Biosensors tissue-based

Biocomponent or affinity ligand enzyme electrode, whole cell biosensor, tissue-based electrode, bacterial electrode, yeast probe, imunoelectrode, affinity electrode, receptrode, DNA-probe... 

Tissue-Based Biosensors (Oregon State University, Stanford University)... 

Whole cell and tissue-based pesticide biosensors... 

WHOLE CELL AND TISSUE-BASED PESTICIDE BIOSENSORS... 

Several examples of tissue-based amperometric biosensors are given below. 

Tables 17.1, 17.2 and 17.4 give a list of some vegetable tissue based and crude extract electrodes that have been prepared for analysis of several substrates in environmental, food and pharmaceutical samples. These tables also present the sample matrix, the tissue or crude extract used, the sensor, the range of determinable concentration, the LD, the response time and the stability and/or lifetime of the biosensor.

The tissue-based amperometric electrodes for the determination of catechol [13,14], dopamine [15] and phenol [16] shown in Table 17.2 operate on the same principle as the biosensor for L-ascorbic acid [11],... 

Tissue-based biosensors provide potential advantages of low cost, high stability, longer lifetime and a high level of activity. This is in part due also to the fact that the enzymes can find cofactors in the natural microenvironment. 

Of all types of biosensors, metabolism sensors based on the molecular analyte recognition and conversion have been most intensively studied. According to the degree of integration of the biocomponents they can be classified into monoenzyme sensors, biosensors using coupled enzyme reactions, organelle, microbial, and tissue-based sensors. The sequence of the following sections corresponds to this classification. 

Slices and other parts of tissues of animal or plant origin are the most complex biosystems so far applied in biosensors. Tissues containing large amounts of the enzymes of interest have been deliberately used. An overview of tissue-based sensors is given in Table 18. 

First tissue-based biosensor antennules from blue crabs mounted in a chamber with a platinum electrode to detect amino acids [18]... 

Sanders CA, Rodriguez M, Greenbaum E. Stand-off tissue-based biosensors for the detection of chemical warfeie agents using photosynthetic fluorescence induction. Biosens Bioelectron 2001 16 439-446. 

Wang J., Kane S. A., Liu J., Smyth M. R., and Rogers K. R., Mushroom tissue-based biosensor for inhibitor monitoring, Food Technology and Biotechnology, 34, 51-55,... 

Various types of biocatalytic materials, such as isolated enzymes, bacterial cells, and intact mammalian and plant tissue sections, are available for the preparation of biocatalytic-based biosensors (3-7), An enzyme, or a group of enzymes, provides the required biocatalytic activity. For the bacterial cell and tissue based systems, the required enzyme is housed in these biocatalytic materials which can help stabilize the enzyme and prolong the biocatalytic activity. 

Several biological materials, such as animal tissues, bacterial cells, and plant tissues, have been used for this purpose. In earlier studies, animal materials, such as heart, liver, and kidney, were used exclusively for the construction of biosensors. However, since the introduction of the first plant-tissue-based electrochemical biosensor by Kuriyama and Rechnitz in 1981, the use of plant tissues has attracted the most interest for the development of tissue-based biosensors. The popularity of the use of plant tissues as natural enzyme sources for the construction of biosensors was further enhanced by the introduction of a banana tissue biosensor, known as the bananat-rode , in 1985. Since then several other plant tissues, such as fruits, leaves, roots, seeds, and vegetables, as listed in Table 1, have been used for the development of a wide range of tissue-based biosensors. 

Plant leaves have attracted considerable interest in the development of tissue-based biosensors because of their unique natural structural arrangement. The... 

Table 1 Some of the reported plant-tissue-based biosensors ...

Another notable disadvantage of tissue-based biosensors is that their use is sometimes limited by interference from other enzymes or substances present in the tissues. However, several new approaches have reported for reducing these effects and in some cases taking advantage of the copresence of more than one enzyme for multicomponent analysis or the elimination of an interferant(s). 

The principles and some of the important considerations in the development and use of tissue-based biosensors are described below. Also, some specific examples of the existing tissue-based biosensors that have employed a wide range of plant and animal tissues for the detection of a wide range of substances are discussed. 

The working principles and operation of tissue-based biosensor are similar in many respects to those of the... 

Figure 1 Schematic diagram of the arrangement of a tissue-based membrane biosensor (A) slice of tissue (B) bovine serum albumin conjugate layer (C) carbon dioxide gas permeable membrane (D) 0-ring (E) internal electrolyte solution (F) pH-sensing glass membrane (G) plastic electrode body. (Reproduced with permission from Kurlyama S and Rechnitz GA (1981) Analytica Chimica Acta 131 91.)...

The potential for the coexistence of several enzymes in tissue materials can also be a major drawback as it can affect the selectivity of the device when used in complex sample media. Some of the strategies that have been employed for improving the selectivity of tissue-based biosensors include the use of activators to promote the primary reaction, inhibitors to suppress the undesirable reactions, or preincubation of the desired substrate. Under favorable conditions, the multienzyme activity of the tissue can be exploited for the detection of multicomponents in real samples. For example, with amperometric detection, such multicomponent detection may require the application of different potentials to achieve improved selectivity. 

Besides the availability of plant and animal tissues that contain the necessary enzymes and the associated issues with their use as described above, some of the other important considerations in the development and use of tissue-based biosensors include immobilization method, response time, and lifetimes. The significance of each of these factors is discussed below. 

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