Sensing optical

Costa-Fernandez, J. M. Pereiro, R. and Sanz-Medel, A. (2006). The use of luminescent quantum dots for optical sensing. Trends in Anal. Chem., 25,207-218. 

Murphy, C. J. (2002). Optical Sensing with Quantum Dots. Anal Chem., 74, 520A-526A. 

While several optical chemical sensors and biosensors in use that do not rely on fiber optics, the commercialization of FOCS technology started slowly, probably because of the limitations imparted to optical sensing if... 

Wang E., Meyerhoff M.E., Anion selective optical sensing with metalloporphyrin-doped polymeric films, Anal. Chim. Acta 1993, 283 673. 

Schwotzer G. et. al., Optical sensing of hydrocarbons in air or in water using UV absorption in the evanescent field of fibers, Sensors Actuators B 1997 38 150-153. 

Optical sensors rely on optical detection of a chemical species. Two basic operation principles are known for optically sensing chemical species intrinsic optical property of the analyte is utilized for its detection indicator lor label) based sensing is used when the analyte has no intrinsic optical property. For example, pH is measured optically by immobilizing a pH indicator on a solid support and observing changes in the absorption or fluorescence of the indicator as the pH of the sample varies with time1 20. 

Mohr G., Materials and Polymers in Optical sensing, ASCOS 2000, Workshop on Optical chemical Sensors Biosensors, 2000. 

The versatility of luminescence goes beyond intensity-, wavelength- and kinetic-based measurements. Fluorescence polarization (or anisotropy) is an additional parameter still largely unexplored for optical sensing yet widely used in Biochemistry to study the interaction of proteins, the microfluidity of cell membranes and in fluorescence immunoassays. Although only a few optosensors based on luminescence polarization measurements can be found in the literature, elegant devices have recently been reported to measure chemical parameters such as pFI or O2 even with the bare eye41. 

McDonagh C., MacCraith B.D., McEvoy A.K., Tailoring of Sol-Gel Films for Optical Sensing of Oxygen in Gas and Aqueous Phase, Anal. Chem. 1998 70 45-50. 

The mid-IR range is attractive for optical sensing as highly molecule-specific information is provided, but difficult to access with standard sensor instrumentation. The application of mid-IR sensors is in particular of interest... 

Figure 3. A typical configuration for absorption-based optical sensing.

Vast majority of the optical sensing systems are of the modulation type and its functional structure can be sketched as in Figure 1. 

Many integrated optical sensing systems have been designed, realized and tested in the laboratories but only a few of them have reached the market. 

Many classical optical sensing principles, which are well known from free space optics can be implemented in integrated optical structures, while integrated optics at its turn can act as source of new principles. Many types of integrated optical sensors have been investigated and demonstrators have been realized, mostly at universities and other research institutes. And also at... 

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