Regio- and stereoselective access to highly substituted vinylphosphine oxides via metal-free electrophilic phosphonoiodination of alkynes.

In general, the P-centered ring-opening of quaternary phosphirenium salts (QPrS) predominantly leads to hydrophosphorylated products, while the C-centered ring-opening is primarily confined to intramolecular nucleophilic reactions, resulting in the formation of phosphorus-containing cyclization products instead of difunctionalized products generated through intermolecular nucleophilic processes. Here, through the promotion of ring-opening of three-member rings by iodine anions and the quenching of electronegative carbon atoms by iodine cations, we successfully synthesize ß-functionalized vinylphosphine oxides by the P-addition of QPrS intermediates generated in situ. Multiple ß-iodo-substituted vinylphosphine oxides can be obtained with exceptional regio- and stereo-selectivity by reacting secondary phosphine oxides with unactivated alkynes. In addition, a variety of ß-functionalized vinylphosphine oxides converted from C-I bonds, especially the rapid construction of benzo[b]phospholes oxides, demonstrates the significance of this strategy.

Use of a pH-responsive imatinib mesylate sustained-release hydrogel for the treatment of tendon adhesion by inhibiting PDGFRß/CLDN1 pathway.

Adhesion after tendon injury, which can result in limb movement disorders, is a common clinical complication; however, effective treatment methods are lacking. Hyaluronic acid hydrogels are a new biomedical material used to prevent tendon adhesion owing to their good biocompatibility. In addition, potential drugs that inhibit adhesion formation have gradually been discovered. The anti-adhesion effects of a combination of loaded drugs into hydrogels have become an emerging trend. However, current drug delivery systems usually lack specific regulation of drug release, and the effectiveness of drugs for treating tendon adhesions is mostly flawed. In this study, we identified a new drug, imatinib mesylate (IM), that prevents tendon adhesion and explored its related molecular pathways. In addition, we designed a pH-responsive sustained-release hydrogel for delivery. Using the metal-organic framework ZIF-8 as a drug carrier, we achieved controlled drug release to increase the effective drug dose at the peak of adhesion formation to achieve better therapeutic effects. The results showed that IM blocked the formation of peritendon adhesions by inhibiting the PDGFRß/ERK/STAT3/CLDN1 pathway. Furthermore, the hydrogel with ZIF-8 exhibited better physical properties and drug release curves than the hydrogel loaded only with drugs, showing better prevention and treatment effects on tendon adhesion.

Iron ions-sequestrable and antioxidative carbon dot-based nano-formulation with nitric oxide release for Parkinson's disease treatment.

Nondestructive penetration of the blood-brain barrier (BBB) to specifically prevent iron deposition and the generation of reactive oxygen species (ROS) shows great potential for treating Parkinson's disease (PD). However, effective agents with distinct mechanisms of action remain scarce. Herein, a N-doping carbon dot (CD) emitting red light was prepared, which can sacrifice ROS and produce nitric oxide (NO) owing to its surface N-involved groups conjugated to the sp2-hybrided π-system. Meanwhile, CD can chelate iron ions, thus depressing the catalytic Fe cycle and *OH detaching to inhibit the Fenton reaction. By modifying lactoferrin (Lf) via polyethylene glycol (PEG), the resulting CD-PEG-Lf (CPL) can nondestructively cross the BBB, targeting the dopaminergic neurons via both NO-mediated reversible BBB opening and Lf receptor-mediated transportation. Accordingly, it can serve as an antioxidant, reducing oxidative stress via its unique iron chelation, free radical sacrificing, and synergy with iron reflux prevention originating from Lf. Thus, it can significantly reduce brain inflammation and improve the behavioral performance of PD mice. Additionally, CPL can image the PD via its red fluorescence. Finally, this platform can be metabolized out of the brain through cerebrospinal fluid circulation without causing obvious side effects, promising a robust treatment for PD.

Unfolding Protein-Based Hapten Coupling via Thiol-Maleimide Click Chemistry: Enhanced Immunogenicity in Anti-Nicotine Vaccines Based on a Novel Conjugation Method and MPL/QS-21 Adjuvants.

