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At least 19 recordsLinked to original sources
PubMed2026

Gravity-driven millifluidic platform for magnetic solid-phase extraction of Enterocytozoon hepatopenaei DNA from complex shrimp hepatopancreas.

Effective detection of Enterocytozoon hepatopenaei (EHP) in aquaculture is currently hindered by the lack of field-deployable extraction methods capable of processing complex, inhibitor-rich hepatopancreatic tissue. This study presents a gravity-driven millifluidic platform for the rapid extraction of EHP genomic DNA using an optimized, surfactant-compatible magnetic solid-phase extraction (MSPE) chemistry. Utilizing 5% PEG 8000 and 2.0 M NaCl, the platform facilitates the selectively capture of DNA from inhibitor-rich crustacean lysates. The 3D-printed device employs a tilting rocking plate to generate passive, gravity-driven flow, maintaining homogeneous magnetic bead suspension and maximizing solid-phase capture efficiency without external pumps. The integrated platform achieved a DNA yield of 2804.33 ± 15.31 ng/μL, a 5.9-fold increase over manual magnetic bead extraction. TaqMan quantitative PCR (qPCR) validation targeting the EHP SSU rRNA gene was developed. Using a standard curve spanning 101 to 107 plasmid copies (Ct = -3.611 log10 [copy] + 42.309, R2 = 0.998, amplification efficiency 89.2%), the on-chip MSPE achieved a validated analytical limit of detection (LOD) of 1 spore per reaction (100% detection rate, n = 21), whereas a commercial CTAB-based DNA extraction kit failed to achieve a validated LOD even at 10 spores (85.7%, 18/21). Nested PCR targeting the SWP gene was employed for field evaluation. A pilot study across two cohorts (N = 40) demonstrated consistent detection of confirmed EPH-positive cases; however, the small sample size precludes definitive diagnostic accuracy claims. With a total processing time under 30 min, this platform provides a high-efficiency extraction module. Future work will couple the device with isothermal amplification (e.g., LAMP or RPA) to realize a sample-to-answer system for resource-limited aquaculture.

Aquaculture diagnostics↗
PubMed2026

Liquid biopsy-based detection of circulating and exfoliated cholangiocarcinoma tumor cells from blood and bile using heparan sulfate octasaccharides on integrated microfluidic systems.

Early diagnosis of cholangiocarcinoma (CCA) remains challenging because existing diagnostic approaches often lack sufficient sensitivity for reliable detection of early-stage disease. Circulating tumor cells (CTCs) in blood and exfoliated tumor cells (ETCs) in bile represent valuable targets for liquid biopsy-based detection; however, their low abundance and the complexity of clinical sample analysis pose substantial technical challenges for reliable enrichment and identification. Herein, we present a reproducible workflow for isolating and identifying CCA tumor cells from blood for CTCs and bile for ETCs using synthetic cell-surface heparan sulfate (HS) octasaccharide-functionalized magnetic beads (MBs) on integrated microfluidic systems. The method combined sample pre-processing, magnetic bead-based enrichment, controlled low-shear mixing and immunofluorescence-based identification into a unified workflow compatible with distinct clinical sample types. Key operational parameters, including MB concentration, mixing frequency, and pressure settings, were detailed to facilitate consistent performance. Using this workflow, tumor cell capture rates of approximately 70% in bile (for ETCs) and blood (for CTCs) were achieved, with a total processing time of 60-90 min per sample under clinically relevant low-abundance conditions. The platform enables reliable detection of as few as 1 tumor cell per mL of blood or bile. This method provides a practical and adaptable strategy for glycosaminoglycan-mediated liquid biopsy applications and may be extended to other tumor-cell enrichment workflows involving heterogeneous cell-surface interactions.

Humans↗
PubMed2026

A Rapid Poly(ethylene glycol)-Assisted Magnetic Isolation Approach for High-Throughput Extracellular Vesicle Isolation and Subsequent Biomarker Analysis.

