MicroRNA-155 (miR-155) is a key oncogenic driver in lung cancer, making sensitive in situ imaging essential for early diagnosis. Conventional catalytic hairpin assembly (CHA)-based methods suffer from poor probe stability, low cellular uptake, and nonspecific signal leakage. To address these issues, we developed a dual-DNA nanoballmediated three-dimensional CHA (DNB-3DCHA) system for in situ imaging of miR-155 in living lung cancer cells. Two functionalized DNA nanoballs anchor the two CHA hairpin probes (H1 and H2) on their surfaces, respectively. After endocytosis, target miR-155 specifically triggers the 3D-CHA reaction on nanoball surfaces, leading to exponential fluorescence amplification. This "split-loading, activation-after-entry" strategy decouples probe delivery from activation, minimizing background leakage, while the rigid nanoball architecture provides robust nuclease protection. Using lung cancer cells as a model, we demonstrate that DNB-3DCHA enables high-contrast, spatiotemporally controlled in situ imaging of miR-155 with excellent specificity and signal-to-noise ratio, offering a promising tool for cancer diagnostics.

Lycium ruthenicum polysaccharides (LRP) are known to possess antioxidant effects. However, a systematic evaluation across chemical, cellular, and in vivo models have been lacking. The underlying metabolomic mechanisms also remain unexplored. This study systematically evaluated the antioxidant effects of LRP through in vitro assays, H₂O₂-induced AML12 hepatocytes, and liver tissue from mice, supplemented by untargeted metabolomic analysis of cell extracts to explore LRP’s antioxidant mechanisms. Results showed that LRP possessed significant oxygen radical absorbance capacity and potent scavenging activity against ABTS•+, DPPH•, and •OH radicals in vitro. In AML12 cells, LRP increased activities of antioxidant enzymes, including catalase (CAT), superoxide dismutase (SOD), and glutathione reductase (GSH-Px), while effectively reducing intracellular reactive oxygen species (ROS) and malondialdehyde (MDA) levels (P<0.05). In mouse liver tissues, LRP may have slightly improved SOD and CAT levels while decreasing MDA levels (P>0.05). Furthermore, untargeted metabolomics revealed that LRP attenuated oxidative damage by modulating metabolic pathways, particularly glutathione metabolism, the tricarboxylic acid (TCA) cycle, and amino acid metabolism. These findings confirm the significant antioxidant potential of LRP, supporting its promise as a functional food ingredient.

MicroRNAs (miRNAs) are well-established biomarkers for tumor diagnosis and monitoring. Herein, we report a novel biosensing platform by engineering a structure-initiated variant of catalytic hairpin assembly (VCHA) that coordinates with strand displacement amplification (SDA) to drive cascade amplification for CRISPR/Cas12a-based detection. This system employs three hairpin probes which, upon recognizing the target miRNA, self-assemble into a key 5'-end dangling three-way conjugate (5'-DTC) structure. This structure serves as the exclusive trigger, simultaneously propagating the VCHA cycle and priming the SDA process through the coordinated action of polymerase and nicking enzyme. Consequently, VCHA and SDA operate synergistically within a unified circuit, generating abundant single-stranded activator DNA (acDNA) products. These acDNA molecules then activate the trans-cleavage activity of CRISPR/Cas12a, yielding a significantly amplified fluorescence readout. The VCHA-SDA/Cas12a platform demonstrated excellent performance for miRNA-155 detection, achieving a broad dynamic range from 1 pmol/L to 10 nmol/L with an ultra-low detection limit of 0.166 pmol/L. Furthermore, the platform successfully quantified miRNA levels in clinical plasma specimens and various cell lines, confirming its considerable potential as a robust tool for molecular diagnostics and clinical translation.

The CRISPR-Cas12a system has revolutionized nucleic acid detection by leveraging its trans-cleavage activity, yet its full potential remains limited by the use of short linear single-stranded DNA (ssDNA) reporter, which often exhibit restricted signal response and moderate sensitivity. In this study, we demonstrate that Cas12a can efficiently recognize and cleave triple-helix molecular beacons (THMBs), a class of nucleic acid probes that combine a triplex stem with a single-stranded loop. Capitalizing on this finding, we developed TH-CRISPR/Cas12a, a novel biosensing system in which an intramolecular THMB serves as the reporter probe. Applied to the detection of SARS-CoV-2, the system targets conserved regions of the ORF1a/b and N genes. Under identical reaction conditions, the THMB reporter achieved complete Cas12a-mediated trans-cleavage within 20 min, significantly outperforming conventional linear ssDNA probe in both reaction rate and signal amplitude. Without any target amplification, the platform attained a detection limit of 109 fM using dual genes as targets. In pseudovirus assays, it detected concentrations as low as 25 copies/mL. This work establishes THMBs as a superior class of reporters for CRISPR diagnostics, enabling the development of high-performance detection systems through the rational design of non-canonical nucleic acid structures. Furthermore, it provides a new perspective for the study of the interaction between the CRISPR/Cas system and nucleic acids with non-canonical structures.

