Porous Na-doped g-CN via supramolecular self-assembly for enhanced photocatalytic antibiotic removal and bacterial inactivation.

This study synthesizes dual-modified graphitic carbon nitride (CN) through morphological engineering and Na doping, synergistically enhancing visible-light absorption and charge carrier dynamics. A coral-like Na-doped CN (NaCCN) was fabricated via one-step calcination method, leveraging the self-assembly of melamine and cyanuric acid in NaCl solution. This strategy simultaneously improved the electronic structure of the catalyst skeleton, increasing active sites and boosting electron transfer efficiency.

Sensitive detection of multiplex bacteria based on finger driven microfluidics and recombinase aided amplification.

Foodborne pathogens, such as Salmonella typhimurium, E. coli O157:H7 and Listeria monocytogenes, have seriously threatened human health. To address the issues of traditional bacterial detection methods, such as long time, low sensitivity and complex operation, a versatile finger driven microfluidic chip was elaboratively developed and combined with recombinase aided amplification for fast, sensitive and simple detection of multiplex bacteria.

Dual-functionalized defective metal-organic frameworks for fast and sensitive biosensing of Salmonella.

Accurate screening of pathogenic bacteria is effective to prevent foodborne diseases. In this study, a handheld biosensor was newly developed for sensitive detection of Salmonella inside a pipette tip using immune nickel meshes (INMs) for bacterial enrichment and fluorescent defective metal-organic frameworks with boronic acid (MOFs@B(OH)) for bacterial labeling. First, three INMs were respectively assembled in a 3D-printed conic separator inside a tip.

Two-pot ready-to-use reagents achieved quadruple-signal amplification for the ultra-sensitive biosensing of Salmonella Typhimurium in foods.

The achievement of both ultra-sensitivity and operational simplicity remains a major challenge in the development of nanozymatic biosensors for foodborne pathogen detection. Here, we report a two-pot, ready-to-use nanozymatic colorimetric biosensor that integrates a cascade-based quadruple signal amplification strategy for the rapid detection of Salmonella Typhimurium (S.T.

A Colorimetric Biosensor Integrating Rotifer-Mimicking Magnetic Separation with RAA/CRISPR-Cas12a for Rapid and Sensitive Detection of .

Efficient detection of foodborne bacteria is crucial for ensuring food safety, yet current methods often fall short in balancing speed, accuracy, sensitivity, and cost. This study presents an integrated biosensing platform for the rapid and sensitive detection of in large-volume food samples. The platform incorporates a Rotifer-Mimicking Magnetic Separator (RMMS) that enhances the sample pretreatment by effectively mixing and isolating the bacteria from the sample.

A colorimetric biosensor based on 3D printed spiral mixer and magnetic continuous-flow separation for sensitive detection of Salmonella in centrifuge tubes.

Early screening of foodborne pathogens is effective to prevent food poisoning. In this work, a portable colorimetric biosensor was innovatively developed on a centrifugal tube using a 3D printed spiral mechanical mixer for rapid immune reaction, a 3D printed magnetic field generator for continuous-flow bacterial capture, Au@Pt nanozymes for effective signal amplification, and a smartphone application for accurate image processing. The rapid and efficient mixing of specific antibodies on the magnetic beads and Au@Pt nanozymes with target bacteria was simply achieved through repeated press-and-release actions on the mixer to produce the vortex turbulence in the sample chamber and thus form the magnetic bead-bacteria-nanozyme conjugates.

Tumor-specific liquid metal nitric oxide nanogenerator for enhanced breast cancer therapy.

Nitric oxide (NO) modulates several cancer-related physiological processes and has advanced the development of green methods for cancer treatment and integrated platforms for combination or synergistic therapies. Although a nanoengineering strategy has been proposed to overcome deficiencies of NO gas or small NO donor molecules, such as short half-life, lipophilicity, non-selectivity, and poor stability, it remains challenging to prepare NO nanomedicines with simple composition, multiple functions and enhanced therapeutic efficacy. Herein, we build a liquid metal nanodroplet (LMND)-based NO nanogenerator (LMND@HSG) that is stabilized by a bioreducible guanylated hyperbranched poly(amido amine) (HSG) ligand.

A Smart Single-Loop-Mediated Isothermal Amplification Facilitates Flexible SNP Probe Design for On-Site Rapid Differentiation of SARS-CoV-2 Omicron Variants.

Rapid on-site typing methods for SARS-CoV-2 variants of concern are crucial for its effective surveillance and control. Herein, a smart single-loop-mediated isothermal amplification (ssLAMP) method with the absence of an inner primer but the addition of a swarm primer for differentiation of SARS-CoV-2 Omicron variants is developed. This unique primer design strategy offers greater flexibility in introducing single nucleotide polymorphism (SNP) identification probes and enables multiple detection assays for SARS-CoV-2 Omicron variants including BA.

One-step colorimetric immunosensing of foodborne bacteria using static magnet driven magnetophoretic separation and dual noble metal decorated magnetic nanobeads.