Extracellular vesicles (EVs) are crucial mediators of intercellular communication and have the potential to serve as biomarkers for disease diagnosis and therapeutic monitoring. However, most EV isolation methods often require large sample volumes and specialized instruments or involve trade-offs between purity, yield, cost, and scalability. We developed MagPEG, a workflow that combines poly(ethylene glycol) (PEG)-mediated EV aggregation with magnetic beads to provide a simple, reproducible alternative to ultracentrifugation, size-exclusion chromatography, and commercial precipitation kits. Our optimization experiments clarified the PEG concentration, ionic strength, and bead surface chemistry that collectively influence EV aggregation, capture efficiency, and contaminant coprecipitation, allowing us to define conditions that improve purity while maintaining high recovery. Compared with commonly used methods, MagPEG produced EVs with comparable size distribution, EV markers, and proteomic profiles while relying only on standard laboratory supplies. A key feature of the platform is that EVs and EV-associated DNA, RNA, and proteins can be sequentially extracted from the same bead-bound material, reducing sample loss and hands-on time and enabling multiomic analysis for limited clinical or small animal samples. MagPEG is compatible with downstream applications including proteomics, bead-based assays, and miRNA quantification. When applied to human serum, the method supported high-throughput EV proteomic profiling and enabled the identification of Alzheimer's disease-associated protein signatures, illustrating its utility for biomarker discovery. Overall, our results establish MagPEG as a powerful, rapid, scalable, and high-throughput solution for translational applications in biomarker discovery.

Polyethylene Glycols↗
PubMedDate not supplied

[Enzyme-immunoassay of grass-pollen and mites antibodies in rabbit antisera on magnetic polyacrylamide agarose beads (author's transl)].

Complex antigens were coupled to polyacrylamide agarose beads which had been made magnetic with iron oxide. Those beads were then used in an enzyme-immunoassay for quantitation of specific antibodies to grass-pollen and mites in rabbit antisera. The results obtained by a direct or an inhibition technique proved the specificity of this assay towards homologous antigens. Moreover, cross-reactions between the various species of grass-pollen could be shown. One advantage of this simple method is that it may avoid use of radioactive compounds.

Animals↗
PubMed2026

An RPA-assisted homogeneous electrochemical DNA sensor for on-site eDNA detection toward early warning of crown-of-thorns starfish outbreaks.

Crown-of-thorns starfish (COTS) outbreaks seriously threaten coral reef ecosystems, while conventional monitoring approaches are time-consuming and often lack sufficient sensitivity for early warning. Existing electrochemical DNA sensors usually require complex electrode-surface immobilization procedures, which can lead to uneven probe distribution, significant steric hindrance, and poor stability. Meanwhile, the low concentration of environmental DNA (eDNA) in marine environments further complicates detection. To overcome these challenges, this study developed a homogeneous electrochemical DNA sensor assisted by recombinase polymerase amplification (RPA) for COTS eDNA detection. Target DNA was first amplified by RPA, and the amplification products were then hybridized in solution with capture probe (CP)-modified magnetic beads (MB) and biotin-labeled signal probe (SP) to form sandwich-structured MB complexes. These complexes were subsequently magnetically enriched and immobilized on the electrode surface for electrochemical signal readout. Under optimized conditions, the sensor displayed a linear response to COTS genomic DNA from 3.77 fg/μL to 1 ng/μL, with an LOD of 2.02 fg/μL and an LOQ of 3.77 fg/μL. The sensor was applied to Xisha Islands samples, and the results agreed with droplet digital PCR (ddPCR) (P > 0.05), demonstrating its potential for sensitive and reliable on-site COTS eDNA detection.

Animals↗
PubMed2026

High-Purity Monovalent Functionalization of Carbon Nanotubes.