The use of pesticides is integral to modern agriculture for managing pests, mitigating diseases, and securing harvest output. As multiple pesticides and their residues can coexist in plant-based products, they may pose synergistic health risks to humans. Thus, the simultaneous detection of such compounds provides a more efficient strategy than single-component analysis for monitoring pesticide residues in food, thereby helping to ensure compliance with food quality and safety regulations. Immunoassay technology is widely employed for pesticide detection owing to its high specificity, sensitivity, portability, and cost-effectiveness. This review systematically covers major multiplex immunoassay strategies, including microarray immunoassays, immunochromatographic assays, flow injection immunoassays, and multi-label immunoassays. It focuses on their application for the simultaneous analysis of pesticide residues in various matrices, such as water and diverse food products including fruits, vegetables, grain, and the processed derivatives. Furthermore, the current challenges and future research trajectories for developing automated, portable, highly sensitive, and high-throughput multiplex detection platforms are discussed.

Background: DNA methylation catalyzed by various DNA methyltransferases (DNA MTases) is one of the important epigenetic regulations in both eukaryotes and prokaryotes. Therefore, the detection of DNA MTase activity is a vital target and direction in the study of methylation-related diseases. Results: In this study, an ultrasensitive and robust strategy was developed for DNA MTase activity sensing based on bifunctional probe propelling multipath strand displacement amplification and CRISPR/Cas12a techniques. First, a bifunctional hairpin probe (bHpDNA) was designed instead of a conventional single-function probe. In the presence of DNA MTase, the bHpDNA was methylated and cleaved by a restriction endonuclease into two independent primers, both of which bind with the templates to trigger strand displacement amplification and produce the active DNA of CRISPR/Cas12a. Second, annealing-assisted binding instead of free diffusion adhesion was used to improve hybridization efficiency between the primers and templates. Finally, the CRISPR/Cas12a system was used to achieve fluorescence signal output to analyze DNA MTase activity. If targets were absent, there was no signal because no primers were released from the bHpDNA. To verify the reliability of the method, two key DNA MTases, Dam and M. SssI, were analyzed, and their limits of detection were 2.458 x 10- 3 and 3.820 x 10-3 U/mL, respectively, which were lower than those of most reported fluorescence methods. Significance: This method was successfully used in the evaluation of DNA MTase inhibitors and the detection of DNA MTase activity in complex biological systems with good recoveries and relative standard deviation at low spiked concentrations (0.1-1 U/mL), which all indicate that this method is an ultrasensitive and robust strategy in DNA MTase activity assay and has great potential in biomedical and clinical detection.

As biomarkers for liquid biopsy, tumor exosomes play a key role in the early tumor diagnosis and postoperative monitoring. However, the accurate and portable detection of exosomes remains a big challenge. Here, a novel lateral flow test strips based on manganese dioxide (MnO2) and aptamer-functionalized fluorescent microspheres (FMs-aptamer) was developed for colorimetry/fluorescence dual-mode sensing of cancer-associated exosomes (using MCF-7 cells derived exosomes as model) in serum samples. Various characterizations (including UV-vis, FTIR, SEM, TEM, DLS, XRD and XPS) were first carried out to demonstrate the successful preparation of test strips. In this work, the size advantage of exosomes is skillfully used to mediate the fluorescence resonance energy transfer (FRET) between FMs (donors) and MnO2 (acceptor), thus a dual-mode output platform was constructed. Comapred to the single-readout test strips, our propsed method could reduce the false positive via recording the change of two different signals. This test strip realized sensitive and accurate detection of MCF-7 exosomes, with a detection limit of 2.5×103 particles/mL. Importantly, the platform enables direct and rapid detection of cancer exosomes in serum samples without tedious sample pretreatment process, showing its great potential for point-of-care tests.