Vaccines typically work by eliciting an immune response against larger antigens like polysaccharides or proteins. Small molecules like nicotine, on their own, usually cannot elicit a strong immune response. To overcome this, anti-nicotine vaccines often conjugate nicotine molecules to a carrier protein by carbodiimide crosslinking chemistry to make them polymeric and more immunogenic. The reaction is sensitive to conditions such as pH, temperature, and the concentration of reactants. Scaling up the reaction from laboratory to industrial scales while maintaining consistency and yield can be challenging. Despite various approaches, no licensed anti-nicotine vaccine has been approved so far due to the susboptimal antibody titers. Here, we report a novel approach to conjugate maleimide-modified nicotine hapten with a disulfide bond-reduced carrier protein in an organic solvent. It has two advantages compared with other approaches: (1) The protein was unfolded to make the peptide conformation more flexible and expose more conjugation sites; (2) thiol-maleimide "click" chemistry was utilized to conjugate the disulfide bond-reduced protein and maleimide-modified nicotine due to its availability, fast kinetics, and bio-orthogonality. Various nicotine conjugate vaccines were prepared via this strategy, and their immunology effects were investigated by using MPL and QS-21 as adjuvants. The in vivo study in mice showed that the nicotine-BSA conjugate vaccines induced high anti-nicotine IgG antibody titers, compared with vaccines prepared by using traditional condensation methods, indicating the success of the current strategy for further anti-nicotine or other small-molecule vaccine studies. The enhancement was more significant by using MPL and QS-21 than that of traditional aluminum adjuvants.

Electron-Assisted Generation and Straight Movement of Skyrmion Bubble in Kagome TbMn6Sn6.

Topological magnetic textures are promising candidates as binary data units for the next-generation memory device. The precise generation and convenient control of nontrivial spin topology at zero field near room temperature endows the critical advantages in skyrmionic devices but is not simultaneously integrated into one material. Here, in the Kagome plane of quantum TbMn6Sn6, the expedient generation of the skyrmion bubbles in versatile forms of lattice, chain, and isolated one by converging the electron beam, where the electron intensity gradient contributes to the dynamic generation from local anisotropy variation near spin reorientation transition (SRT) is reported. Encouragingly, by utilizing the dynamic shift of the SRT domain interface, the straight movement is actualized with the skyrmion bubble slave to the SRT domain interface forming an elastic composite object, avoiding the usual deflection from the skyrmion Hall effect. The critical contribution of the SRT domain interface via conveniently electron-assisted heating is further theoretically validated in micromagnetic simulation, highlighting the compatible application possibility in advanced devices.

In Situ Attached Photothermal Immunomodulation-Enhanced Nanozyme for the Inhibition of Postoperative Malignant Glioma Recurrence.

Glioblastoma (GBM) is one of the most challenging malignant brain tumors to treat. Herein, we describe a nanoenzyme hemostatic matrix strategy with the tumor cavity in situ application that simultaneously serves as photothermal agent and induces immunogenic cell death after GBM surgical resection to enhance the antitumor immunity and delay tumor recurrence. The hemostatic matrix system (Surgiflo@PCN) contains Surgiflo, a multispace structure that can be used to penetrate different shapes of tumor cavities to prevent postoperative tumor cavity hemorrhage. As well, porous palladium-copper nanoclusters (PCNs) have adjustable enzyme-like activities (oxidase, peroxidase, and catalase) responsible for formation of reactive oxygen species (ROS) under near-infrared (808 nm) laser irradiation. When the Surgiflo@PCN entered the resected tumor cavity, the first action was the direct killing of glioma cells via ROS and photothermal therapy (PTT). The second action was the induction of immunogenic cell death by PCN-enhanced oxidative stress and PTT, which reversed the immunosuppressive tumor microenvironment and enhanced the antitumor immune response. This eradicated residual glioma cells and prevented recurrence. The collective findings demonstrate that Surgiflo@PCN kills glioma cells directly through ROS and PTT and enhances antiglioma immunity and kills glioma cells indirectly. The "one-stone, two-birds" strategy could become an effective photothermal immunotherapy in GBM patients.

Diabetes immunity-modulated multifunctional hydrogel with cascade enzyme catalytic activity for bacterial wound treatment.

