Split-Type Photoelectrochemical/Visual Sensing Platform Based on SnO2/MgIn2S4/Zn0.1Cd0.9S Composites and Au@Fe3O4 Nanoparticles for Ultrasensitive Detection of Neuron Specific Enolase.

Herein, a novel dual mode detection system of split-type photoelectrochemical (PEC) and visual immunoassay was developed to detect neuron specific enolase (NSE), which achieved simultaneous and reliable NSE detection due to the completely different signal readouts and transduction mechanism. Specifically, specific reactions of antigens and antibodies were performed in 96-microwell plates. Gold nanoparticle (Au NP)-loaded Fe3O4 (Au@Fe3O4) NPs were used as secondary antibody markers and signal regulators, which could produce a blue-colored solution in the presence of 3,3',5,5'-tetramethylbenzidine (TMB) and H2O2 because of its peroxidase-like activity. Therefore, the visual detection of NSE was realized, making the results more intuitive. Meanwhile, the above biological process could also be used as part of the split-type PEC sensing platform. Oxidized TMB and Fe3+ were consumptive agents of the electron donor, which both realized the double quenching of PEC signal generated by the SnO2/MgIn2S4/Zn0.1Cd0.9S composites. Owing to the waterfall band structure, SnO2/MgIn2S4/Zn0.1Cd0.9S composites partially absorb visible light and effectively inhibit the electron-hole recombination, thereby providing significantly enhanced and stable initial signal. On the basis of the multiple signal amplification strategy and the split-type mode, NSE could be sensitively detected with a low detection limit of 14.0 fg·mL-1 (S/N = 3) and a wide linear range from 50.0 fg·mL-1 to 50.0 ng·mL-1.

Enhancing Electrochemiluminescence Efficiency through Introducing Atomically Dispersed Ruthenium in Nickel-Based Metal-Organic Frameworks.

The successful application of electrochemiluminescence (ECL) in various fields required continuous exploration of novel ECL signal emitters. In this work, we have proposed a pristine ECL luminophor named NiRu MOFs, which owned extremely high and stable ECL transmission efficiency and was synthesized via a straightforward two-step hydrothermal pathway. The foundation framework of pure Ni-MOFs with the initial structure was layered-pillared constructed by the coordinated octahedrally divalent between nickel and terephthalic acid (BDC). The terephthalates were coordinated and pillared directly to the nickel hydroxide layers and the three-dimensional framework was formed, which had a weak ECL response strength. Then, the ruthenium pyridine complex was recombined with pure Ni-MOFs to produce NiRu MOFs and part of the introduced ruthenium was atomically dispersed in the layered-pillared structure through an ion-exchange method, which led to the ECL luminous efficiency being significantly boosted more than pure Ni-MOFs. In order to verify the superiority of this newly synthesized illuminant, an ECL immunoassay model has been designed, and the results demonstrated that it had extremely strong and steady signal output in practical application. This study realized an efficient platform in ECL immunoassay application with the limit of detection of 0.32 pg mL-1 for neuron-specific enolase (NSE). Therefore, the approach which combined the pristine pure Ni-MOFs and the star-illuminant ruthenium pyridine complex would provide a convenient and meaningful solution for exploring the next-generation ECL emitters.

Self-Luminescent Lanthanide Metal-Organic Frameworks as Signal Probes in Electrochemiluminescence Immunoassay.

