Sensors, electrochemical potentiometric

The idea of separating the gas sample by a gas-permeable membrane from the actual internal sensing element is common to several types of electrochemical and some optical sensors. The potentiometric Severinghaus electrode and the amperometric oxygen Clark electrode have already been discussed. Actually, most types of sensors can be used in this configuration and the conductometric sensor is not an exception (Bruckenstein and Symanski, 1986). 

Electrode modification by the attachment of various types of biocomponents holds considerable promise as a novel approach for electrochemical (potentiometric, conductometric, and amperometric) biosensors. Potentiometric sensors based on coupled biochemical processes have already demonstrated considerable analytical success [26,27]. More recently, amperometric biosensors have received increasing attention [27,28] partially as a result of advances made in the chemical modification of electrode surfaces. Systems based on... 

Electrochemical, potentiometric Legin (Russia) Determination of heavy metals with an array of chalcogenide membrane sensors. [15]... 

Chemical sensors may be classified according to the operating principle of the transducer. Based on this classification, electrochemical sensors are such chemical sensors where the chemical information is transduced into an electrical signal. Electrochemical sensors can be divided further into -> amperometric sensors, -> conduc-timetric sensors, and -> potentiometric sensors, depending on which electrical property is actually recorded. 

Potentiometric sensors -> Electrochemical sensors for which the - potential of the -> indicator electrode is measured against a -> reference electrode. The commonly used - pH-sensitive electrodes and -> ion-selective electrodes belong to the group of potentiometric sensors. Se also potentiometry. 

Solid-State Electrochemical Potentiometric Sensors for Gas Analysis. . . 1105 H. -H. Mdbius... 

Solid-State Electrochemical Potentiometric Sensors for Gas Analysis... 

The inner filling solution for the sensors is usually 0.01 M NaCl, which is also used to condition the potentiometric sensors. Electrochemical potential is measured with the following galvanic cell Ag/AgCl/bridge electrolyte/sam-ple solution/ion-selective membrane/inner filling solution/ AgQ/Ag. A high impedance pH-mV meter is used to measure the electrochemical potential. Selectivity coefficients are evaluated by the matched potential method (also known as method of mixed solutions), or via the separate solution method. 

Mdbius HH (1991) Solid state electrochemical potentiometric sensors for gas analysis, hi Gopel W, Hesse J, Zemel JN (eds) Sensors a comprehensive survey. VCH, New YorkAVeinheim... 

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