction-dependent ferroptosis in V. parahemolyticus. Proteomic analysis revealed that relevant proteins involved in ROS production, lipid peroxidation accumulation, and DNA repair were significantly upregulated after thymol treatment. Molecular docking revealed two potential binding sites (amino acids 46H and 42F) between thymol and ferritin, and thymol could promote the release of Fe2+ from ferritin proteins through in vitro interactions analyzed. Therefore, we hypothesized that ferritin as a potential target may mediate thymol-induced ferroptosis in V. parahemolyticus. This study provides new ideas for the development of natural inhibitors for controlling V. parahemolyticus in aquatic products.

Cyanomethylquinolones as a New Class of Potential Multitargeting Broad-Spectrum Antibacterial Agents.

This work identified a class of cyanomethylquinolones (CQs) and their carboxyl analogues as potential multitargeting antibacterial candidates. Most of the prepared compounds showed high antibacterial activities against most of the tested bacteria, exhibiting lower MIC values (0.125-2 µg/mL) than those of clinical norfloxacin, ciprofloxacin, and clinafloxacin. The low hemolysis, drug resistance, and cytotoxicity, as well as good predictive pharmacokinetics of active CQs and carboxyl analogues revealed their development potential. Furthermore, they could eradicate the established biofilm, facilitating bacterial exposure to these antibacterial candidates. These active compounds could induce bacterial death through multitargeting effects, including intercalating into DNA, up-regulating reactive oxygen species, damaging membranes directly, and impeding metabolism. Moreover, the highly active cyclopropyl CQ 15 exhibited more effective in vivo anti-MRSA potency than ciprofloxacin. These findings highlight the potential of CQs and their carboxyl analogues as multitargeting broad-spectrum antibacterial candidates for treating intractable bacterial infections.

Expert consensus on pediatric orthodontic therapies of malocclusions in children.

Malocclusion, identified by the World Health Organization (WHO) as one of three major oral diseases, profoundly impacts the dental-maxillofacial functions, facial esthetics, and long-term development of ~260 million children in China. Beyond its physical manifestations, malocclusion also significantly influences the psycho-social well-being of these children. Timely intervention in malocclusion can foster an environment conducive to dental-maxillofacial development and substantially decrease the incidence of malocclusion or reduce the severity and complexity of malocclusion in the permanent dentition, by mitigating the negative impact of abnormal environmental influences on the growth. Early orthodontic treatment encompasses accurate identification and treatment of dental and maxillofacial morphological and functional abnormalities during various stages of dental-maxillofacial development, ranging from fetal stages to the early permanent dentition phase. From an economic and societal standpoint, the urgency for effective early orthodontic treatments for malocclusions in childhood cannot be overstated, underlining its profound practical and social importance. This consensus paper discusses the characteristics and the detrimental effects of malocclusion in children, emphasizing critical need for early treatment. It elaborates on corresponding core principles and fundamental approaches in early orthodontics, proposing comprehensive guidance for preventive and interceptive orthodontic treatment, serving as a reference for clinicians engaged in early orthodontic treatment.

Dual-plasmonic CuS@Au heterojunctions synergistic enhanced photothermal and colorimetric dual signal for sensitive multiplexed LFIA.

Multiplexed immunodetection, which achieves qualitative and quantitative outcomes for multiple targets in a single-run process, provides more sufficient results to guarantee food safety. Especially, lateral flow immunoassay (LFIA), with the ability to offer multiple test lines for analytes and one control line for verification, is a forceful candidate in multiplexed immunodetection. Nevertheless, given that single-signal mode is incredibly vulnerable to interference, further efforts should be engrossed on the combination of multiplexed immunodetection and multiple signals. Photothermal signal has sparked significant excitement in designing immunosensors. In this work, by optimizing and comparing the amount of gold, CuS@Au heterojunctions (CuS@Au HJ) were synthesized. The dual-plasmonic metal-semiconductor hybrid heterojunction exhibits a synergistic photothermal performance by increasing light absorption and encouraging interfacial electron transfer. Meanwhile, the colorimetric property is synergistic enhanced, which is conducive to reduce the consumption of antibodies and then improve assay sensitivity. Therefore, CuS@Au HJ are suitable to be constructed in a dual signal and multiplexed LFIA (DSM-LFIA). T-2 toxin and deoxynivalenol (DON) were used as model targets for the simulated multiplex immunoassay. In contrast to colloidal gold-based immunoassay, the built-in sensor has increased sensitivity by ≈ 4.42 times (colorimetric mode) and ≈17.79 times (photothermal mode) for DON detection and by ≈ 1.75 times (colorimetric mode) and ≈13.09 times (photothermal mode) for T-2 detection. As a proof-of-concept application, this work provides a reference to the design of DSM-LFIA for food safety detection.

