E-Tongue (TOP2-285)
Nanosensor Array for Detection of the Presence of One or More Specified Chemical Components in a Liquid
NASA Ames has expanded the nano chemical sensor technology from the E-nose to E-tongue. E-Tongue, a patent-pending technology, is comprised of silicon-based interdigitated electrode (IDE) array with nanostructured materials that can detect biomolecules and chemical compounds in a liquid sample. The technology adopts a novel approach where analytes are not detected using highly-specific target receptor, but rather it utilizes an array of low-specificity sensors that yield electrical signals that act as signatures specific to the molecules present. The technology provides a sensing platform for liquid samples to detect the presence of target components. This invention not only takes relatively little time for detection, is quantitatively specific for identifying the presence of one or more target components of a liquid, but also uses a minimum number of chemical or physical tests that can be performed simultaneously or sequentially.

The Technology
Interested chemicals and biological species, such as amino acids, DNA, minerals, salts and dissolved organic volatiles in water, may be found in liquids but some of them potentially are undetectable in gas. Thus, it may be useful to test certain bodily fluids for the presence of one or more target components, such as troponin or glucose, which may also not be as efficiently detectable in gas or liquid when utilizing existing technologies available in the market. Such target components may be of significance due to their association with the presence of life or due to their correlation with a specific health and environmental condition. The E-Tongue technology, a silicon-based interdigitated electrode array-sensing platform, is comprised of a variety of nanostructure materials, which undergo a change in electrical properties - such as resistance or current - when biomolecules become bound to them. The measured electrical signal is processed through signal processing algorithms to provide interpretable results. As an example, E-Tongue has been used for liquid amino acid detection, in which the sensing materials are unmodified or carboxylic-acid-group-modified carbon nanotubes (though not exclusively limited to these two). These sensing materials can be expanded to use other materials as well, as long as they are able to detect and provide sensitivity to the amino acid target component. Two amino acids, Glycine and Lysine, have been used as target molecules for detection, with sodium chloride solution acting as the reference sample. Other target components, such as the previously mentioned chemicals and biological samples and more, can be detected based on the sensing materials' selectivity. The E-Tongue technology, a compact tool for target component detection, has an inherent advantage as it utilizes and expands the matured E-Nose technology platform and electronics.
A silicon-based 32-sensor array chip with unique coatings of sensing materials whose data is converted into a unique response pattern - "Taste Print" or "Taste signature" - for component identification and concentration prediction using pattern recognition and linear regression algorithms.
  • Adaptable to a wide range of analytes
  • Capable of detecting mixtures of analytes
  • Saves time, in-situ real time detection
  • Low-cost, compact, and low power consumption
  • Non-invasive
  • Adopts an Internet-of-things (IoT) approach in data processing and presentation through the integration with smartphones
  • Effective portable solution
  • Concentration of the amino acid detection in the range of ppm to percentage

  • Biomedical research
  • Clinical applications (e.g., biomolecule and biomarker detection for blood testing, glucose measurement, disease detection, etc.)
  • Pollutant detection in water treatment, food and beverage quality assurance
  • Soil analysis and quality assurance for agriculture, marine water quality monitoring
  • Detection of chemical or biological weapons
  • Pharmaceutical industry
Technology Details

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