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Nanotechnology Spotlight

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Showing Spotlights 57 - 64 of 122 in category Sensors, Sensing Applications (newest first):

 

Quantum dot biosensors for ultrasensitive multiplexed diagnostics

quantum_dot_biosensorIn many diagnostic processes, the detection of several protein markers is required. Rather than performing several sequential analysis steps, a multiplexed approach allows the simultaneous measurement of multiple biomarkers from the same blood sample. The convergence of nanotechnology, microtechnology, microfluidics, photonics, signal processing, and proteomics allows for the development of increasingly sophisticated and effective multiplexed point-of-care diagnostic devices. The detection of protein biomarkers can done with an optical multiplexing approach that uses dye particles of different colors. In contrast to conventional fluorescence dyes, quantum dots generate a much more powerful fluorescent signal which provides a large increase in sensitivity compared to other methods. Quantum dots are also available in multiple colors, allowing the investigators to tag each antibody with a uniquely colored quantum dot. Researchers have now demonstrated a novel and fast quantum dot-based FRET technique that is suitable for multiplexed ultrasensitive detection.

Posted: Feb 17th, 2010

Unique nanomechanical response of DNA allows high-speed direct digital detection

dna_detectionMuch of today's genetic research and diagnostics uses tools and technologies enabled by DNA's ability to bind to its complementary strand in a sequence specific manner. For biologists studying molecular mechanisms inside cells, this information helps to quantify the expression levels of genes. Detection of the binding - or hybridization - of DNA strands is at the heart of modern medicine. The technology for detecting DNA hybridization mainly relies on the use of fluorescent labels. The complementary strand coming from the sample bears a label, so detection of florescence signal indicates hybridization. While this may sound straightforward, it has major limitations. Researchers have now reported a new technique for genetic analysis using nanomechanical response of hybridized DNA/RNA molecules. This new technique is several orders of magnitude more sensitive than other approaches and it is a lot simpler to use.

Posted: Dec 21st, 2009

Simple nanotechnology paper sensor for detecting toxins in water

drinking_waterSafe drinking water has been and increasingly will be a pressing issue for communities around the world. In developed countries it is about keeping water supplies safe while in the rest of the world it is about making it safe. The potential impact areas for nanotechnology in water applications are divided into three categories - treatment and remediation, sensing and detection, and pollution prevention. Within the category of sensing and detection, of particular interest is the development of new and enhanced sensors to detect biological and chemical contaminants at very low concentration levels. Testing of water against a spectrum of pathogens can potentially reduce the likelihood of many diseases from cancer to viral infections.

Posted: Dec 8th, 2009

Counting single molecules inside nanodroplets

nanodropletsA lot of the scientific knowledge in chemistry and biology comes from experiments on ensembles of molecules by which a vast number of duplicate behaviors are investigated and averaged responses are recorded. Especially the ability to make measurements at the single molecule level provides crucial information about biological and chemical systems. This research depends on molecular manipulation technologies that are able to isolate individual molecules and sequentially transport them for measurement and, potentially, manipulation. To this end, generation and manipulation of small, highly monodisperse droplets have received a lot of attention in the biotech community recently. Using a simple droplet generator chip, scientists can generate millions of droplets in a short amount of time. Each individual droplet is isolated from another droplet, hence, meaning that a million droplets constitute a million individual microreactors running a million reactions simultaneously.

Posted: Nov 25th, 2009

Traffic monitoring with a self-sensing concrete nanotechnology road surface

asphalt"Researchers have developed a self-sensing nanotechnology composite material for traffic monitoring by using piezoresistive multi-walled carbon nanotubes as an admixture. In experiments, they studied the response of the piezoresistive properties of this composite to compressive stress and they investigated with vehicular loading experiments the feasibility of using self-sensing CNT/cement composite for traffic monitoring. This nanocomposite cement has great potential for traffic monitoring use such as in vehicle detection, weigh-in-motion measurement and vehicle speed detection. An interesting aspect of this work is that, from the eventual traffic application's point of view, the pavement itself would become the traffic detection, thus eliminating the need for separate traffic flow detection sensors.

Posted: Oct 9th, 2009

Nanotechnology sensor detects living bacteria at ultralow concentrations

nanobiosensor"In their effort to develop a fast, sensitive, selective, inexpensive, and easy-to-use method for detecting and quantifying pathogenic bacterial cells, researchers in Spain have now demonstrated a carbon nanotube based potentiometric biosensor for selectively detecting one single colony-forming unit of the bacterium Salmonella Typhi in close to real time. The most important strength of this biosensor is that simple positive/negative tests can be carried out in real zero-tolerance conditions and without cross reaction with other types of bacteria. The ease with which measurements are taken in potentiometric analysis opens the door to greater simplicity in microbiological analysis.

Posted: Oct 5th, 2009

Nanotechnology sensor can 'smell' lung cancer in exhaled breath

breath_analysisAccording to the World Health Organization, lung cancer is the leading cancer-related cause of death, accounting for 18 percent of cancer deaths and killing about 1.3 million people worldwide every year. Conventional diagnostic methods for lung cancer occasionally miss tumors and they are costly and unsuitable for widespread screening. Breath testing is a fast, non-invasive diagnostic method that links specific volatile organic compounds (VOCs) in exhaled breath to medical conditions. However, these techniques - gas chromatography/mass spectrometry, ion flow tube mass spectrometry, laser absorption spectrometry, infrared spectroscopy, polymer-coated surface acoustic wave sensors and coated quartz crystal microbalance sensors - are expensive, slow, and require complex instruments. A multidisciplinary research team at Technion - Israel Institute of Technology have now demonstrated a highly sensitive, stable, relatively inexpensive, and fast-response nine-sensor array that consists of gold nanoparticles functionalized with different organic groups that respond to various VOCs that are relevant to lung cancer.

Posted: Aug 31st, 2009

Bio-interface nanosensor visually reports damage to a material

FRET_nanosensorThe term bio-interface describes the boundary between synthetic materials such as plastics, and biological systems. This rapidly growing research area, where biology and material sciences overlap, is creating new opportunities for the design, synthesis, and optimization of biologically-enabled and biologically-inspired materials. It involves manufacturing and characterization of functional surfaces for specific interactions with bio-systems and studies of the molecular and kinetic processes occurring at such interfaces, ranging from small molecule and biomolecular interactions, to cell adhesion, differentiation and tissue formation at the interface. For example, the incorporation of proteins into polymers can result in hybrid materials that combine the properties of the polymer as a cost-effective and easy to process material with the highly evolved biological functionality of the protein, enabling new concepts for construction of sensors and biomedical materials. While researchers so far have been focusing on altering the properties of a polymer by adding the functionality of a biomolecule, a group in California has now demonstrated the reverse situation, where changes in the polymer can alter the properties of the protein.

Posted: Aug 11th, 2009