The basic features and most salient examples of flow-through chemical and biochemical sensors based on the integration of derivative analytical reactions, separation processes (dialysis, gas diffusion, sorption, liquid-liquid extraction) and detection (optical, electroanalytical, mass, thermal) are presented and discussed, and critically compared with those of probe-type sensors and conventiona...

Thin films of analyte-specific hydrogels were combined with microfabricated piezoresistive pressure transducers to obtain chemomechanical sensors that can serve as selective biochemical sensors for a continuous monitoring of metabolites. The gel swelling pressure has been monitored in simulated physiological solutions by means of the output signal of piezoresistive sensors. The interference by ...

Conducting organic polymers have found two main kinds of application in electronics so far: as materials for construction of various devices and as selective layers in chemical sensors. In either case, interaction with ambient gases is critical. It may compromise the performance of a device based on conducting polymers, whereas it is beneficial in a sensor. Conductivity has been the primary pro...

Chemical sensors based on individual single-walled carbon nanotubes (SWNTs) are demonstrated. Upon exposure to gaseous molecules such as NO(2) or NH(3), the electrical resistance of a semiconducting SWNT is found to dramatically increase or decrease. This serves as the basis for nanotube molecular sensors. The nanotube sensors exhibit a fast response and a substantially higher sensitivity than ...

Semiconducting nanoparticle tin oxide-based sensors have been prepared with a pressure load of 4, 6, 8, 10 tons and reinforced with carbon nanofibers (CNF) in SnO2 matrix. The SnO2/CNF sensor’s sensitivity for ethyl alcohol has increased by a factor of two, in compared with that of pure SnO2 8-ton pressed sensor with lower response time. These results open the way towards further optimized lowe...

Chemical sensors have been widely used for the analysis of volatile organic compounds. Employing chemical sensors in an array format with pattern recognition provides a higher degree of selectivity and reversibility leading to an extensive range of applications. When such systems are used for odour analysis they are termed ‘electronic noses’. Application of electronic noses ranges from the food...

1. INTRODUCTION Among the classes of highly porous materials, metalÀorganic frameworks (MOFs) are unparalleled in their degree of tunability and structural diversity as well as their range of chemical and physical properties. MOFs are extended crystalline structures wherein metal cations or clusters of cations (" nodes ") are connected by multitopic organic " strut " or " linker " ions or molec...

The rapidly increasing use of sensors throughout different research disciplines and the demand for more efficient devices with less power consumption depends critically on the emergence of new sensor materials and novel sensor concepts. Atomically thin transition metal dichalcogenides have a huge potential for sensor development within a wide range of applications. Their optimal surface-to-volu...