Diabetes immunity-modulated wound treatment in response to the varied microenvironments at different stages remains an urgent challenge. Herein, glucose oxidase (GOx) and quasi-amorphous Fe2O3 are co-incorporated into Zn-MOF nanoparticle (F-GZ) for cascade enzyme catalytic activities, where not only the high blood glucose in the wound is consumed via the GOx catalysis, but also the effective anti-bacteria is achieved via the degradedly released Zn2+ synergistically with the catalytically produced ·OH during the bacterial infection period with the low pH microenvironment. Simultaneously, the reactive oxygen species scavenging and hypoxia relief is realized via catalyzing H2O2 to produce O2 at the relatively elevated pH environment during the wound recovery period. Subsequently, a multifunctional hydrogel with injectable, self-healing and hemostasis abilities, as well as uniformed F-GZ loading is prepared via the copolymerization reaction. This hydrogel behaves as F-GZ but reduces the toxic effects, which thus accelerates the diabetic wound healing. More importantly, this hydrogel is found to modulate the diabetes immunity possibly mediated via the released Zn2+, which thus contributes to the recovered pancreatic islet functions with improved glucose tolerance and increased insulin secretion for enhanced diabetic wound treatments. This work initiates a new strategy for simultaneous diabetic wound management and also suggests a potential way for diabetic immunity modulation.

Hypervalent iodine-mediated ß-difluoroalkylboron synthesis via an unusual 1,2-hydrogen shift enabled by boron substitution.

ß-Difluoroalkylborons, featuring functionally important CF2 moiety and synthetically valuable boron group, have great synthetic potential while remaining synthetically challenging. Herein we report a hypervalent iodine-mediated oxidative gem-difluorination strategy to realize the construction of gem-difluorinated alkylborons via an unusual 1,2-hydrogen migration event, in which the (N-methyliminodiacetyl) boronate (BMIDA) motif is responsible for the high regio- and chemoselectivity. The protocol provides facile access to a broad range of ß-difluoroalkylborons under rather mild conditions. The value of these products was demonstrated by further transformations of the boryl group into other valuable functional groups, providing a wide range of difluorine-containing molecules.

A histological study of atherosclerotic characteristics in age-related macular degeneration.

This study investigated the pathogenesis of age-related macular degeneration (AMD) using histological methods that are commonly used for atherosclerotic vascular disease (ASVD). 1 normal, 3 early dry AMD, and 1 late dry AMD eyes were obtained from the Lions Eye Bank of Oregon and systematically dissected. They were stained with hematoxylin and eosin, Oil red O, Masson, Elastica van Gieson, Alizarin red, and Prussian blue. Additionally, the normal and late dry AMD eyes were immunostained for a-smooth muscle actin, CD45, and CD68 with Nile red and DAPI. Correlations were found between severity of AMD and lipid accumulation in the deep sclera (+), numbers of drusen between the Bruch's membrane and retinal pigment epithelium (RPE) (+), amount of collagen in the deep sclera (+), and amount of elastin in the deep sclera (-) (P < 0.1). Geographic atrophy, RPE detachment, and abnormal capillary shape and distribution in the choriocapillaris were observed in the fovea of late AMD. There were no stenosis, plaque, hemorrhage, and calcification. Additionally, late AMD tended to have higher smooth muscle thicknesses of the choroidal vascular walls, lower numbers of T lymphocytes in the choroid, and higher numbers of macrophages near the RPE and in the choroid relative to normal (P < 0.1). Macrophages-derived foam cells were detected near the Bruch's membrane in late AMD. Therefore, the present study showed many histological characteristics of ASVD in AMD, which suggests an association between them; however, there were also some histological characteristics of ASVD that were not found in AMD, which indicates that there exist pathogenic differences between them. The results generally support the vascular model of AMD, but some details still need clarification.

Au3+ Species Boost the Catalytic Performance of Au/ZnO for the Semi-hydrogenation of Acetylene.