Single-walled carbon nanotubes (SWCNTs) show promise for probing molecular interactions at single-molecule resolution, yet generating SWCNT populations bearing a single defined functional tag remains challenging because surface functionalization is inherently stochastic. Here, we present a batch-scale strategy to produce predominantly singly tagged SWCNTs by leveraging the stochastic adsorption of single-stranded DNA (ssDNA). Specifically, SWCNTs are dispersed using a mixture of unmodified ssDNA (um-ssDNA) and a minor fraction of modified ssDNA (m-ssDNA) carrying an affinity handle. We developed a probabilistic ssDNA-SWCNT binding model that predicts the distribution of m-ssDNA per nanotube as a function of the input minor-strand fraction p = m-ssDNA/total ssDNA, enabling selection of conditions that maximize single-tag purity. Using magnetic-bead capture via a biotin affinity interaction and subsequent release, we isolate SWCNTs with 97.6% predicted single-tag purity at 2% recovery. Single-molecule fluorescence imaging further supports predominantly single-label occupancy under the model-selected conditions. Thus, this approach provides a general route to SWCNTs bearing a single molecular handle for downstream conjugation and assembly, supporting diverse future applications in SWCNT-based nanotechnologies.

Nanotubes, Carbon↗
PubMed2026

PdIr bimetallic nanozyme engineered metal-organic frameworks integrated dual-mode sensor toward Stx2 detection in food.

Shiga toxin II (Stx2) has attracted extensive attention due to its toxicity and pathogenicity, making the development of sensitive detection methods urgent. This study constructed a dual-mode sensing platform for the sensitive detection of Stx2 in food. Composite material UIO-66@PdIr with peroxidase-like activity and fluorescent properties was synthesized and combined with cDNA as the signal probe, while aptamer-modified magnetic beads served as the capture probe. Specific binding of Stx2 to the aptamer triggered the release of the signal probe, enabling colorimetric and fluorescence signal readout. The colorimetric mode showed a linear range of 0.05-100 ng/mL with an LOD of 0.039 ng/mL, and the fluorescence mode exhibited 0.01-1000 ng/mL with an LOD of 0.0097 ng/mL. Additionally, this method was successfully applied to the detection of Stx2 in food, and the recovery rates were 94.33% ∼ 102.20%. It indicated that the constructed sensor holds great practical potential for Stx2 detection.

Food Contamination↗
PubMed2026

An enhanced multisegment RT-PCR method for influenza A virus sequencing: Improved performance and reduced preparation time over traditional methods.

Influenza A viruses (IAVs) remain a major global health threat, affecting both human and animal populations. Whole-genome sequencing is essential for monitoring viral evolution, zoonotic transmission, and emerging variants. However, conventional RT-PCR methods often result in incomplete gene coverage, amplification biases, and reduced sequencing accuracy, particularly in clinical samples. We developed a robust In-house method for IAV full-genome sequencing using the Oxford Nanopore Technologies (ONT) long-read sequencing platform. This method integrates an in-house multisegment Reverse Transcription PCR (RT-PCR) method with a streamlined 2-pool primer design targeting all eight IAV gene segments. RNA extracted from clinical and stock virus samples was reverse-transcribed and amplified using Superscript IV-based chemistry, followed by magnetic bead purification to ensure high-quality amplicons. Sequencing libraries were prepared with the Native Barcoding Kit 24 (SQK-NBD114.24) and sequenced on R10.4.1 flow cells on the MinION MK1C device. Data analysis using the Iterative Refinement Meta-Assembler (IRMA) confirmed improved read depth, uniform coverage, and complete genome recovery. Compared to conventional methods, our In-House Multisegment 2-Pool (IH-MS2P) RT-PCR method generated higher numbers of matched read counts, minimized chimeric artifacts, and delivered superior genome coverage across human, swine, and avian isolates. This optimized RT-PCR method provides a high-performance, time-efficient, and portable solution for influenza genomics, demonstrating robust applicability even with clinical samples of low RNA yield.

Influenza A virus↗
PubMed2026

Benchmarking DNA extraction protocols across use cases for culture-independent Nanopore metagenomics.