Cell surface receptors play a key role in intracellular signaling, and their overexpression and activation are among the drivers of multiple diseases. Selective inhibition of cell surface receptors is important for regulating intracellular signaling pathways and cell behavior. Here, we design engineered aptamers to selectively inhibit receptor function. In this strategy, the aptamer specifically recognizing the extracellular structural domain of the EGFR, was conjugated to an adamantane moiety through linking arms of various lengths in order to obtain better performances toward EGFR. These interactions inhibit EGFR dimerization, thereby impeding the activation of downstream signaling pathways. It is shown that the adamantane-modified aptamers exhibit superior inhibition of downstream effector proteins relative to the unmodified aptamers. The optimal inhibitory effect was observed with a linker arm of 40 T-base in length. Notably, the best-performing adamantane-modified aptamer specifically binds to A549 cells with a dissociation constant (22.6 +/- 4.5 nM) that is approximately 4-fold lower than that of the parent EGFR aptamer (94.4 +/- 21.9 nM). We further combine the use of the adamantane-modified aptamer with that of genistein, a natural isoflavone compound with EGFR tyrosine kinase inhibition activity, to enhance the inhibitory effect on EGFR and its downstream signaling employing a synergistic action. This study is expected to provide a versatile approach for the improvement of existing aptamers obtaining increased selective inhibition of cell surface receptors.

Tetracyclines (TCs) are the most commonly antimicrobial agents that used in livestock production worldwide. It is important to supervise tetracyclines residues in food for environmental monitoring and food safety. In this study, a novel, label-free chemiluminescence (CL) assay without antibody was established. Fe3O4 NPs could facilitate the CL interaction between luminol and H2O2. Interestingly, TCs could enhance the catalytic ability of Fe3O4 NPs and result in a further amplification of the CL intensity. The CL intensity varied linearly with the concentration of tetracycline (TC), oxytetracycline (OTC), chlortetracycline (CTC), and ranging from 10–2400, 10–2800, and 5–2100 nmol/L, respectively; The limits of detection were 4 nmol/L for TC, 6 nmol/L for OTC, and 2 nmol/L for CTC. This CL strategy was applied successfully in testing three TCs residues in milk, eggs and honey samples with more sensitive results, which provided an alternative strategy for monitoring the correct use of TCs.

Background: With the advent of personalized medical approaches, precise and tailored treatments are expected to become widely accepted for the prevention and treatment of diabetes. Paper-based colorimetric sensors that function in combination with smartphones have been rapidly developed in recent years because it does not require additional equipment and is inexpensive and easy to perform. In this study, we developed a portable, low-cost, and wearable sweat-glucose detection device for in situ detection. Results: The sensor adopted an integrated biomimetic nanoenzyme of glucose oxidase (GOx) encapsulated in copper 1, 4-benzenedicarboxylate (CuBDC) (GOx@CuBDC) through a biomimetic mineralization process. CuBDC exhibited a peroxide-like effect, cascade catalytic effect with the encapsulated GOx, and increased the enzyme stability. GOx@CuBDC and 3,3,5,5-tetramethylbenzidine were combined to form a hybrid membrane that achieved single -step paper-based glucose detection. Significance and novelty: This GOx@CuBDC-based colorimetric glucose sensor was used to quantitatively analyze the sweat-glucose concentration with smartphone readings. The sensor exhibited a good linear relationship over the concentration range of 40 - 900 mu M and a limit of detection of 20.7 mu M (S/N = 3). Moreover, the sensor performed well in situ monitoring and in evaluating variations based on the consumption of foods with different glycemic indices. Therefore, the fabricated wearable sweat -glucose sensors exhibited optimal practical application performance.

Due to the high viscosity and low fluidity of crude oil at room temperature, the efficient recovery of offshore oil spills by an environmental friendly way is still a global challenge. Oil-water separation technology is seen as a promising method to solve the problem of oil spills at sea. However, conventional oil-water separation can only recover low-viscosity light oil. Solar energy, as a clean and renewable energy source, is widely applied in many areas because of its natural remarkable, low cost, and eco-friendly properties. Using solar energy as the thermal source, interfacial photothermal oil absorption technology has been developed for the recovery of oil, especially high-viscosity crude oil. This article focuses on the state of art of solar-assisted adsorbents for crude oil cleanup. Here, we will start with an introduction to the wetting mechanism and common photothermal conversion materials; then list various oil-absorbing materials, including sponges, aerogels, and fabrics. Finally, the advantages and disadvantages of photothermal oil-absorbing materials are summarized, and its prospects are outlooked with the intend to serve the researches the advances of future research.

