Biosensor thermal

Thermal biosensors have attracted less consideration. Moreover, adverse comments like complicated thermostating, very weak sensitivity or non-specific heating effects have resulted in a poor reputation. Actually, this trend is surprising because thermal biosensors have influenced the whole of biosensor research over and over again (Mosbach, 1991). Especially the enzyme thermistor (ET) has enriched our knowledge about immobilized multi-enzyme systems for signal amplification, the use of immobilized coenzymes and different immobilization techniques. Moreover, ET basic research was decisive for immunosenso-rics or concanavalin-A-based reversible biosensors. Thermal biosensors have multiple advantages ... 

Electrical conductivity measurements revealed that ionic conductivity of Ag-starch nanocomposites increased as a function of temperature (Fig.l7) which is an indication of a thermally activated conduction mechanism [40]. This behavior is attributed to increase of charge carrier (Ag+ ions) energy with rise in temperature. It is also foimd to increase with increasing concentration of Ag ion precursor (inset of Fig.l7). This potentiality can lead to development of novel biosensors for biotechnological applications such as DNA detection. 

AET has also demonstrated very high operational thermal stability for immobilized biocatalysts, which is applicable to a multitude of industrial areas including the biocat-alytic and biosensor industries. 

Qian Z, Tan TC (1999) BOD measm ement in the presence of heavy metal ions using a thermally-kiUed Bacillus subtilis biosensor. Water Res 33 2923 -2928... 

Conventional calorimetric biosensors with thermistors as the transducer were invented early by proposing a thermal biosensor in a flow stream [10]. So far the design of enzyme thermistors does not entirely match the market demand well, but it seems well suited for special applications [10,11]. A number of devices have utilized discrete pairs of thermistors for differential measurements with immobilized enzymes or with separate enzyme columns [9,10,11],... 

If silicon technology is involved all thermal sensors suffer from the high thermal conductivity of silicon, which dramatically decrease their sensitivity [12]. However, by use of micromachining and integrated silicon technology a powerful thermal biosensor can be realized. Using a thermopile integrated on a thin micromachined silicon membrane reduces thermal loss due to the substrate and so excellent performance can be accomplished [13]. 

The goal of this book is to summarize the recent advances in carbon nanotubes as a new material for electrochemical sensors. Since their discoveiy in 1991, carbon nanotubes have received considerable attention in different fields. Their speeial geometry and unique electronic, mechanical, chemical and thermal properties make them a very attractive material for the design of electrochemical biosensors. 

Recent reports indicate that divalent transition metal ions, such as Cu +, forming links between two artificial hydroxypyridone nucleobases can efficiently replace the hydrogen bonding between natural nucleobases, A-T and G-C, in oligonucleotides. Such artificial metal-mediated base pairs results in a moderate increase in the thermal stability of the duplex. They could lead to nucleic acid materials with novel chemical and physical properties. Such ohgonucleotide derivatives are of interest for the design of biosensors, nanomolecular wires, and switches. 

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