The successful use of electrochemiluminescence (ECL) in immunoassay for clinical diagnosis requires development of novel ECL signal probes. Herein, we report lanthanide (Ln) metal-organic frameworks (LMOFs) as ECL signal emitters in the ECL immunoassay. The LMOFs were prepared from precursors containing Eu (III) ions and 5-boronoisophthalic acid (5-bop), which could be utilized to adjust optical properties. Investigations of ECL emission mechanisms revealed that 5-bop was excited with ultraviolet photons to generate a triplet-state, which then triggered Eu (III) ions for red emission. The electron-deficient boric acid decreased the energy-transfer efficiency from the triplet-state of 5-bop to Eu (III) ions; consequently, both were excited with high-efficiency at single excitation. In addition, by progressively tailoring the atomic ratios of Ni/Fe, NiFe composites (Ni/Fe 1:1) were synthesized with more available active sites, enhanced stability, and excellent conductivity. As a result, the self-luminescent europium LMOFs displayed excellent performance characteristics in an ECL immunoassay with a minimum detectable limit of 0.126 pg mL-1, using Cytokeratins21-1 (cyfra21-1) as the target detection model. The probability of false positive/false negative was reduced dramatically by using LMOFs as signal probes. This proposed strategy provides more possibilities for the application of lanthanide metals in analytical chemistry, especially in the detection of other disease markers.

Homogeneous production and characterization of recombinant N-GlcNAc-protein in Pichia pastoris.

BACKGROUND: Therapeutic glycoproteins have occupied an extremely important position in the market of biopharmaceuticals. N-Glycosylation of protein drugs facilitates them to maintain optimal conformations and affect their structural stabilities, serum half-lives and biological efficiencies. Thus homogeneous N-glycoproteins with defined N-glycans are essential in their application in clinic therapeutics. However, there still remain several obstacles to acquire homogeneous N-glycans, such as the high production costs induced by the universal utilization of mammalian cell expression systems, the non-humanized N-glycan structures and the N-glycosylation microheterogeneities between batches. RESULTS: In this study, we constructed a Pichia pastoris (Komagataella phaffii) expression system producing truncated N-GlcNAc-modified recombinant proteins through introducing an ENGase isoform (Endo-T) which possesses powerful hydrolytic activities towards high-mannose type N-glycans. The results showed that the location of Endo-T in different subcellular fractions, such as Endoplasmic reticulum (ER), Golgi or cell membrane, affected their hydrolytic efficiencies. When the Endo-T was expressed in Golgi, the secreted IgG1-Fc region was efficiently produced with almost completely truncated N-glycans and the N-GlcNAc modification on the glycosite Asn297 was confirmed via Mass Spectrometry. CONCLUSION: This strategy develops a simple glycoengineered yeast expression system to produce N-GlcNAc modified proteins, which could be further extended to different N-glycan structures. This system would provide a prospective platform for mass production of increasing novel glycoprotein drugs.

Label-free electrochemical immunosensor based on biocompatible nanoporous Fe3O4 and biotin-streptavidin system for sensitive detection of zearalenone.

In this study, a sensitive label-free electrochemical immunosensor was designed based on nanoporous Fe3O4 and a biotin-streptavidin system to specifically detect zearalenone (ZEN). Herein, nanoporous Fe3O4 was employed to carry streptavidin to prepare the highly sensitive immunosensor. The application of nanoporous Fe3O4 and the biotin-streptavidin reaction provided large amounts of antibodies on each conjugate, thus amplifying the detected signal. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were conducted to characterize the modification with ZEN. Factors which might influence the properties of the immunosensor, including concentration of nanoporous Fe3O4, pH of the buffer, incubation time and temperature were studied. Under the best conditions, the immunosensor displayed a highly sensitive response toward ZEN, ranging in concentration from 10.0 pg mL-1 to 3.00 ng mL-1 and 3.00 ng mL-1 to 12.0 ng mL-1, with a low detection limit of 3.7 pg mL-1. The results for analysis of human urine samples were satisfactory. Furthermore, this proposed method may find promising applications in the detection of other mycotoxins.

A photoelectrochemical immunosensor based on CdS/CdTe-cosensitized SnO2 as a platform for the ultrasensitive detection of amyloid ß-protein.