Au nanoparticles have garnered remarkable attention in the chemoselective hydrogenation due to their extraordinary selectivity. However, the activity is far from satisfactory. Knowledge of the structure-performance relationship is a key prerequisite for rational designing of highly efficient Au-based hydrogenation catalysts. Herein, diverse Au sites were created through engineering their interactions with supports, specifically via adjusting the support morphology, that is, flower-like ZnO (ZnO-F) and disc-like ZnO (ZnO-D), and the catalyst pretreatment atmosphere, that is, 10 vol % O2/Ar and 10 vol % H2/Ar (denoted as -O and -H, respectively). The four samples of Au/ZnO were characterized by various techniques and evaluated in the semi-hydrogenation of acetylene. The transmission electron microscopy results indicated that the Au particle sizes are almost similar for our Au/ZnO catalysts. The charge states of Au species demonstrated by X-ray photoelectron spectroscopy, diffuse reflectance infrared Fourier transform spectroscopy with CO as the probe molecule, and simulation based on density functional theory, however, are greatly dependent on the ZnO shape and pretreatment atmosphere, that is, the percentage of Au3+ reduces following the order of Au/ZnO-F-O > Au/ZnO-F-H > Au/ZnO-D-O > Au/ZnO-D-H. The testing results showed that the Au/ZnO-F-O catalyst containing maximum of Au3+ possesses the optimal activity with 1.8 × 10-2 s-1 of specific activity at 200 °C, around 16.5-fold of that for Au/ZnO-D-H. More interestingly, the specific rate at 200 °C and the average conversion/selectivity in the entire operating temperature range are well correlated with the redox states of the Au species, indicating that Au3+ sites are more active for acetylene hydrogenation. A plausible explanation is that the Au3+ species not only facilitate acetylene adsorption via electrostatic interactions but also favor the heterolysis of H2 via constructing frustrated Lewis pairs with O.

Assembly of multicyclic isoquinoline scaffolds from pyridines: formal total synthesis of fredericamycin A.

The construction of an isoquinoline skeleton typically starts with benzene derivatives as substrates with the assistance of acids or transition metals. Disclosed here is a concise approach to prepare isoquinoline analogues by starting with pyridines to react with ß-ethoxy α,ß-unsaturated carbonyl compounds under basic conditions. Multiple substitution patterns and a relatively large number of functional groups (including those sensitive to acidic conditions) can be tolerated in our method. In particular, our protocol allows for efficient access to tricyclic isoquinolines found in hundreds of natural products with interesting bioactivities. The efficiency and operational simplicity of introducing structural complexity into the isoquinoline frameworks can likely enable the collective synthesis of a large set of natural products. Here we show that fredericamycin A could be obtained via a short route by using our isoquinoline synthesis as a key step.

Three-dimensional analysis of mandibular characteristics in patients with skeletal Class II malocclusion and chin deviation.

INTRODUCTION: This study aimed to analyze adults with mandibular characteristics of skeletal Class II malocclusion with chin deviation. METHODS: Seventy-five adult patients aged from 18 to 35 years were included and divided into 3 groups on the basis of sagittal skeletal pattern and chin deviation: skeletal Class I symmetry group, skeletal Class II symmetry group, and skeletal Class II asymmetry group (25 patients per group). Mandibular measurements on cone-beam computed tomography images were performed, and the differences between 2 sides in each group and the differences among the 3 groups were investigated. RESULTS: Compared with the contralateral side, the deviated side of patients in the Class II asymmetry group showed significantly smaller condyle angle to midsagittal plane, condylar height, ramal length, and length of the mandibular body, whereas it showed a significantly larger distance from condylion to the midsagittal plane, ramus angle to the horizontal plane, and distance from gonion to the midsagittal plane. Most linear measurements in the Class II symmetry group were significantly smaller than those in the Class I symmetry group. These linear measurements on the contralateral side of the Class II asymmetry group showed no significant difference with the Class I symmetry group, and these measurements on the deviated side of the Class II asymmetry group showed no significant difference with the Class II symmetry group. CONCLUSIONS: Length of the mandible, rotation of condyle, the inclination of the ramus, and position of gonion should be considered in subjects with skeletal Class II asymmetry when making diagnosis and treatment planning.

Inorganic Recognizer-Assisted Homogeneous Electrochemiluminescence Determination of Organophosphorus Pesticides via Target-Controlled Emitter Release.

Given the relevance of organophosphorus pesticides (OPs) with food safety, it is highly urgent to develop sensitive and reliable sensors for OPs. However, most of the OP sensors are developed based on colorimetric and fluorescent techniques, which are limited to severe interference of color and fluorescence from pigments and organic acids in agricultural crops. Herein, we develop an inorganic recognizer-based homogeneous electrochemiluminescence (ECL) sensor for the highly sensitive and credible determination of OPs based on manganese dioxide and tris(2,2'-bipyridine)ruthenium [Ru(bpy)3]2+. Through electrostatic interaction, manganese dioxide nanoflakes-[Ru(bpy)3]2+ nanocomposites (MnNFs-Ru) are formed and exhibit a weak ECL signal due to the confinement of [Ru(bpy)3]2+ in MnNFs-Ru. Interestingly, MnNFs-Ru are capable of recognizing thiols due to the analyte-initiated reduction of MnNFs into Mn2+ and release of [Ru(bpy)3]2+ from MnNFs-Ru into solution. Further, MnNFs-Ru are employed for the homogeneous ECL determination of OPs, where acetylcholinesterase (AChE) catalyzes the hydrolysis of acetylthiocholine (ATCh) into thiocholine, which in turn decomposes MnNFs of MnNFs-Ru into Mn2+, and OPs inhibit AChE activity. This study widens the application of inorganic recognizers from colorimetry/fluorescence to homogeneous ECL and effectively avoids the interference of color and fluorescence, opening up a new path to the development of high-performance OP sensors and supplying a promising tool for guaranteed OP-related food safety.

