Interdigitated array electrode system

Interdigitated microband arrays (IDAs) are another example of an electrode system with spatially variant electrode kinetics. The sj tem consists of two... 

Figure 2.7. The electrochemical detection system for 0X5d eracycline [OTC] using aptamer-immoblllzed interdigitated array (IDA) gold electrode chip. Left An IDA gold electrode chip and the IDA gold electrode. Right A typical electrochemical reaction occurring after aptamer binds to its target...

There are two types of OTEs [384], A metal microgrid with small (10-30-[xm) holes, which allows >50% of the radiation to be transmitted, or an interdigitized array metal electrode [385] may be used for identification of products or intermediates in redox systems [386, 387], The other type is comprised of a metal film deposited on a transparent support. The thickness of this film is a compromise between its electrical conductivity and optical transparency. This type of OTE can be used for surface analysis, particularly when the metal of the working electrode can provide the surface enhancement (Section 3.9.4). 

Figure 7. Diagram showing an experimental system used for DEP or twDEP. The interdigitated electrode array is fabricated on a glass substrate and energized with different AC signals. For DEP, the electrodes are connected to voltages with 180° phase shifts. For twDEP, the electrodes are connected to a frequency generator with 90° phase shift, w is the electrode width, g is the electrode gap and h is the height of the channel.

Dielectrophoresis, Fig. 6 (a) Schematic diagram of the interdigitated electrode array in a microfluidic system, (b) Plot of the direction of the dielectrophoretic force for the... 

Impedimetric measurements are inherently nonselective, but the modification of electrode surfaces with selective recognition agents has resulted in selective sensing devices based on impedimetric transducers. Reviews of immunosensors and cell-based biosensors include sections on impedance transduction [177, 250, and references therein]. A review of bioelec-tronic noses, devices intended to mimic the human olfactory system in detecting and identifying odors, includes interdigital structures for complex impedance measurements and arrays of capacitive sensor elements [251]. 

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