Background: Immunomagnetic separation is essential for screening pathogenic bacteria to prevent food poisoning. However, free immunomagnetic nanobeads (IMNBs) coexist with IMNB-bacteria conjugates (IBCs) after traditional immunomagnetic separation resulting in the infeasibility for IMNBs on IBCs to further act as signal label in bacterial detection. Although we have demonstrated that magnetophoretic separation at a high flowrate could separate IBCs from IMNBs, partial IMNBs were still found with IBCs due to chaotic flows and resulted in inevitable interferences.

Cascaded Gravity-Driven Microfluidic Chip with Tilt-Actuated Siphon Valves for Rapid Detection of Typhimurium.

In recent years, urgent food safety issues have heightened the demand for rapid detection technologies for foodborne pathogens, especially biosensors featuring simplicity, rapidity, and high sensitivity. Yet despite a booming surge in related published studies, commercializing these biosensors remains a constant challenge and persistent objective for researchers. In this study, a gravity-driven microfluidic chip with tilt-actuated siphon valves was developed, integrating silica magnetic beads based nucleic acid separation and recombinase-aided amplification (RAA) detection of Typhimurium by simple operations along with a portable biosensing device.

Bacterial Bioaerosol-Specific Capture and In Situ Detection Using an Immune ZIF-8-Melamine Foam-Functionalized Colorimetric Biosensor.

Bioaerosol infections containing pathogenic viruses and bacteria have resulted in significant economic losses and posed a serious threat to public health, as evidenced by outbreaks of coronavirus disease and avian influenza. Consequently, the sampling and screening of bioaerosols are crucial for the prevention of bioaerosol-borne diseases. In this study, an ultrasensitive biosensor based on zeolitic imidazolate framework-8-melamine foam (ZIF-8-MF) was innovatively developed for the specific capture and in situ detection of bioaerosols.

Sensitivity-enhanced hydrogel digital RT-LAMP with in situ enrichment and interfacial reaction for norovirus quantification in food and water.

Low levels of human norovirus (HuNoV) in food and environment present challenges for nucleic acid detection. This study reported an evaporation-enhanced hydrogel digital reverse transcription loop-mediated isothermal amplification (HD RT-LAMP) with interfacial enzymatic reaction for sensitive HuNoV quantification in food and water. By drying samples on a chamber array chip, HuNoV particles were enriched in situ.

A press-actuated slidable microfluidic colorimetric biosensor for Salmonella detection utilizing nickel mesh sheet and MIL-88@Pd/Pt nanoparticles.

A press-actuated slidable microfluidic colorimetric biosensor was designed for rapid, sensitive and multi-channel detection of Salmonella. The nickel mesh sheet (NMS) modified with capture antibodies was employed for capturing target bacteria, and metal organic frameworks decorated with palladium (Pd) and platinum (Pt) nanoparticles (MIL-88@Pd/Pt NPs) modified with detection antibodies were used for amplifying colorimetric signals. The capture efficiency of the immune NMS reached 83 %, and the detection limit of this colorimetric biosensor was 35 CFU/mL in 20 min.

Prohibiting the electron-phonon coupling effect in tungsten trioxide nanosheet colloid with enhanced photocatalytic antibacterial capacity.

The serious combination of abundant electrons/holes in bulk primarily hinders the efficiency in the photocatalytic reaction. It is crucial to control the spatial charge dynamics through delicately designing the crystal configuration of photocatalyst. In this work, a modified tungsten trioxide nanosheet colloid (M-WO) was synthesized by an ion exchange method.

An all-in-one microfluidic SlipChip for power-free and rapid biosensing of pathogenic bacteria.

Point-of-care testing of pathogens is becoming more and more important for the prevention and control of food poisoning. Herein, a power-free colorimetric biosensor was presented for rapid detection of using a microfluidic SlipChip for fluidic control and Au@PtPd nanocatalysts for signal amplification. All the procedures, including solution mixing, immune reaction, magnetic separation, residual washing, mimicking catalysis and colorimetric detection, were integrated on this SlipChip.

A multimetallic nanozyme enhanced colorimetric biosensor for Salmonella detection on finger-actuated microfluidic chip.

Salmonella screening is essential to avoid food poisoning. A simple, fast and sensitive colorimetric biosensor was elaborately developed for Salmonella detection on a microfluidic chip through limiting air chambers for precise air control, switching rotary valves for accurate fluid selection, a convergence-and-divergence passive micromixer and an extrusion-and-suction active micromixer for efficient fluid mixing, and immune gold@platinum palladium nanocatalysts for effective signal amplification. The mixture of bacteria, immune magnetic nanobeads and nanocatalysts was first rapidly mixed to form nanobead-bacteria-nanocatalyst conjugates and magnetically separated for enrichment.

Multiplex nanozymatic biosensing of on a finger-actuated microfluidic chip.