Gene methylation-related enzymes (GMREs) are disfunction and aberrantly expressed in a variety of cancers, such as lung, gastric, and pancreatic cancers and have important implications for human health. Therefore，it is critical for early diagnosis and therapy of tumor to develop strategies that allow rapid and sensitive quantitative and qualitative detection of GMREs. With the development of modern analytical techniques and the application of various biosensors, there are numerous methods have been developed for analysis of GMREs. Therefore, this paper provides a systematic review of the strategies for level and activity assay of various GMREs including methyltransferases and demethylase. The detection methods mainly involve immunohistochemistry, colorimetry, fluorescence, chemiluminescence, electrochemistry, etc. Then, this review also addresses the coordinated role of various detection probes, novel nanomaterials, and signal amplification methods. The aim is to highlight potential challenges in the present field, to expand the analytical application of GMREs detection strategies, and to meet the urgent need for future disease diagnosis and intervention.

Tetracyclines (TCs) are the most commonly antimicrobial agents used in terrestrial food-producing animals. So, it is important to supervise tetracyclines residues in food for correcting the abuse of antibiotics in animals. In this paper, a novel label-free chemiluminescence (CL) assay without antibody was established for three TCs detection utilizing the catalytic ability of ferroferric oxide nanoparticles (Fe3O4 NPs). Fe3O4 NPs could facilitate the CL interaction between luminol and H2O2 due to their enzyme-like activity. Interestingly, TCs could enhance the catalytic ability of Fe3O4 NPs and result in a further amplification of the CL intensity. Under optimal conditions, the CL intensity varied linearly with the concentration of tetracycline (TC), oxytetracycline (OTC), chlortetracycline (CTC), and ranging from 10~2400, 10~2800, and 5~2100 nmol/L, respectively; The limits of detection were 4 nmol/L for TC, 6 nmol/L for OTC, and 2 nmol/L for CTC. This CL strategy was applied successfully in testing three TCs residues in milk, eggs and honey samples with more sensitive results than that of the colorimetric, fluorescence and high-performance liquid chromatography (HPLC) methods, which provided an alternative strategy for monitoring the correct use of TCs.

In recent years, tetracyclines (TCs) is a hot research topic. Herein, we report an interesting discovery using the complexation of oxytetracycline and metal ions. In this study, according to the properties of Fe3O4nanoparticles (Fe3O4NPs) as a nanoenzyme, it can be used to catalyze the oxidation of KI by H2O2to produceI3-,while at the same timeI3-binds to rhodamine 6G (Rh6G) to form a conjoined particle (Rh6G ∼ I3)n, leading to a decrease in the fluorescence intensity of Rh6G. However, in the presence of TCs, Fe3O4NPs have a synergistic effect with TCs, leading to enhanced catalytic activity, as well as better selectivity compared to the activity of other reducing enzymes. Consequently,the fluorescent signal based on a resonance scattering effect between Rh6G andI3-is dependent on the concentration of TCs, thus achieving highly facile and robust detection of TCs. The limits of detection (LOD) of the method were 20 nM, 10 nM and 40 nM for oxytetracycline(OTC), tetracycline(TC) and chlortetracycline(CTC), respectively. Most importantly, the method can be successfully applied to the detection of TCs in milk, eggs, and honey. The recoveries of spiked samples ranged from 83.11 to 118.95%. Thus, a stable, hands-on strategy for the detection of TCs is proposed, which has potential applications in the field of food safety and environmental protection.

目的 探讨维生素D水平与儿童哮喘风险的关系.方法 从以下在线数据库:PubMed、Embase、Web of Science、Scopus、万方、中国知网和维普中检索2015年7月至2023年2月的相关文献,采用STATA 12.0软件进行meta分析.结果 共纳入21项研究,包括17项病例对照研究和4项横断面研究,共包括3 805名儿童,其中2 028名儿童被诊断为哮喘,1 777名为对照儿童.meta分析结果显示,哮喘儿童的血清维生素D水平低于对照组[标准化均数差(SMD)=-1.65,95％CI:-2.23～-1.08,P＜0.001].森林图显示,维生素D缺乏与儿童哮喘的风险增加有关(OR=3.57,95％CI:2.41～5.20,P=0.002).结论 meta分析结果表明,血清维生素D水平与儿童哮喘有关;维生素D缺乏的儿童患哮喘的风险更高.