Oxford Nanopore Technologies (ONT) sequencing offers several advantages for metagenomics, including long reads, rapid turnaround, low upfront cost, scalability and portability. However, for ONT metagenomics, DNA yield, quality and integrity are important considerations when selecting an extraction method. Many metagenomic extraction methods use harsh lysis conditions to extract a wide range of species and provide an accurate community composition, but these conditions can compromise DNA fragment length. Therefore, extraction methods for ONT metagenomics must balance DNA shearing and recovery with representative community lysis. We systematically evaluated DNA extraction methods for ONT metagenomic sequencing using a use case-oriented framework. Among nearly 50 extraction methods screened, 7 were selected for detailed comparison based on suitability for metagenomics, variation in methodology, availability, cost and processing time: Norgen BioTek Corp's Stool DNA Isolation (NG), Zymo Research's ZymoBIOMICS Quick-DNA HMW MagBead (ZMG), Qiagen's DNeasy Blood and Tissue (QBT), Macherey-Nagel's NucleoMag DNA Microbiome (MN), Zymo Research's ZymoBIOMICS DNA Mini Prep (ZMI), Qiagen's DNeasy PowerSoil/QIAamp PowerFecal Pro (PS) and Qiagen's QIAamp Fast DNA Stool Mini (QIA). Methods were tested using Zymo Research's ZymoBIOMICS Microbial Community Standard (MCS), a matrix-free mock community with known composition. DNA extracts were sequenced on an ONT PromethION using the Rapid Barcoding Kit, except QIA due to insufficient DNA yield. Metrics for the method, DNA extracts, sequencing and genomes were evaluated, revealing trade-offs between methods. The two magnetic bead methods, MN and ZMG, produced the highest mean read length N50 values (13.9 and 16.5 kb, respectively) but showed apparent community compositions skewed towards Gram-negative bacteria. In contrast, ZMI and PS maintained a community composition close to expected, with reduced mean read length N50 values (4.5 vs. 7.5 kb). Performance across various metrics is presented in the context of the following use cases: maximizing genome coverage and assembly completeness, preserving composition accuracy, targeting specific species and limiting required resources (equipment, time or budget). The metrics and use case considerations presented offer practical guidance for informed selection of DNA extraction methods for ONT metagenomics. For accurate community composition, ZMI or PS are recommended, while PS and ZMG perform best at maximizing genome coverage and assembly completeness. NG and QBT may be the most economical options, though performance trade-offs were observed. Finally, PS may be the preferred method for time-sensitive diagnostic or field applications.

Metagenomics↗
PubMed1978

Magnetically responsive polyacrylamide agarose beads for the preparation of immunoabsorbents.

Glutaraldehyde-activated magnetically responsive polyacrylamide agarose beads have been employed to bind bovine serum albumin and human, sheep and rabbit IgG. These were tested for their effectiveness as immunoabsorbents and were found to allow isolation of pure antibodies in high yields. The use of magnetically responsive beads as the solid support in immunoabsorption procedures renders isolation of antibodies easy and rapid.

Animals↗
PubMed1978

Magnetic enzyme immunoassay for measuring human IgE.

This paper reports a solid-phase sandwich technique for the assay of human IgE using anti-IgE antibodies bound to magnetic polyacrylamide-agarose beads. Following this technique, IgE to be determined is allowed to bind to the magnetic beads bearing the anti-IgE antibodies. After washing on a magnetic rack, the beads are incubated with enzyme-labeled antibodies, washed again, and then the enzyme activity associated with the beads is measured. The use of magnetic polyacrylamide-agarose beads and of enzyme-labeled antibodies makes the measurement of IgE in human sera easy to perform, safe, and reproducible. This procedure allows the measurement of IgE concentration in serum containing more than 2 IU/ml. The values obtained from 104 human sera closely corresponded to those obtained by radioimmunoassay (correlation coefficient, r = 0.9751).

