Durable sensor

Lugtenberg, Ronny J.W., Selective Ion Recognition with Durable Sensors,... 

In our group the TMS model was upgraded by including divalent cations and ion-pair association in the system [22] and by the introduction of free and immobilized electroactive components in the membrane (i.e. receptor molecules and anionic sites) [21,29]. The effect of immobilization is of special importance for the sensor design, because covalent attachment of the electroactive components to the membrane seems to be an attractive possibility to obtain durable sensors. 

Selective Ion Recognition with Durable Sensors (Lugtenberg and Reinhoudf) Self-Assembling Systems on Scales from Nanometers to Millimeters Design and Discovery (Issues, Chin, Bowden, Xia and Whitesides)... 

Choice of sensors and probes. The choice of the sensors should take into account their stabihty as a function of time, so that the necessary calibrations and maintenance can be planned. Initial sensor calibration has to be documented. For remote or inaccessible locations only very robust and durable sensors should be installed. 

Implementation of durable sensors in total analysis systems... 

Adsorption is the simplest way to fix bioactive molecules at an electrode surface. Commonly, adsorbed molecules are bound by weak forces, resulting in less durable sensors. Adsorption is useful to immobihze enzymes, antibodies and nucleic acids. 

Lugtenberg, Ronny J.W., Selective Ion Recognition with Durable Sensors, 4, 193. Luisi, Pier Luigi, Why Giant Vesicles , 6, 3 ... 

There is no doubt that metallic nanoparticles that have defined sizes and shapes will become key components of a number of novel, highly sophisticated products, the prototypes of which are currently emerging from the industrial R D departments. The outlook is promising for the industrial production of defined 1.4nm metal clusters for use as single electron switches or transistors, for the cost-effective fabrication of ultrapure metallic nanomaterials needed for dye solar cells or sensors, and for the reproducible production of (particularly) efficient and durable... 

The highly dispersible calix[4]arene neutral carriers can also improve the durability for neutral-carrier-type ion sensors. Time-course changes in both sensitivity (slope for Na+ calibration graph) and selectivity (selectivity coefficient for Na" " with respect to K+) were followed in the Na -ISFETs based on ion-sensing membranes of silicone rubber-(l), plasticized PVC-(l), and plasticized PVC-(2) (Fig. 2). Deterioration proceeded quite quickly in the Na -ISFETs of plasticized PVC-(2) both the Na+ sensitivity and selectivity... 

Appropriate fabrication of sol-gel-derived membranes encapsulating neutral carriers such as valinomycin can afford an excellent type of neutral-carrier-type ion-sensing membranes for ISFETs [27] as already mentioned. The simple encapsulation of neutral carriers in sol-gel-derived membranes, however, has a drawback the encapsulated neutral carriers are still apt to exude from the membranes into aqueous sample solutions, which thereby makes the resulting ion sensors less durable and more toxic. Incorporation of neutral carriers to sol-gel-derived membranes by covalent bonding is desirable. 

So the function of special optical fibres for sensing is to produce a sensitive response to changes in the fibre surroundings. Such requirements on optical hardware as durability to the analyte, transparency (i.e. minimum optical losses) in a wide spectral range and common availability should be pointed out. Related to the these requirements, the choice of the fibre material as well as of the fibre coating and fibre structure belong to fundamental tasks in the design of fibre-optic sensors. 

Durability of Sensor Properties With Respect to the Sensor Application... 

It is known from laboratory tests that surface tension measurement can provide reliable information regarding existing detergent concentration. Work is being carried out in various institutes on such sensors for the commercial sector. However, for use in domestic washing machines, only sensors that are extremely inexpensive, maintenance-free and durable are suitable. How much of a breakthrough can be achieved here in the future remains to be seen. 

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