Article

Optical Chemical Sensors

Biomedical Diagnostics Institute, Dublin City University, Glasnevin, Dublin 9, Ireland.
Chemical Reviews (Impact Factor: 46.57). 03/2008; 108(2):400-22. DOI: 10.1021/cr068102g
Source: PubMed

ABSTRACT

Optical chemical sensors (OCS) is defined as miniaturized devices that can deliver real time and on-line information on the presence of specific compounds or ions in a complex samples. The most widely used techniques utilized in OCS are optical absorption and luminescence. In yielding analyte information, the OCS employ optical transduction techniques. This review will concentrate on developments in OCS with major emphasis from 2000 to the present day. The recent developments in this field have been driven by factors such as the availability of low-cost, miniature optoelectronic light sources and detectors, the need for multianalyte array-based sensors, specifically in the area of biosensing, advances in microfluidics and imaging technology, and the sensor network, as well as optical materials and components.

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Available from: Brian D Maccraith, Jan 18, 2014
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    • "Both luminescent methods are widely used for sensing of many parameters such as pH and the concentration of CO 2 or O 2 [25]. In a similar way, colour changing dyes can also be used for sensing purposes [23,25,26]. PCS fibres, fibre tapers, fibre tips or other structures can be coated with a polymer or silica gel containing an organic indicator dye [27]. "
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    • "Some of these advantages are the availability of low-cost miniature optoelectronic light sources and detectors, the versatility of formats and materials for the development of optical sensing phases, the absence of electromagnetic interferences and the flexibility for designing multi-analyte array-based sensors or for integrating optical chemical sensors into sensor networks [8]. Currently, the most commonly techniques employed in optical chemical sensors are optical absorption and luminescence [1] [6]. In this work, we focus on luminescent chemical sensors based on the measurement of luminescence lifetime. "
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    • "Optical chemical sensors play an important part in industrial , environmental and clinical monitoring thanks to their low cost, possibility for miniaturization and great flexibility [1], [2]. Among different types of optical chemical sensors, colorimetric sensors are especially attractive because they recognize analytes through color change that allows obtaining the visually observed and easily measurable analytical signal [3], [4]. "
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