An ultrasensitive label-free photoelectrochemical (PEC) immunosensor was developed to detect amyloid ß-protein (Aß) based on CdS/CdTe-cosensitized SnO2 nanoflowers. Specifically, SnO2 with a flower-like porous nanostructure was utilized as a perfect substrate for the construction of PEC immunosensors, and the SnO2-modified electrode was first coated with CdTe quantum dots (QDs) and then further deposited with CdS by successive ionic layer adsorption and reaction techniques. The formed SnO2/CdS/CdTe-cosensitized structure exhibited excellent photocurrent intensity and was employed as an excellent photoactive matrix to immobilize Aß antibody to further construct the immunosensor. Under optimal conditions, the as-constructed PEC immunosensor was used to detect Aß and exhibited a wide linear concentration range from 0.5 pg mL-1 to 10 ng mL-1, with a low limit of detection (LOD, 0.18 pg mL-1, S/N = 3). Meanwhile, it also presented good reproducibility, specificity, and stability and may open a new promising platform for the clinical detection of Aß or other biomarkers.

Electrochemical assay of ampicillin using Fe3N-Co2N nanoarray coated with molecularly imprinted polymer.

Self-supported Fe3N-Co2N nanoarray with high electric conductivity and large surface area was prepared for growth of MIPs and further constructing a sensitive and stable electrochemical sensor. For the evaluation of its performance, Fe3N-Co2N is used as sensing electrode material, and AMP is used as template molecule to construct the MIP electrochemical sensor. Under the optimized conditions, the developed MIPs electrochemical sensor detects AMP with a low detection limit of 3.65 × 10-10 mol L-1 and shows outstanding reproducibility and stability. When the MIPs electrochemical sensor was applied to detect AMP in milk samples via standard addition method, the recovery within 97.06-102.43% with RSD of 1.05-2.11% was obtained. The fabrication of MIPs electrochemical sensor is highly promising for sensitive and selective electrochemical measurement and food safety testing. This work can provide theoretical guidance for truly challenging problems. Graphical abstract Principle diagram of MIP-EC sensor for detecting AMP Molecular imprinted polymers (MIPs) are widely performed for construction of electrochemical (EC) sensors especially for detecting small molecules in complex environment. However, the large-scale and robust preparation of MIPs in situ on sensor platform limits their practical applications. We fabricated a MIPs EC sensor based on Fe3N-Co2N in situ grown on carbon cloth (CC) as the substrate platform (Fe3N-Co2N/CC) combining with MIPs as the target recognition element for the label-free detection of AMP. Under the optimal conditions, the developed MIPs EC sensor can detect AMP with a low detection limit of 3.65 × 10-10 mol L-1. When the AMP in milk is detected by the proposed EC sensor, it shows ideal results. Therefore, the use of self-supported Fe3N-Co2N nanoarray as the platform for the fabrication of MIPs EC sensors is highly promising for sensitive and selective EC measurement and point-of-care testing.

Dual-Quenching Electrochemiluminescence Strategy Based on Three-Dimensional Metal-Organic Frameworks for Ultrasensitive Detection of Amyloid-ß.

We have proposed a dual-quenching electrochemiluminescence (ECL) strategy which is based on tris(2,2'-bipyridyl)ruthenium(II) [Ru(bpy)32+] as chromophores caged in three-dimensional (3D) zinc oxalate metal-organic frameworks [Ru(bpy)32+/zinc oxalate MOFs] for ultrasensitive detection of amyloid-ß (Aß). The three-dimensional chromophore connectivity in zinc oxalate MOFs provided a network for rapid excited-state energy transfer migration among Ru(bpy)32+ units which shielded the chromophores from solvent molecules and led to a high-energy Ru emission efficiency. In addition, we found that both Au nanoparticles and NiFe-based nanocube MOFs could contribute to the reduction of the ECL intensity of the chromophore. The ECL emission spectra of 3D Ru(bpy)32+/zinc oxalate MOFs overlapped appropriately with the ultraviolet-visible (UV-vis) absorption spectra of Au@NiFe MOFs composites, which could trigger the resonance energy transfer (RET) behavior between Ru(bpy)32+/zinc oxalate MOFs (donor) and Au@NiFe MOFs (acceptor), achieving the dual-quenching effect of Ru(bpy)32+ encapsulated in 3D zinc oxalate MOFs and significantly boosting the sensitivity of the Aß detection immunosensor. In order to examine the clinical practicability, we have applied it to verify the content of Aß solution ranging from 100 fg mL-1 to 50 ng mL-1 and obtained the calibration curve with high correlation coefficient, along with the low limit of detection of 13.8 fg mL-1. Above all, this work demonstrated an approach of constructing dual-quenching effect ECL immunosensors in whole 3D MOF systems and its application in ECL detection methodology.

