Polymer Films in Sensor Applications

Most polymer membrane ISEs are prepared by dissolving an ionophore in a polyvinylchloride (PVC) membrane. A large variety of plasticisers are used to increase the dielectric constant of the PVC and improve its hydrophilicity. Some membranes have complexes of the ions to be sensed to increase membrane conductivity, such as potassium tetraphenylborate in K -selective membranes. There is an extensive literature on the arcane arts of polymer membranes for electrodes with dissolved ionophores and a good review of this is given by Professor Ronald Armstrong in Section 3.7 of Gabor Harsanyi s book. Polymer films in sensor applications [14]. 

G. Harsanyi, Polymer films in sensor applications, Technomic Publishing Company, Inc., Lancaster (1995). 

G. Harsanyi, Polymer Films in Sensor Applications, Technomic, Switzerland, 1995. 

Harsanyi G (2000) Polymer films in sensor applications a review of present uses and future possibilities. Sens Rev 20(2) 98-105... 

In this electronic age, it is mandatory to use solid polymer electrolytes for different applications in science and technology. Polymer electrolytes can be shaped in the form of thin film, thereby reducing the internal resistance leading to application as gas sensing material. Few reports appeared on proton-conducting polymer films and their application to gas sensors [65]. 

In sensor applications, greater care should be taken in the selection and application of polymer films to minimize modulus effects. The effect of elastic properties of the coating materials must be taken Into consideration in the interpretation of SAW sensor data. Alternatively, the sensor community ml t take advantage of the SAW sensitivity to elastic properties to devise more sensitive sensors, and to expand the applications of these sensors. 

The effects of chemical structure on polymer film properties and applications were reviewed. The uses of conductive polymers in the bioanalytical sciences and in biosensor applications were investigated. Synthesis, characterization, and applications of CPs were reported, and the main aspects of CPs in chemical sensors and biosensors were covered. The advantages and limitations of conductive polymers for different biomedical applications like tissue engineering, biosensors, drug delivery, and bioactuators were reported. Different preparation methods for conductive polymers and the use of conductive pol5miers for electromagnetic interference (EMI) shielding applications were reviewed. ... 

Besides these rather well-documented applications, new fields have recently been explored for hb polymers. The special features of the dendritic structure on the nanometer scale, with the option of a specific confinement of functional units, the formation of cavities, and an interesting molecular dynamics, play significant roles for apphcations, for example, as thin films in sensorics and diagnostics, as porogens for nanofoams, or as carriers for additives, catalytic species, or... 

Microhotplates, however, are not only used for metal-oxide-based gas sensor applications. In all cases, in which elevated temperatures are required, or thermal decoupling from the bulk substrate is necessary, microhotplate-like structures can be used with various materials and detector configurations [25]. Examples include polymer-based capacitive sensors [26], pellistors [27-29], GasFETs [30,31], sensors based on changes in thermal conductivity [32], or devices that rely on metal films [33,34]. Only microhotplates for chemoresistive metal-oxide materials will be further detailed here. The relevant design considerations will be addressed. 

R.E. DESSY, L. BURGESS, L. ARNEY and J. PETERSEN "Fiber-optic- and polymer film-based enthalpimeters for biosensor applications" in "Chemical Sensor and Microinstrumentation", ACS Symposium series 403, 1989. 

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