Humans↗
PubMed1978

Magnetic enzyme immunoassay of anti-grass pollen specific-IgE in human sera.

This paper reports a magnetic solid-phase sandwich enzyme immunoassay for specific IgE antibodies in human sera. Crude extracts of grass pollen bound to magnetic polyacrylamide agarose beads were mixed with human serum to be tested. After washing in a magnetic rack, the beads were incubated with the glucose-oxidase-labelled sheep anti-IgE. The enzyme activity associated with the beads was measured by colorimetric assay. Results obtained from sixty-one human sera, as measured by the magnetic enzyme immunoassay, gave a linear correlation coefficient of 0.98 with the values as determined by radio-immunoassay. This procedure, which allows the grass pollen specific IgE in human sera, to be measured, is easy to perform, reproducible and may avoid the use of radioactive compounds.

Antibody Specificity↗
PubMed2026

Towards a Robust cell-free DNA Isolation Protocol for NGS Applications in a Clinical Molecular Diagnostics Setting.

Cell-free DNA (cfDNA), released from apoptotic and necrotic cells into body fluids, is a non-invasive source of genetic information for disease prediction, diagnosis, and monitoring. However, its low abundance makes cfDNA highly susceptible to various pre-analytical influences, potentially increasing high molecular weight (HMW) or genomic DNA (gDNA) compromising downstream cfDNA analyses. This study evaluated the impact of different cfDNA-stabilizing blood collection tubes (BCT; Cell-Free DNA BCT, Streck; S-Monovette cfDNA Exact, Sarstedt) stored at room temperature for 1, 5, or 10 days, prior to plasma isolation using different isolation methods (magnetic bead-based or silica column-based) on cfDNA stability and yield. DNA quantity and quality were assessed by fluorometric quantification, automated fragment analysis, and gene-specific quantitative PCR. Streck-based workflows maintained stable cfDNA yields and characteristic mononucleosomal fragmentation profiles across all storage times. In contrast, Sarstedt tubes showed reduced cfDNA concentrations after 5 days and a pronounced increase at 10 Days, accompanied by high-molecular weight DNA patterns consistent with white-blood cells (WBC) lysis. These trends were largely independent of the extraction method. Overall, the results demonstrate that blood collection tube chemistry critically influences cfDNA integrity during delayed processing. Streck tubes, particularly when combined with silica column-based isolation method, provided the most robust and reproducible workflow for routine molecular diagnostics, whereas Sarstedt tubes produced physiologically implausible results after extended storage.

blood collection tubes↗
PubMed2025

Unlocking Zeptomolar Single-Molecule Detection by Synergizing Digital Microfluidics and Digital CRISPR.

Accurate diagnosis relies on the highly sensitive and quantitative detection of multiple immune-related biomarkers. However, current detection methods still face significant limitations in sensitivity, specificity, and background signal control. Here, we introduce DDA (Dual-Digital immunoAssay), a fully automated, universal immunoassay platform that synergizes digital microfluidics with digital Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)-based amplification. This "dual-digital" strategy pushes the detection limit into the zeptomolar (zM) regime, enabling unprecedented sensitivity for single-molecule analysis. The DDA platform is built upon a digital microfluidic microwell array chip, integrating magnetic bead-based immunocapture with RNA-guided CRISPR/Cas13a signal amplification. This system enables a fully automated, "sample-in, answer-out" workflow. By systematically optimizing the entire process, DDA significantly reduces background noise and enhances detection sensitivity, achieving a limit of detection (LOD) down to 100 zM for key protein biomarkers. This represents a >100-fold improvement over leading commercial ultrasensitive assays. With single-molecule resolution and full automation, DDA provides a robust solution for the precise quantification of low-abundance immune biomarkers. As a proof-of-concept, we demonstrate its ability to accurately quantify key heart-failure-associated biomarkers, including NT-proBNP (LOD: 1 aM), IL-6 (LOD: 1.5 aM), and TNF-α (LOD: 2.5 aM), directly in complex serum samples. This platform holds great promise for automated multibiomarker screening and risk assessment, showcasing its powerful potential for the early diagnosis of major diseases such as cardiovascular diseases, cancers, neurodegenerative disorders, and infectious diseases.