Electrochemiluminescent immunosensor for prostate specific antigen based upon luminol functionalized platinum nanoparticles loaded on graphene.

A novel label-free electrochemiluminescent (ECL) immunosensor based upon luminol functionalized platinum nanoparticles loaded on graphene sheets (Lu-Pt@GS) as sensing platform was fabricated for highly sensitive and selective determination of prostate specific antigen (PSA). In this work, for the first time luminol was employed as both ECL luminescence reagent and reductants to in-situ reduce H2PtCl6 forming Pt NPs on surface of GS. A great deal of luminol could be attached onto the surface of Pt NPs within the reduction process, which can generate strong ECL emission. Pt NPs not only could enhance ECL signals of luminol but supply active sites for the immobilization of PSA antibodies with micro friendly environment. For preventing the consecutive reaction among luminol and H2O2, single-step cycle pulse was adopted, resulting in stable and strong ECL signals. Under optimized experimental conditions, the proposed ECL immunosensor acquired a wide linear range of 1 pg/mL to 10 ng/mL with a relatively low detection limit of 0.3 pg/mL for PSA. Furthermore, due to high sensitivity, simplicity and cost-effectiveness, the designed immunosensor provides a new method for detecting other important biomarkers in clinical analysis.

Preparation of AgCl Particles with Different Superwettabilities by Particle Size Regulation.

In this work, a simple ammonia evaporation process to obtain AgCl powder with arbitrary superwettability, without introducing any low-surface-free-energy modifier, was investigated. By controlling the recrystallization parameters of the ammonia evaporation process, AgCl crystals precipitated from AgCl-ammonia solution show different wettabilities ranging from superhydrophilicity, via hydrophilicity and hydrophobicity, to superhydrophobicity, with the same chemical composition and structure. Characterization of the obtained AgCl samples with different wettabilities confirms the decisive effect of particle size although light irradiation also causes their wettability transformation.

High level expression and glycosylation of recombinant Mycobacterium tuberculosis Ala-Pro-rich antigen in Pichia pastoris.

The Ala-Pro-rich Antigen (Apa) from Mycobacterium tuberculosis is a mannosylated protein with immunogenic and antigenic properties. The O-mannosylation is essential for its biological function in the process of colonization and invasion of host cells by M. tuberculosis. In this work, the gene encoding Apa was cloned from M. tuberculosis and expressed in Pichia pastoris GS115. In shake-flasks, the recombinant Apa was secreted into the culture media and purified with a yield of 0.6 g/L. Both N- and O-glycans were found in recombinant Apa. In P. pastoris the known M. tuberculosis-derived O-glycosites of Apa were modified with short chains of mannose units, and a few additional glycosylation sites were also observed. Therefore, the recombinant Apa expressed in P. pastoris has similar but not identical O-mannose patterns to the native protein from M. tuberculosis. P. pastoris and mycobacteria share similarities in the protein O-glycosylation pathway. Thus P. pastoris could be a potential powerful expression system to produce mycobacteria-derived glycoproteins.

An ultrasensitive electrochemical immunosensor for the detection of CD146 based on TiO2 colloidal sphere laden Au/Pd nanoparticles.

