Fluorescent Sensing and Process Analytical Applications

Preclinical Development, GlaxoSmithKline, Research Triangle Park, NC, USA 

Luminescence, in particular photoluminescence, constitutes a well-established discipline in analytical science where the cited hallmarks include remarkable sensitivity, wide dynamic range and low detection limits (-10under suitable conditions). These collective merits are often umivaled by other optical techniques, and hence its wide adoption in the life sciences for determining trace constituents in biological and environmental samples. Moreover, its fast response, high spatial resolution and remote sensing capabilities make it attractive for real-time analytical problems such as process manufacturing (process analysis or PAT) and field applications.  

The purpose of this chapter is to provide an overview of luminescence techniques for real-time monitoring. This review provides (i) an introduction to luminescence fundamentals (ii) an outline of various luminescence techniques, with particular focus on steady state photoluminescent sensing (iii) an overview of the emission measurement risks and (iv) a discussion of current and potential PAT applications. 

Process Analytical Technology 2e Edited by Katherine Bakeev 2010 John Wiley Sons, Ltd. 

Luminescence is a well-established class of analytical spectroscopic techniques where a species emits light after excitation. Emission is an elecnonic nansition from an excited state as opposed to the ground state as is the case in most other spectroscopies. Photoluminescence, or light-induced fluorescence (LIE), is the most common route to induce emission where sufficient incident photons of a particular energy excite the target species via absorption. Although less common, nomadiative excitation can also occur via a chemical reaction termed chemiluminescence. Unless otherwise stated, the terms luminescence and fluorescence within this review infers excitation by light induction. 

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