Novel "eNOSE" sensors for environmental applications
No Thumbnail Available
Authors
Guerbaz, Mustapha
Issue Date
2006
Type
Thesis
Language
en
Keywords
Environmental engineering
Alternative Title
Abstract
An electronic nose (eNose) is an analytic device used for detecting vapor chemicals. It functions using an array of broadly tuned chemical sensors that interact with broad range of chemicals with varying strengths. Consequently, an incoming analyte stimulates many of the sensors in the array, and elicits a characteristic response pattern, which is further analyzed for the benefit of the specific application.
The basic construction of an eNose is made of five major blocks including the following: 1) Odor or odorant 2) Sampler 3) Sensor array 4) Acquisition 5) Pattern recognition
There are different types of eNose sensors including; Metal Oxide Gas Sensors, Conducting Polymer Gas Sensors, Acoustic Wave Gas Sensors, Field Effect Gas Sensors, Electrochemical Gas Sensors, Pellistors, Fiber-Optic Gas Sensors, Immunosensors and others. Each one of these sensors has a principle of detecting chemical contaminants. Some are for universal use, others have a determination for specific contaminants.
The eNose sensors have different applications including but not limited to; homeland security by detecting biological, chemical, and nuclear warfare agents, quality control in the food and cosmetic industry, detection of hazardous gases in plants and environmental clean-up sites, aerospace industry by monitoring the space shuttle for the safety of astronauts, and medical diagnostic of diseases making the process of detection and determination of microbial causing diseases and cancer, significantly faster than the routine methods such as ELISA, PCR and microbiological testing.
Many detection specific electronic noses are still under development, which explains the limitations to their full potential use such as loss of sensitivity in the presence of water vapor or high concentration of a single component, the requirement to an often calibration, and relatively short life of some of them. However, the eNose sensors have a high sensitivity and selectivity, which make them promising devices for diverse usage.