An ultrasensitive electrochemical immunosensor for the detection of cluster of differentiation 146 antigen (CD146) based on TiO2 colloidal sphere laden Au/Pd nanoparticles (Au/Pd@TiO2) was developed. In this work, reduced graphene oxide-tetraethylene pentamine (rGO-TEPA) was applied as an electrode modifying material to modify the surface of a glassy carbon electrode (GCE). Au/Pd@TiO2 was used as the secondary-antibody (Ab2) label for the fabrication of the immunosensor. Amperometric response of the immunosensor for electrocatalytic reduction of hydrogen peroxide (H2O2) was recorded. Electrochemical impedance spectroscopy (EIS) proved that fabrication of the immunosensor was successful. The anti-CD146 primary antibody (Ab1) was immobilized on the rGO-TEPA modified GCE by a cross-linking reagent of glutaraldehyde (GA). With Ab1 immobilized onto the rGO-TEPA modified GCE and Ab2 linked with Au/Pd@TiO2, the immunosensor displayed a wide linear range (0.0050-20 ng mL(-1)), a low detection limit (1.6 pg mL(-1)), good reproducibility, good selectivity and acceptable stability. The designed sensing strategy may provide a potential application in the detection of other tumor markers.

A sandwich-type immunosensor using Pd-Pt nanocrystals as labels for sensitive detection of human tissue polypeptide antigen.

A sandwich-type immunosensor was developed for the detection of human tissue polypeptide antigen (hTPA). In this work, a graphene sheet (GS) was synthesized to modify the surface of a glassy carbon electrode (GCE), and Pd-Pt bimetallic nanocrystals were used as secondary-antibody (Ab2) labels for the fabrication of the immunosensor. The amperometric response of the immunosensor for catalyzing hydrogen peroxide (H2O2) was recorded. And electrochemical impedance spectroscopy was used to characterize the fabrication process of the immunosensor. The anti-human tissue polypeptide antigen primary antibody (Ab1) was immobilized onto the GS modified GCE via cross-linking with 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride and N-hydroxysuccinimide (EDC/NHS). With Ab1 immobilized onto the GS modified GCE and Ab2 linked on Pd-Pt bimetallic nanocrystals, the immunosensor demonstrated a wide linear range (0.0050-15 ng ml(-1)), a low detection limit (1.2 pg ml(-1)), good reproducibility, good selectivity and acceptable stability. This design strategy may provide many potential applications in the detection of other cancer biomarkers.

Mental health and lower urinary tract symptoms: Results from the NHANES and Mendelian randomization study.

BACKGROUND: The clinical observations suggest a correlation between lower urinary tract symptoms (LUTSs) and mental health problems. Nonetheless, establishing a direct causal relationship between them remains challenging. METHODS: We initially conducted a cross-sectional study using 2005-2018 the National Health and Nutrition Examination Survey (NHANES) data. Multivariable-adjusted logistic regression was the primary statistical approach. Additionally, we employed Mendelian randomization (MR) to reducing confounding and reverse causation. Genetic instruments were obtained from publicly available genome-wide association study (GWAS) databases. Inverse Variance Weighted was the primary statistical method. RESULTS: The cross-sectional study involved 29,439 participants. Individuals with mental health problems had a higher risk of urinary incontinence (OR:4.38; 95%CI:3.32-5.76; P < 0.01) and overactive bladder (OR:2.31; 95%CI:2.02-2.63; P < 0.01). MR analysis then indicated a potential causal relationship between mental health problems and LUTSs. Depression symptoms was linked with urinary tract infection (UTI) (OR:1.005; 95%CI:1.003-1.008; PFDR < 0.01). Anxiety symptoms was related to the occurrence of UTI (OR:1.024; 95%CI:1.011-1.037; PFDR < 0.01) and bladder calcified/ contracted/ overactive (OR:1.017; 95%CI:1.007-1.027; PFDR < 0.01). The personality trait of neuroticism was related to the occurrence of cystitis (OR:1.072; 95%CI:1.022-1.125; PFDR = 0.02), extravasation of urine and difficulties with micturition (OR:1.001; 95%CI:1.001-1.002; PFDR < 0.01), and urinary frequency and incontinence (OR: 1.001; 95%CI:1.000-1.001; PFDR < 0.01). CONCLUSIONS: Our study provides various evidence for the correlation between mental health and LUTSs, emphasizing the significance of adopting a holistic approach to LUTSs management that incorporates both physical and psychological factors.

Advances in the Application of Transition-Metal Composite Nanozymes in the Field of Biomedicine.