Fortified Dual-Spectral Overlap with Enhanced Colorimetric/Fluorescence Dual-Response Immunochromatography for On-Site Bimodal-Type Gentamicin Monitoring.

Immunochromatography (ICA) remains untapped toward enhanced sensitivity and applicability for fulfilling the nuts and bolts of on-site food safety surveillance. Herein, we report a fortified dual-spectral overlap with enhanced colorimetric/fluorescence dual-response ICA for on-site bimodal-type gentamicin (Gen) monitoring by employing polydopamine (PDA)-coated AuNPs (APDA) simultaneously serving as a colorimetric reporter and a fluorescence quencher. Availing of the enhanced colorimetric response that originated from the PDA layer, the resultant APDA exhibits less required antibody and immunoprobes in a single immunoassay, which facilitates improved antibody utilization efficiency and immuno-recognition in APDA-ICA. Further integrated with the advantageous features of fortified excitation and emission dual-spectral overlap for the Arg/ATT-AuNCs, this APDA-ICA with a "turn on/off" pattern achieves the visual limits of detection of 1.0 and 0.5 ng mL-1 for colorimetric and fluorescence patterns (25- and 50-fold lower than standard AuNPs-ICA). Moreover, the excellent self-calibration and satisfactory recovery of 79.03-118.04% were shown in the on-site visual colorimetric-fluorescence analysis for Gen in real environmental media (including real river water, an urban aquaculture water body, an aquatic product, and an animal byproduct). This work provides the feasibility of exploiting fortified dual-spectral overlap with an enhanced colorimetric/fluorescence dual response for safeguarding food safety and public health.

A cheaper substitute for HRP: ultra-small Cu-Au bimetallic enzyme mimics with infinitesimal steric hindrance to promote catalytic lateral flow immunodetection of clenbuterol.

A highly sensitive lateral flow immunoassay (LFIA) is developed for the enzyme-catalyzed and double-reading determination of clenbuterol (CLE), in which a new type of probe was adopted through the direct electrostatic adsorption of ultra-small copper-gold bimetallic enzyme mimics (USCGs) and monoclonal antibodies. In the assay, based on the peroxidase activity of USCG, the chromogenic substrate TMB-H2O2 was introduced to trigger its color development, and the results were compared with those before catalysis. The detection sensitivity after catalysis is 0.03 ng mL-1 under optimal circumstances, which is 6-fold better than that of the traditional Au NPs-based LFIA and 2-fold greater than that before catalysis. This approach was successfully applied to the detection of CLE in milk, pork and mutton samples with an optimum assay time of 7 min and best catalytic time of 80 s, after which satisfactory recoveries of 98.53-117.79% were obtained. Cu-Au nanoparticles as a signal tag and the use of their nanozyme properties are the first applications in the field of LFIA. This work can be a promising exhibition for the application of a cheaper substitute for HRP, ultra-small bimetallic enzyme mimics, in LFIAs.

Precise Spectral Overlap-Based Donor-Acceptor Pair for a Sensitive Traffic Light-Typed Bimodal Multiplexed Lateral Flow Immunoassay.

Bimodal-type multiplexed immunoassays with complementary mode-based correlation analysis are gaining increasing attention for enhancing the practicability of the lateral flow immunoassay (LFIA). Nonetheless, the restriction in visually indistinguishable multitargets induced by a single fluorescent color and difficulty in single acceptor ineffectual fluorescence quenching due to the various spectra of multiple different donors impede the further execution of colorimetric-fluorescence bimodal-type multiplexed LFIAs. Herein, the precise spectral overlap-based donor-acceptor pair construction strategy is proposed by regulating the size of the nanocore, coating it with an appropriate nanoshell, and selecting a suitable fluorescence donor with distinct colors. By in situ coating Prussian blue nanoparticles (PBNPs) on AuNPs with a tunable size and absorption spectrum, the resultant APNPs demonstrate efficient fluorescence quenching ability, higher colloidal stability, remarkable colorimetric intensity, and an enhanced antibody coupling efficiency, all of which facilitate highly sensitive bimodal-type LFIA analysis. Following integration with competitive-type immunoreaction, this precise spectral overlap-supported spatial separation traffic light-typed colorimetric-fluorescence dual-response assay (coined as the STCFD assay) with the limits of detection of 0.013 and 0.152 ng mL-1 for ractopamine and clenbuterol, respectively, was proposed. This work illustrates the superiority of the rational design of a precise spectral overlap-based donor-acceptor pair, hinting at the enormous potential of the STCFD assay in the point-of-care field.