Improved performance of soy protein adhesive with melamine-urea-formaldehyde prepolymer.

In recent years, soy protein adhesive, as an environmentally friendly bio-based adhesive, has attracted extensive attention. In this study, in order to ameliorate the bonding quality of soy protein isolate (SPI) adhesive, the melamine-urea-formaldehyde prepolymer (MUFP) was synthesized, and different amounts of it were introduced into the SPI adhesive as a cross-linking agent. Fourier transform infrared (FT-IR) spectroscopy, gel permeation chromatography (GPC), thermogravimetric analyze (TGA), and scanning electron microscopy (SEM) were used to analysis the mechanism of modification. The results of plywood test indicated that the wet bonding strength of the adhesives was first increased and then decreased with an increase in the amount of MUFP additive. FT-IR, TGA, and SEM tests suggested that the introduction of MUFP could promote the establishment of a cross-linking structure in the cured adhesive layer to improve the bonding quality of adhesives, but presence of excessive MUFP could introduce hydrophilic groups and adversely affect water resistance.

The posterior eye with age-related macular degeneration has isotropic and nonlinear viscoelastic properties.

Here we characterize and compare the anisotropic and nonlinear viscoelastic properties of the posterior eye of advanced dry age-related macular degeneration (AMD) patients and age-matched normal subjects. Ten normal horizontal, ten normal vertical, ten AMD horizontal, and ten AMD vertical strips of the macular retina and the underlying choroid and sclera were preloaded, preconditioned, and subjected to incremental stress-relaxation tests in body-temperature saline. The stress-relaxation response was characterized by a fully nonlinear viscoelastic formulation in which the relaxation modulus was approximated by a Prony series and a second-order polynomial using the comprehensive viscoelastic characterization method. Normal retina, choroid, and sclera were found to be anisotropic, whereas AMD tissues were isotropic. AMD retina and choroid showed greater stress-relaxation response than normal tissues (p < 0.05), whereas AMD sclera had smaller stress-relaxation response than normal tissue (p < 0.05). The nonlinear viscoelastic stress-strain relationship of the posterior eye is hence describable for the first time.

Label-free homogeneous electrochemical detection of MicroRNA based on target-induced anti-shielding against the catalytic activity of two-dimension nanozyme.

In traditional homogeneous electrochemical sensing system, methylene blue was stricken with nonspecific intercalation and weak stability, inevitably distorting the diagnosis results. Given the unique catalytic activity of oxidase- and peroxidase-like nanozymes, it is interesting to develop a nanozyme-based homogeneous electrochemical biosensor. Whereas, the preparation of nanozymes with dual enzyme-like activities and two dimensional (2D) morphology is a great challenge. Herein, a soft template-directed wet chemical approach was proposed for preparation of 2D MnO2 nanoflakes, in which the morphology can be easily tuned by the template dosage. Interestingly, not only the oxidase-like activity was discovered, but 2D MnO2 nanoflakes also display a significant peroxidase-like activity. Noticeably, 2D MnO2 nanoflakes exhibit superior response to single stranded deoxyribonucleic acid (ssDNA) over double stranded DNA in the aspect of binding and catalytic activity, which triggers a highly sensitive homogeneous electrochemical detection of microRNA. This study about finding nanozymes with dual enzyme-like activities and ssDNA with inhibiting effect will set up a new avenue to extend the application range of nanozymes and throws a new light on the development of higher-performance electrochemical biosensors.

Quaternary Ammonium Salt-Functionalized Tetraphenylethene Derivative Boosts Electrochemiluminescence for Highly Sensitive Aqueous-Phase Biosensing.