Due to the limitation that natural peroxidase enzymes can only function in relatively mild environments, nanozymes have expanded the application of enzymology in the biological field by dint of their ability to maintain catalytic oxidative activity in relatively harsh environments. At the same time, the development of new and highly efficient composite nanozymes has been a challenge due to the limitations of monometallic particles in applications and the inherently poor enzyme-mimetic activity of composite nanozymes. The inherent enzyme-mimicking activity is due to Au, Ag, and Pt, along with other transition metals. Moreover, the nanomaterials exhibit excellent enzyme-mimicking activity when composited with other materials. Therefore, this paper focuses on composite nanozymes with simulated peroxidase activity that have been prepared using noble metals such as Au, Ag, and Pt and other transition metal nanoparticles in recent years. Their simulated enzymatic activity is utilized for biomedical applications such as glucose detection, cancer cell detection and tumor treatment, and antibacterial applications.

Advances in the application of metal oxide nanozymes in tumor detection and treatment.

Natural enzymes play an important role to support the regular life activities of the human body. However, the application conditions of natural enzymes are harsh and there are limitations in their use. As artificial enzymes, nanozymes possess the substrate specificity of natural enzymes. Due to the advantages of low cost, good stability and strong catalytic properties, nanozymes hold a wide range of applications in the fields of sensing, chemical, food and medicine. Some of the more common ones are noble metal nanozymes, metal oxide nanozymes and carbon-based nanozymes. Among them, metal oxide nanozymes have attracted much attention because of their decent fixity, exceedingly good physicochemical properties and other advantages. Today, malignant tumors pose a great danger to the human body and are a serious threat to human health. However, traditional treatments have more side effects, and finding new treatment modalities is particularly important for tumor treatment. For example, enzyme therapy can be used to catalyze reactions in the body to achieve tumor treatment. Nanozymes can exert enzymatic activity and effectively treat malignant tumors through catalysis and synergy, and have made certain progress. This paper reviews the detection and application of metal oxide nanozymes in tumor detection and treatment in recent years and provides an outlook on their future application and development.

Multiple signal-enhanced electrochemiluminescence aptamer sensors based on carboxylated ruthenium (II) complexes for acetamiprid detection.

BACKGROUND: Rapid and sensitive detection for acetamiprid, a kind of widely used neonicotinoid insecticide, is very meaningful for the development of modern agriculture and the protection of human health. Highly stable electrochemiluminescence (ECL) materials are one of the key factors in ECL sensing technology. ECL materials prepared by porous materials (e.g., MOFs) coated with chromophores have been used for ECL sensing detection, but these materials have poor stability because the chromophores escape when they are in aqueous solution. Therefore, the development of highly stable ECL materials is of great significance to improve the sensitivity of ECL sensing technology. RESULTS: In this work, by combining etched metal-organic frameworks (E-UIO-66-NH2) as carrier with Tris(4,4'-dicarboxylic acid-2,2'-bipyridine)Ru(II) chloride (Ru(dcbpy)32+) as signal probe via amide bonds, highly stable nanocomposites (E-UIO-66-NH2-Ru) with excellent ECL performance were firstly prepared. Then, using MoS2 loaded with AuNPs as substrate material and co-reactant promoter, a signal off-on-off ECL aptamer sensor was prepared for sensitive detection of acetamiprid. Due to the excellent catalytic activity of E-UIO-66-NH2-Ru and MoS2@Au towards K2S2O8, the ECL signals can be enhanced by multiple signal enhancement pathways, the prepared ECL aptamer sensor could achieve sensitive detection of acetamiprid in the linear range of 10-13 to10-7 mol L-1, with the limit of detection (LOD) of 2.78ⅹ10-15 mol L-1 (S/N = 3). After the evaluation of actual sample testing, this sensing platform was proven to be an effective method for the detection of acetamiprid in food and agricultural products. SIGNIFICANCE AND NOVELTY: The E-UIO-66-NH2-Ru prepared by linking Ru(dcbpy)32+ to E-UIO-66-NH2 via amide bonding has very high stability. The synergistic catalytic effect of MoS2 and AuNPs enhanced the ECL signal. By exploring the sensing mechanism and evaluating the actual sample tests, the proposed signal "on-off" ECL sensing strategy was proved to be an effective and excellent ECL sensing method for sensitive and stable detection of acetamiprid.