Humans↗
PubMedDate not supplied

Microsomal mixed-function amine oxidase. Oxidation products of piperazine-substituted phenothiazine drugs.

Oxidation products of fluphenazide, thioproperazine, and trifluoperazine obtained in reactions catalyzed by homogeneous preparations of the microsomal mixed-function amine oxidase have been isolated and identified. Approximately 0.5 g of metabolite of each piperazine-substituted phenothiazine drug was prepared in reactors containing, as catalyst, the purified oxidase covalently attached to glass beads. Nuclear magnetic resonance spectra of the isolated products indicated that with all three substrates the enzyme preferentially catalyzes N-oxidation of the piperazine nitrogen furthest from the phenothiazine nitrogen atom. The enzyme-catalyzed oxidation is quite specific and oxidation of the sulfur or nitrogen atoms in the phenothiazine ring could not be detected. Concentrations of piperazine-substituted phenothiazines required to half-saturate the amine oxidase were in the micromolar range and at pH 8.3 and 37 degrees C, all those tested were oxidized at approximately 2 mumol/min/mg of enzyme. Kinetic constants for the piperazine-substituted phenothiazines were very similar to those obtained with phenothiazines containing a dimethylaminopropyl sidechain.

Animals↗
PubMed1979

Antibody-dependent cellular cytotoxicity against tumor cells. II. The promonocyte identified as effector cell.

Macrophage precursor cells were cultured from the bone marrow of mice in a liquid culture system in the presence of conditioned medium. To separate their different maturation stages, they were passed through a discontinuous Ficoll density gradient, treated with iron plus magnet or passed through glass bead columns. The different maturation stages have been tested for their function in antibody-dependent cellular cytotoxicity (ADCC) against tumor target cells and in lymphokine-induced macrophage-mediated cytotoxicity. It is shown that the promonocyte, a nonadherent, nonphagocytic precursor cell, is a highly potent cytotoxic effector cell against antibody-coated tumor targets but is totally inactive as an effector cell in lymphokine-induced macrophage-mediated cytotoxicity. In contrast, in the lymphokine-induced macrophage-mediated cytotoxicity the cytotoxic effector cell is a mature macrophage. Thus, ADCC seems to be a function of the macrophage precursor promonocytes, whereas lymphokine-induced cytotoxicity is performed by mature macrophages. The relationship of promonocytes and killer (k) cells in ADCC against tumor targets is discussed.

Animals↗
PubMed2026

Artificial Intelligence and Machine Learning Applications in Fibromuscular Dysplasia: Transforming Diagnosis, Risk Stratification, and Clinical Decision-Making.

Fibromuscular dysplasia (FMD) is a non-atherosclerotic vascular disorder with heterogeneous presentations, making diagnosis and management highly dependent on imaging and clinical expertise. This narrative review examines how artificial intelligence (AI) and machine learning (ML) are transforming FMD care. AI-enhanced imaging, particularly convolutional neural network-based analysis, improves detection of the characteristic "string-of-beads" pattern on CT angiography, magnetic resonance angiography, and ultrasound, although FMD-specific validation remains limited. ML models facilitate risk stratification, prediction of disease progression, and early identification of complications such as aneurysms and stroke by integrating clinical, imaging, and genomic data. AI-driven clinical decision support systems further enable personalized treatment selection through pharmacogenomic insights and robot-assisted interventions. Despite promising real-world applications, challenges persist, including limited large-scale datasets, workflow integration, regulatory barriers, and algorithmic bias affecting underrepresented populations. Future advances in explainable AI, federated learning, and digital health integration may enable a shift toward predictive, patient-centered FMD management.

Humans↗