Biosensor commercial

Chemical sensor and biosensor commercialization must also pass a difficult set of criteria and questions at every point of development. These questions are aimed at measuring current and future technical and market performance for the sensor and include the following. 

Market and business issues have also slowed chemical sensor and biosensor commercialization. As often occurs with technologies encompassing many disciplines, problems with patents and proprietary technology protection have appeared. For example, one common transducer used for both chemical sensors and biosensors is the integrated electrode capacitor (see chapter 8 for a description of this transducer). Although the design for this transducer has been in the public domain for over 25 years, chemical modification of the surface characteristics of the electrodes can lead to a new patent position. This then leads to complex claims and counterclaims about the use of the basic transducer technology. 

Much of the motivation for the study of XO electrochemistry is the development of amperometric biosensors. Commercially available bovine XO is invariably the enzyme of choice used in these applications. High levels of hypoxanthine are linked with asphyxia in newborns, SIDS and hypoxia in general. Coupled with other enzymes, such as purine nucleoside phos-phorylase, XO can be used to determine phosphate coneentrations in clinical, food and waste samples. Purine nueleoside phosphorylase catalyzes the phosphorylation of inosine liberating hypoxanthine and ribose-l-phosphate (Scheme 5.5). In the presence of XO, hypoxanthine is oxidized to xanthine and produces one equivalent of H2O2. Thus due to the stoichiometry of the reaction one equivalent of H2O2 is produced for every phosphate anion present. ... 

The recent developments in electrochemical studies of redox enzymes have opened a whole new horizon for biosensor development for a variety of analytical applications. However, a lot of research is still required to find potential biocatalysts for a number of analytes that need constant monitoring and to make electrochemical biosensors commercially successful bioanalytical device. 

Few potentiometric biosensors are commercially available. As shown in Figures 11.16 and 11.17, however, available ion-selective and gas-sensing electrodes may be easily converted into biosensors. Several representative examples are described in Table 11.5, and additional examples can be found in several reviews listed in the suggested readings at the end of the chapter. 

This experiment describes the use of a commercially available amperometric biosensor for glucose that utilizes the enzyme glucose oxidase. The concentration of glucose in artificial... 

Commercially available kits for monitoring blood-glucose use an amperometric biosensor incorporating the enzyme glucose oxidase. This experiment describes how such monitors can be adapted to the quantitative analysis of glucose in beverages. 

As of this writing chemoreceptor-based biosensors are not yet on the commercial market. Only a few chemoreceptors have been isolated and their substrates identified. Moreover, those chemoreceptors that have been isolated are fragile and have limited lifetimes. 

A lot of analytical techniques have been proposed in recent decades and most of them are based on enzymes, called dehydrogenases, which are not sensitive to oxygen and need cofactors such as NAD". The key problems which seriously hamper a wide commercialization of biosensors and enzymatic kits based on NAD-dependent enzymes are necessity to add exogenous cofactor (NAD" ) into the samples to be analyzed to incorporate into the biologically active membrane of sensors covalently bounded NAD" to supply the analytical technique by NAD -regeneration systems. 

Several biosensors are commercially available. One of the most useful is the glucose sensor. The standard sensor determines glucose concentration based on the glucose oxidase enzyme. The chemical reaction for oxidation of glucose is ... 

Vol. 148. Commercial Biosensors Applications to Clinical, Bioprocess and Environmental Samples. Edited by Graham Ramsay... 

New developments in immobilization surfaces have lead to the use of SPR biosensors to monitor protein interactions with lipid surfaces and membrane-associated proteins. Commercially available (BIACORE) hydrophobic and lipophilic sensor surfaces have been designed to create stable membrane surfaces. It has been shown that the hydrophobic sensor surface can be used to form a lipid monolayer (Evans and MacKenzie, 1999). This monolayer surface can be used to monitor protein-lipid interactions. For example, a biosensor was used to examine binding of Src homology 2 domain to phosphoinositides within phospholipid bilayers (Surdo et al., 1999). In addition, a lipophilic sensor surface can be used to capture liposomes and form a lipid bilayer resembling a biological membrane. 

While several optical chemical sensors and biosensors in use that do not rely on fiber optics, the commercialization of FOCS technology started slowly, probably because of the limitations imparted to optical sensing if... 

Main types of biomolecular recognition elements used in affinity biosensors based on spectroscopy of guided modes include antibodies, nucleic acids and biomimetic materials. Antibodies are used most frequently because of their high affinity, versatility, and commercial availability. 

A feature of biosensors that should be more fully appreciated by the counterterrorism community is their potential for dual use. Not only will commercial production be more sustainable if there is also a civilian application that produces a steady market demand, but users will have more confidence in a system that becomes thoroughly validated in a more predictable application. If the civilian application is one that also employs potential first responders, such as emergency room staff, veterinarians, or water treatment technicians, such individuals will more fully appreciate the value and limits of the technology. 

The cholinesterase to determine the toxic activity may be chosen (i) in pure form of commercial enzyme from animals in a water buffer solution or using biosensors, enzyme preparation impregnated into a rigid matrix that significantly activates the enzymic activity and (ii) in the form of crude extracts from plant or animal tissues. 

P.R.B. de O Marques, G.S. Nunes, T.C.R. dos Santos, S. Andreescu, and J.L. Marty, Comparative investigation between acetylcholinesterase obtained from commercial sources and genetically modified Drosophila melanogaster application in amperometric biosensors for methamidophos pesticide detection. Biosens. Bioelectron. 20, 825-832 (2004). 

FIGURE 3.4 A typical commercial strip for self-testing of blood glucose (based on a biosensor manufactured by Abbott Inc.) (see Plate 1 for the color version). 

J.D. Newman and A.P.F. Turner, Home blood glucose biosensors a commercial prospective. Biosensors and Bioelectronics 20, 2388-2403 (2005). 

SOD comprises a family of metalloproteins primarily classified into four groups copper, zinc-containing SOD (Cu, Zn-SOD), manganese-containing SOD (Mn-SOD), iron-containing SOD (Fe-SOD) and nickel-containing SOD (Ni-SOD). In the following studies, we will only focus on the uses of the former three kinds of SODs to construct SOD-based 02 biosensors since the last one, Ni-SOD, is not commercially available. 

More than 90% of commercially available enzyme-based biosensors and analytical kits contain oxidases as terminal enzymes responsible for generation of analytical signal. These enzymes catalyze oxidation of specific analyte with molecular oxygen producing hydrogen peroxide according to the reaction ... 

The introduction of optical biosensors has made it possible to obtain data for a large number of macromolecular interactions without the necessity of additional labeling. Here several commercial instruments utilize the effect of Surface Plasmon Resonance (SPR) to detect accumulation of ligands in the sensor matrix. 

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