Ferroptosis in renal fibrosis: a mini-review.

Ferroptosis is a novel form of programmed cell death that is iron-dependent and distinct from autophagy, apoptosis, and necroptosis. It is primarily characterised by a decrease in glutathione peroxidase 4 (GPX4) activity, or by the accumulation of lipid peroxidation and reactive oxygen species (ROS). Renal fibrosis is a common pathological change in the progression of various primary and secondary renal diseases to end-stage renal disease and poses a serious threat to human health with high morbidity and mortality. Multiple pathways contribute to the development of renal fibrosis, with ferroptosis playing a crucial role in renal fibrosis pathogenesis due to its involvement in the production of ROS. Ferroptosis is related to several signalling pathways, including System Xc-/GPX4, abnormal iron metabolism and lipid peroxidation. A number of studies have indicated that ferroptosis is closely involved in the process of renal fibrosis caused by various kidney diseases such as glomerulonephritis, renal ischaemia-reperfusion injury, diabetic nephropathy and renal calculus. Identifying the underlying molecular mechanisms that determine cell death would open up new insights to address a therapeutic strategy to renal fibrosis. The review aimed to browse and summarise the known mechanisms of ferroptosis that may be associated with biological reactions of renal fibrosis.

A novel nanoprobe for visually investigating the controversial role of miRNA-34a as an oncogene or tumor suppressor in cancer cells.

MiRNA-targeted therapy has become a hot topic in current cancer research. The key to this treatment strategy is to clarify the specific role of miRNA in cancer. However, the roles of some miRNAs acting as oncogenic or tumor suppressors are still controversial, which are influenced by different tumor types, even in the same cancer type. Hence, we designed a novel fluorescent nanoprobe based on polydopamine nanoparticles (PDA NPs) for simultaneously detecting caspase-3 and miRNA-34a within living cells. The specific role of miRNA-34a in different cancer cells could be further identified by studying the expression alterations of caspase-3 and miRNA-34a. Confocal imaging indicated that miRNA-34a indeed acted as a tumor suppressor in anticancer drug-treated MCF-7 and HeLa cells, where the effect of miRNA-34a remains controversial. The designed nanoprobe can offer a promising approach to ascertain the oncogenic or tumor-suppressing role of miRNA in different cancer cells with a simple visualization method, which has valuable implications for exploring the practicability of precision therapy focused on miRNA and evaluating the efficacy of new miRNA-targeted anticancer medications.

Magnetic photoelectrochemical sensor array utilizing addressing sensing strategy for simultaneous detection of amyloid-ß 42 and microtubule-associated protein tau.

The accurate diagnosis of diseases can be improved by detecting multiple biomarkers simultaneously. This study presents the development of a magnetic photoelectrochemical (PEC) immunosensor array for the simultaneous detection of amyloid-ß 42 (Aß) and microtubule-associated protein (Tau), which are markers for neurodegenerative disorders. A metal-organic framework (MOF) derivative, Fe2O3@FeS2 magnetic composites with exceptional photoelectric and ferromagnetic properties was synthesized while preserving the original structure and advantages. Thus, the immunoassembly process of the sensor can be carried out in homogeneous solution and recovered by magnetic separation. For simultaneous detection, a chip is divided into multiple independent sensing sites, which have the same preparation and detection environment, allowing for the implementation of a self-calibration method. The sensor array demonstrates considerable detection ranges of 0.01-100 ng mL-1 for Aß and 0.05-100 ng mL-1 for Tau, with low detection limits of 2.1 pg mL-1 for Aß and 7.9 pg mL-1 for Tau. The PEC sensor array proposed in this study exhibits exceptional stability, selectivity, and reproducibility, providing a new method for detecting multiple markers.