The abnormal expression of DNA methyltransferase1 (DNMT1) leads to change of genome methylation pattern, which may result in the occurrence and development of cancer. Therefore, the determination of DNMT activity is of great significance for cancer diagnosis and drug screening. In this study, we developed a novel method to detect DNMT1 activity using self-assembly nucleic acid probe signal amplification based on a fluorescence assay. The semi-methylated Biotin-S1'-S2' with sticky ends was fixed to the magnetic beads through the affinity of streptavidin and Biotin. Afterward, pre-prepared poly Tetramethylrhodamine (TAMRA) was added for base complementary pairing with Biotin-S1'-S2' via its sticky end when DNMT1 is present and BssHII shearing is blocked by fully methylated bilayers, thus, the amplified fluorescent signal can be detected. The results showed that the fluorescence intensity of the system was positively correlated with the concentration of DNMT1 in the concentration range of 1–100 nmol/L, and the detection limit was as low as 0.5 nmol/L. The method is simple, highly visualized and successfully applied for the recovery of DNMT1 activity in serum samples. Thus, the method shows great potential for application in clinical diagnosis related to DNMT1.

Novel molecularly imprinted resorcinol-formaldehyde resin nanofibers (MIRF NFs) was prepared using poly -dopamine as an intermediate. With high specific surface area and favorable usability, MIRF NFs presented high efficiency for the solid phase extraction (SPE) of sulfonamides (SAs) in complex animal foods. After optimizing the operating conditions, a new method for SAs quantification coupled with HPLC-MS/MS was developed. By simple water dilution of the solvent extracts, SPE could be carried out. In addition, the eluent could be analyzed directly without any further treatment. The newly developed method was simplified greatly with much fewer sample pretreatment procedures (4 steps). Moreover, much fewer amounts of sample (1.0 g), adsorbent (3.0 mg), organic solvent (1.5 mL) and preparation time (20 min for 24 samples) were needed. The obtained good linearity (R2 > 0.9957), low detection limits (0.01-0.14 mu g kg -1), satisfactory recoveries (83.0 %-112.9 %) and precisions (RSDs < 12.6 %) further proved the feasibility of the method in practical application.

Ferritin plays an important role in regulating the homeostasis of iron in cells by storing/releasing iron. Current methods usually explored the determination of iron content, but in-situ imaging of the iron storage/release from ferritin in cells cannot be achieved. Hence, an engineered self-assembled biomimetic-compartmented nanoprobe (APO@CDs) has been constructed. The protein shell of APO (apoferritin) acted as ion channel module to control iron ions entering/exiting ferritin cavity; the inner core of CDs (carbon dots) acted as signal module for iron ions response. Compared with CDs, the response sensitivity and specificity to iron ions (Fe3+) have been improved by using APO@CDs, and the cytotoxicity was significantly reduced. Additionally, compared with cells containing APO@CDs alone, the normalized fluorescence gray value of Fe3+-treated cells was significantly decreased (0.275), indicating that Fe3+ has effectively entered the ferritin. Furtherly, that of Fe3+-treated cells incubated with deferoxamine (DFO) was significantly enhanced (0.712), showing that Fe3+ was released from ferritin under the mediation of DFO. The results demonstrate that APO@CDs can be successfully applied to in-situ imaging of iron storage/release from ferritin in cells, providing a potential platform for the in-situ dynamic study of the iron storage/release in biomedical field.

Background In this study, we enrolled 862 patients with Crohn’s disease (CD) in China to investigate the correlation between serum vitamin D (SVD) and serum lipids, inflammatory biomarkers, and important clinical parameters. Materials and Methods 25(OH)D was measured by LS/MS/MS. Correlation analysis, chi-square tests, and logistic regression analysis were performed to determine the correlations between vitamin D and potential risk factors when vitamin D levels were lower than 10 ng/mL or 20 ng/mL. Results The incidence of severe vitamin D deficiency (SVD < 10 ng/mL) in patients with CD was significantly higher than that in healthy controls (28.9 vs. 9.5%). Multinomial logistic regression analysis showed that penetrating disease [odds ratio (OR) = 2.18], low levels of high-density lipoprotein cholesterol (HDL) (OR = 1.91), high erythrocyte sedimentation rate (OR = 1.73), and platelet count (PLT) (OR = 2.71) were regarded as predictors of severe vitamin D deficiency, while only PLT (OR = 1.90) and HDL (OR = 1.76) were considered as predictors of mild vitamin D deficiency (SVD 10–20 ng/mL). Conclusion Our results confirm a higher incidence of severe vitamin D deficiency in patients with CD in China and show that vitamin D deficiency could result from the combined effects of penetrating disease, inflammation, and low levels of HDL.