Aggregation induced emission active compounds (AIEgens) have appeared as a new kind of electrochemiluminescence (ECL) emitters due to their bright emission in the aggregated state but lack functional groups. Herein, we report a quaternary ammonium salt groups-functionalized AIEgen (QAU-1) and discover that coating QAU-1 on the indium tin oxide (ITO) surface (QAU/ITO) enabled QAU-1 to display significant cathodic ECL emission compared with that of QAU-1 in the dissolved state. Inspired by this, we applied QAU-1 as emitters to develop a novel ECL biosensor (Fc-DNA/QAU/ITO) through electrostatic attraction between QAU/ITO and a ferrocene-labeled ssDNA (Fc-DNA), and the developed biosensor was employed to detect bleomycin (BLM) with high sensitivity based on the target-initiated specific cleavage and subsequent removal of Fc molecules from the electrode. We envision this work will open up a new avenue to development of high-performance ECL biosensors, which will display a significant potential application in the field of analysis.

Equipment-free and visual detection of multiple biomarkers via an aggregation induced emission luminogen-based paper biosensor.

Early and accurate disease diagnosis is of great appeal for saving patients' life, but requires biomarkers to be sensitively detected with simplicity, convenience, and low cost. Exploring the development of a high-performance fluorescence biosensor for biomarkers solid, equipment-free and visual biosensing is highly urgent but faces enormous challenges. Herein, we proposed a brand-new fluorescence system by integrating a typical aggregation induced emission dye (TPE-BTD) with dopamine for multiple biomarkers sensitive detection based on target-induced catalyzing oxidation. The system comprising TPE-BTD and dopamine emits strong fluorescence; with horseradish peroxidase (HRP) or HRP-mimicking DNAzyme and H2O2 being added, significant oxidation on dopamine occurs to generate dopachrome, which actuated the inner filter effect (IFE) due to the overlap of its absorbtion curve and emission spectrum of TPE-BTD, subsequently decreasing fluorescence emission and displaying a rapid and sensitive response to H2O2 and G-quadruplex DNA. We further apply TPE-BTD/dopamine system in analysis of glucose and DNA adenine methylation methyltransferase (Dam MTase) based on target-initiated signal transduction. Finally, TPE-BTD was employed as emitters in fabrication of paper biosensors, which can achieve solid, equipment-free and visual detection of multiple biomarkers based on the high emission performance of TPE-BTD, opening up a new pathway to development of biosensors for practical application. We expect this sensing conception will be helpful in development of practical biosensors, and this sensor will find more applications in disease diagnosis.

One-Step Synthesis of Methylene Blue-Encapsulated Zeolitic Imidazolate Framework for Dual-Signal Fluorescent and Homogeneous Electrochemical Biosensing.

In vitro diagnosis requires target biomarkers to be reliably detected at an ultralow level. A dual-signal strategy permits self-calibration to overcome the interferences of experimental and environmental factors, and thus is regarded as a promising approach. However, currently reported works mainly concentrated on the same forms of energy of output signals. Herein, we propose a one-step strategy for synthesis of methylene blue-encapsulated zeolitic imidazolate framework-90 (MB@ZIF-90) with high loading, unique dual-signal property, exceptional recognition capability, and good stability, and we further pioneer MB@ZIF-90 as a dual-signal biosensor for label-free, enzyme-free, and ultrasensitive detection of adenosine triphosphate (ATP) by integration of fluorescence and homogeneous electrochemical techniques. The recognition of MB@ZIF-90 by target ATP spurs the decomposition of ZIF-90, subsequently permitting MB to be released into a supernatant. As compared to the case where ATP does not exist, obviously increased intensities in fluorescence and differential pulse voltammetry current are observed and both signals are directly proportional to ATP concentrations. Thus, the MB@ZIF-90-based biosensor achieved dual-signal detection of ATP in an ultrasensitive manner and displayed a more reliable diagnosis result than previously reported ATP biosensors. This dual-signal strategy provides a new opportunity to develop high-performance biosensors for in vitro diagnosis and demonstrates great potential for future applications in bioinformatics and clinical medicine.

In situ generated nanozyme-initiated cascade reaction for amplified surface plasmon resonance sensing.

A novel nanozyme-based surface plasmon resonance (SPR) sensor was successfully developed based on the target-induced in situ generation of AuNPs and a AuNP-guided cascade reaction, with Hg2+ as the target analyte.