A colorimetric biosensor was elaboratively designed for fast, sensitive and multiplex bacterial detection on a single microfluidic chip using immune magnetic nanobeads for specific bacterial separation, immune gold@platinum palladium nanoparticles for specific bacterial labeling, a finger-actuated mixer for efficient immunoreaction and two coaxial rotatable magnetic fields for magnetic nanobead capture (outer one) and magnet-actuated valve control (inner one). First, preloaded bacteria, nanobeads and nanozymes were mixed through a finger actuator to form nanobead-bacteria-nanozyme conjugates, which were captured by the outer magnetic field. After the inner magnetic field was rotated to successively wash the conjugates and push the HO-TMB substrate for resuspending these conjugates, colorless TMB was catalyzed into blue TMB products, followed by color analysis using ImageJ software for bacterial determination.

Cost-Efficient Micro-Well Array-Based Colorimetric Antibiotic Susceptibility Testing (MacAST) for Bacteria from Culture or Community.

Rapid and cost-efficient antibiotic susceptibility testing (AST) is key to timely prescription-oriented diagnosis and precision treatment. However, current AST methods have limitations in throughput or cost effectiveness, and are impractical for microbial communities. Here, we developed a high-throughput micro-well array-based colorimetric AST (macAST) system equipped with a self-developed smartphone application that could efficiently test sixteen combinations of bacteria strains and antibiotics, achieving comparable AST results based on resazurin metabolism assay.

Magnetic nanobead chain-assisted real-time impedance monitoring using PCB interdigitated electrode for detection.

Pathogen testing is effective to prevent food poisoning. Here, an electrochemical biosensor was explored for detection by combining magnetic grid based bacterial separation with enzymatic catalysis based signal amplification on a PCB interdigitated electrode in a microfluidic chip. First, immune magnetic nanobeads, target bacteria, and immune polystyrene microspheres decorated with glucose oxidase were sufficiently mixed to form nanobead-bacteria-microsphere sandwich conjugates.

Deep learning enhanced multiplex detection of viable foodborne pathogens in digital microfluidic chip.

Culture plating is worldwide accepted as the gold standard for quantifying viable foodborne pathogens. However, it is time-consuming (1-2 days) and requires specialized laboratory and personnel. This study reported a deep learning enhanced digital microfluidic platform for multiplex detection of viable foodborne pathogens.

Computer vision-assisted smartphone microscope imaging digital immunosensor based on click chemistry-mediated microsphere counting technology for the detection of aflatoxin B in peanuts.

Aflatoxin B is a carcinogenic contaminant in food or feed, and it poses a serious health risk to humans. Herein, a computer vision-assisted smartphone microscope imaging digital (SMID) immunosensor based on the click chemistry-mediated microsphere counting technology was designed for the detection of aflatoxin B in peanuts. In this SMID immunosensor, the modified polystyrene (PS) microspheres were used as the signal probes and were recorded by a smartphone microscopic imaging system after immunoreaction and click chemistry reaction.

A Lab-on-a-Tube Biosensor Combining Recombinase-Aided Amplification and CRISPR-Cas12a with Rotated Magnetic Extraction for Detection.

Background: Foodborne pathogenic bacteria threaten worldwide public health, and simple bacterial detection methods are in urgent need. Here, we established a lab-on-a-tube biosensor for simple, rapid, sensitive, and specific detection of foodborne bacteria.

Methods: A rotatable Halbach cylinder magnet and an iron wire netting with magnetic silica beads (MSBs) were used for simple and effective extraction and purification of DNA from the target bacteria, and recombinase-aided amplification (RAA) was combined with clustered regularly interspaced short palindromic repeats/CRISPR-associated proteins12a(CRISPR-Cas12a) to amplify DNA and generate fluorescent signal.

Rapid detection of multiple antibiotics in chicken samples a fluorescence nanobiosensor coupled with a homemade fluorescence analyzer.

Antibiotic residues in foods pose a serious threat to human health. However, routine analysis techniques require bulky laboratory instruments and skilled personnel or give single-channel analysis results, exhibiting low practicality. Here, we explored a rapid and easy-to-use detection system combining a fluorescence nanobiosensor with a homemade fluorescence analyzer for the simultaneous identification and quantification of multiple antibiotics.

Semi-circle magnetophoretic separation under rotated magnetic field for colorimetric biosensing of Salmonella.

Magnetic separation was often applied to isolate and concentrate foodborne bacteria using immunomagnetic nanobeads before downstream bacterial detection. However, nanobead-bacteria conjugates (magnetic bacteria) were coexisting with excessive unbound nanobeads, limiting these nanobeads on magnetic bacteria to further act as signal probes for bacterial detection. Here, a new microfluidic magnetophoretic biosensor was elaboratively developed using a rotated high gradient magnetic field and platinum modified immunomagnetic nanobeads for continuous-flow isolation of magnetic bacteria from free nanobeads, and combined with nanozyme signal amplification for colorimetric biosensing of Salmonella.

A novel linear displacement isothermal amplification with strand displacement probes (LDIA-SD) in a pocket-size device for point-of-care testing of infectious diseases.

Nucleic acid amplification is crucial for disease diagnosis, especially lethal infectious diseases such as COVID-19. Compared with PCR, isothermal amplification methods are advantageous for point-of-care testing (POCT). However, complicated primer design limits their application in detecting some short targets or sequences with abnormal GC content.