Optical chemical sensor

O. S. Wolfbeis, ed.. Fiber Optic Chemical Sensors Vol. 2, Chemical Rubber Co. Press, Boca Raton, Fla., 1991. 

Matsubara, K., Kawata, S. and Minami, S. (1988) Optical chemical sensor based on surface plasmon measurement Appl. Opt., 27, 1160-1163. 

F. Baldini et al. (eds.), Optical Chemical Sensors, 1-15. 2006 Springer. Printed in the Netherlands. 

FIBER OPTIC CHEMICAL SENSORS AND BIOSENSORS A VIEW BACK... 

Other very early work includes that of Boisde at the CEA9,10. A scheme of the experimental set-up used by his group is given in Fig. 1. The fiber optic pH sensor described by Peterson et al.11 in 1980 was another milestone. A 2-volume book that appeared in 1991 gives an account of the early work on fiber optic chemical sensors and biosensors12 up to about 1989. Earlier reviews include those of Kirkbright et al.13, Borman14, and Hirschfeld et al.15. 

Figure 3. First fiber optic chemical sensor (from ref. [17] used for sensing oxygen). Alos shown is a cross-sedction of the fiber bundle used. 6 light source 9 photodectectors 16 chemically sensitive layer.

This section covers early indirect fiber optic chemical sensors (FOCS) for species that cannot be sensed directly but require the use of indicators, probes, labeled biomolecules, or color-forming reactions. 

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... 

Fig. 5 shows the instrumental arrangement of the commercially most successful optical chemical sensor between 1984 and 2000. It is used in about 70% of all critical care operations in the US to monitor pH, pC02 and p02 in the cardiopulmonary bypass operations35. It contains 3 fluorescent spots, each sensitive for one parameter, in contact with blood. Fluorescence intensity is measured at two wavelengths and the signals are then submitted to internal referencing and data processing. 

Table 4. Selection of Commercial Fiber Optic Chemical Sensors.

Miller H.H., Hirschfeld T.B., Fiber optic chemical sensors for industrial and process control, Proc. SPIE-Int. Soc. Opt. Eng. 1987 718 39. 

Edmonds T.E., Ross I.D., Low-cost fiber optic chemical sensors, Anal. Proceed. 1985 22 206. 

The signal conversion, occurring in the fibre optic chemical sensors (FOCS), proceeds in several steps, which are shown in Figure 1. 

Figure 1. Signal conversion in fibre optic chemical sensor. 47...

An integral part of a fibre optic sensor is the light source. Its primary task is to deliver an appropriate light, which possesses such features as an optical power suitable to interact with an analyte or an indicator from the optrode, a wavelength matched to the spectral properties of the sensors in order to obtain the highest sensitivity, and, in dependence on the construction of the sensor, polarisation, short pulse etc. There are many various light sources utilised in the fibre optic chemical sensors. They differ in spectral properties, generated optical power and coherence. 

Successful development of fibre optic chemical sensors requires the cooperation of many specialists in various fields of science. Scientists in analytical chemistry, polymer science, material science, optoelectronics and electronics etc. can be involved in this multidisciplinary task. Depending on the application of the sensor biologists, medical doctors or environmentalists can also be incorporated to the working group. Although, the contribution of all specialists cannot be classified by the importance, analytical chemistry and material science seem to be the key to the success. 

Wolfbeis O.S., Fibre optic chemical sensors and biosensors, Vol. 1 and 2. Boca Raton FL CRC, 1991. 

Fiber-optic chemical sensors (FOCSs) represent a subclass of chemical sensors in which an optical fiber is used as part of the transduction element. 

A new Ni(II) optical chemical sensor based on immobilizing of 2-amino-lcyclopentene-ldithiocarboxylic acid (ACDA) (Figure 21), to transparent acetyl cellulose films was developed52. 

The interdisciplinary nature of optical chemical sensors opens a variety of new directions in sensor development. The issue of chemical selectivity is... 

Arnold M.A., Fiber-optic chemical sensors, Anal. Chem. 1992 64 1015A-1025A. 

Seitz W.R., Optical ion sensing, in Fiber optic chemical sensors and biosensors II (Wolfbeis O.S., ed.), CRC Press, Boca Raton, Florida, 1991. 

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