Science Daily November 25, 2020 Researchers in the UK investigated fluorescent nanodiamonds as an ultrasensitive label for in vitro diagnostics, using a microwave field to modulate emission intensity and frequency-domain analysis to separate the signal from background autofluorescence, which typically limits sensitivity. Focusing on the widely used, low-cost lateral flow format as an exemplar, they achieved a detection limit of 8.2 × 10−19 molar for a biotin–avidin model, 105 times more sensitive than that obtained using gold nanoparticles. Single-copy detection of HIV-1 RNA can be achieved with the addition of a 10-minute isothermal amplification step. This ultrasensitive quantum diagnostics platform […]
Tag Archives: Biotechnology
Detecting bacteria with fluorescent nanosensors
Nanowerk November 25, 2020 Researchers in Germany developed a set of near infrared fluorescent nanosensors are based on single-walled carbon nanotubes that fluoresce in the NIR optical tissue transparency window which offers ultra-low background and high tissue penetration. They are chemically tailored to detect released metabolites as well as specific virulence factors and integrated into functional hydrogel arrays with 9 different sensors. These hydrogels are exposed to clinical isolates of 6 important bacteria and remote (≥25 cm) NIR imaging allows to identify and distinguish bacteria. Sensors are also spectrally encoded to differentiate the two major pathogens P. aeruginosa as well as […]
Grabbing Viruses Out of Thin Air
Asia Research News November 25, 2020 An international team of researchers (Japan, China, UK) review the state of the art of research on biosensor materials for virus detection. Topics covered include a general description of the principles for virus detection, a critique of the experimental work dedicated to various virus sensors, a summary of their detection limitations. They examined the piezoelectric sensors used for the detection of human papilloma, vaccinia, dengue, Ebola, influenza A, human immunodeficiency, and hepatitis B viruses. Magnetostrictive sensors for the detection of bacterial spores, proteins, and classical swine fever are covered. Progress related to early detection […]
Novel magnetic spray transforms objects into millirobots for biomedical applications (with video)
EurekAlert November 18, 2020 An international team of researchers (Hong Kong, China) has constructed millirobots by coating inanimate objects with a composited agglutinate magnetic spray. The technique enables a variety of 1D, 2D, or 3D objects to be covered with a thin magnetically drivable film (~100 to 250 micrometers in thickness). The film is thin enough to preserve the original size, morphology, and structure of the objects while providing actuation of up to hundreds of times its own weight. Under the actuation of a magnetic field, the millirobots are able to demonstrate a range of locomotive abilities: crawling, walking, and […]
Chemists create new crystal form of insecticide, boosting its ability to fight mosquitoes and malaria
Phys.org October 12, 2020 A team of researchers in the US (New York University, University of Puerto Rico) heated the commercially available form of deltamethrin to 110°C/230°F for a few minutes and let it cool to room temperature; this resulted in a new crystallized form of deltamethrin, composed of long, tiny fibers radiating from a single point. When mosquitoes step on insecticide crystals, the insecticide is absorbed through their feet and, if effective, kills the mosquitoes. In tests the new form was up to 12 times more effective against mosquitoes than the existing form. The new form also remained stable—and […]
‘Like a fishing net,’ nanonet collapses to trap drug molecules
Science Daily October 5, 2020 Natural biomolecules such as peptides and DNA can dynamically self-organize into diverse hierarchical structures. Researchers at the Northwestern University have reported both experiments and simulations on the dynamic network self-assembly and subsequent collapse of the synthetic homopolymer poly(propylene sulfone). The assembly is directed by dynamic noncovalent sulfone–sulfone bonds that are susceptible to solvent polarity. The hydration history controls the homopolymer assembly into uniform nanostructured hydrogels of spherical, vesicular, or cylindrical morphologies. The electrostatic hydrogels achieve >95% encapsulation efficiency for hydrophilic small molecules and biologics. This system validates sulfone–sulfone bonding for dynamic self-assembly, presenting a robust […]
A step toward a universal flu vaccine
MIT News October 7, 2020 Most flu vaccines consist of inactivated flu viruses coated with a protein called hemagglutinin (HA), which helps them bind to host cells. After vaccination, the immune system generates squadrons of antibodies which almost always bind to the head of the HA protein which mutates rapidly. Parts of the HA stem very rarely mutate. The immune system is intrinsically not good at seeing the conserved parts of these proteins, which if effectively targeted would elicit an antibody response that would neutralize multiple influenza types. A team of researchers in the US (MIT, Harvard University, industry) describe […]
Color-coded biosensor illuminates in real time how viruses attack hosts
Science Daily September 25, 2020 Researchers at the Colorado State University invented a biosensor that lights up blue when viral translation is happening, and green when normal host translation is happening, in single living cells. They have shown this host-attacking process, at the single-molecule level in living cells, and they have reproduced these behaviors in computational models. The models showed that both healthy human RNA and viral RNA fluctuate between states that actively express proteins and those that are silent. The combination of their sensors and computational analyses provide powerful tools to understand, predict, and control how future drugs might […]
Scientists Have Found a Molecule That Allows Bacteria to ‘Exhale’ Electricity
Science Alert September 27, 2020 At any given time, billions of the bacteria are buzzing with electricity beneath the seafloor. Using advanced microscopy techniques a team of researchers in the US (Yale University, Pacific Northwest National Laboratory) found that, stimulated by the electric field, the microbes assemble into dense biofilms, interlinked piles of hundreds of individual microbes, moving electrons through a single shared network. They found the “unique fingerprint” of each amino acid in the proteins that make up Geobacter’s signature nanowires. And when stimulated by an electric field, Geobacter produce a previously unknown kind of nanowire made of a […]
Insect wings inspire new ways to fight superbugs
EurekAlert August 18, 2020 New anti-bacterial surfaces are being developed, featuring different nanopatterns that mimic the deadly action of cicadas and dragonflies’ wings. In a review article an international team of researchers (Australia, Spain, USA – Ohio State University, UK) has detailed exactly how these patterns destroy bacteria – stretching, slicing, or tearing them apart. They point out that different species have wings that are better at killing some bacteria than others, the wing surfaces have different density, height, and diameter of the nanopillars. The nanostructured surfaces could be used in medical or industrial applications…read more. TECHNICAL ARTICLE