Polymeric Biosensors

Gunderson, HW. Gunderson, ER. Ferguson, Food Standards and Definition in the United States , Academic Press, NY, 1963 

CRC Handbook of Food Additives , 2nd edn, CRC Press, Boca Raton, FF, 1975 

Leonard, Macromolecular control of food additives , in Polymeric Delivery Systems , RJ. Kostelnik, ed, Gordon Breach, NY, pp. 269-90, 1978 

Langer, Flavor Encapsulation , ACS Symposium Series, 370, Chap 18, p 177-191, 1988 

Richardson, NF. Olson, in Immobilized Enzymes in Food and Microbial Processes , 

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Polymer libraries are covered according to their numerous applications, each described through a specific example. The reported examples include libraries of copolymers as liquid/solid supports with different compositions, libraries of biodegradable materials for clinical applications, libraries of stationary phases for GC/LC separations, libraries of polymeric reagents or catalysts, libraries of artificial polymeric receptors or molecularly imprinted polymers, and libraries of polymeric biosensors. The opportunities that could arise in the near future from novel applications of polymer libraries are also briefly discussed. 

Kumpumbu-Kalemba, L., and M. Leclerc. 2000. Electrochemical charcaterization of monolayers of biotinylated polythiophene Towards the development of polymeric biosensors. Chem Commun 1847-1848. 

L. Kumpumbu-Kalemba, M. Leclerc, Electrochemical characterization of monolayers of a biotinylated polythiophene towards the development of polymeric biosensors, Chemical Communications 2000, 1847. 

Spectroscopic evalnatimi of protein affinity binding at polymeric biosensor films. J Am Chem Soc 121 4302-4303. doi 10.1021/ja984467-t... 

Pan, G., Zhang, Y, Guo, X., Li, C., and Zhang, H. 2010. An efficient approach to obtaining water-compatible and stimuli-responsive molecularly imprinted polymers by the facile surface-grafting of fimctional polymer brushes via RAFT polymerization. Biosensors and Bioelectronics 26 976-82. 

Schematic diagram illustrating the process of immobilization of trichlorosilane coupling agent on the ITO surface, surface-initiated ATRP of GMA from the ITO-Cl surface to produce the inner block, followed by block copolymer of FMMA and the coupling of GOD to the epoxide groups of the P(GMA) (scheme 1). In scheme 2, P(FMMA) is first grafted from the ITO-Gl surface, and the P(GM A) segment is then grafted as the outer block of the copolymer. (Reproduced from Zhang et al. 2010. Enzyme-mediated amperometric biosensors prepared via successive surface-initiated atom-transfer radical polymerization. Biosensors Bioelectronics 25 (5) 1102-1108, with permission from Elsevier.)...

Functionalized conducting monomers can be deposited on electrode surfaces aiming for covalent attachment or entrapment of sensor components. Electrically conductive polymers (qv), eg, polypyrrole, polyaniline [25233-30-17, and polythiophene/23 2JJ-J4-j5y, can be formed at the anode by electrochemical polymerization. For integration of bioselective compounds or redox polymers into conductive polymers, functionalization of conductive polymer films, whether before or after polymerization, is essential. In Figure 7, a schematic representation of an amperomethc biosensor where the enzyme is covalendy bound to a functionalized conductive polymer, eg, P-amino (polypyrrole) or poly[A/-(4-aminophenyl)-2,2 -dithienyl]pyrrole, is shown. Entrapment of ferrocene-modified GOD within polypyrrole is shown in Figure 7. 

Oxidation of P-nicotinamide adenine dinucleotide (NADH) to NAD+ has attracted much interest from the viewpoint of its role in biosensors reactions. It has been reported that several quinone derivatives and polymerized redox dyes, such as phenoxazine and phenothiazine derivatives, possess catalytic activities for the oxidation of NADH and have been used for dehydrogenase biosensors development [1, 2]. Flavins (contain in chemical structure isoalloxazine ring) are the prosthetic groups responsible for NAD+/NADH conversion in the active sites of some dehydrogenase enzymes. Upon the electropolymerization of flavin derivatives, the effective catalysts of NAD+/NADH regeneration, which mimic the NADH-dehydrogenase activity, would be synthesized [3]. 

Since ideally, a biosensor should be reagentless, that is, should be able to specifically measure the concentration of an analyte without a supply of reactants, attempts to develop such bioluminescence-based optical fibre biosensors were made for the measurements of NADH28 30. For this purpose, the coreactants, FMN and decanal, were entrapped either separately or together in a polymeric matrix placed between the optical fibre surface and the bacterial oxidoreductase-luciferase membrane. In the best configuration, the period of autonomy was 1.5 h during which about twenty reliable assays could be performed. 

Michel P.E., Gautier S.M., Blum L. J., Luciferin incorporation in the structure of acrylic microspheres with subsequent confinement in a polymeric film a new method to develop a controlled release- based biosensor for ATP, ADP and AMP, Talanta 1998 47 167-181. 

Jung, S.K., and Wilson, G.S. (1996) Polymeric mercaptosilane-modified platinum electrodes for elimination of interferants in glucose biosensors. Anal Chem. 68(4), 591-596. 

Challenges remain in the development of lab-on-a-chip sensing systems. The overall lifetime of a sensor chip is always determined by the sensor with the shortest lifetime, which in most cases is the depletion of reference electrolytes. Measures to minimize cross-talking among sensors, especially when biosensors are integrated in the system, also should be implemented [122], The development of compatible deposition methods of various polymeric membranes on the same chip is another key step in the realization of multisensing devices. 

Among various enzyme immobilization protocols, entrapment in polymer membranes is a general one for a variety of transducers. Formation of a membrane from a solution of already synthesized polymer is simpler and reproducible compared to chemical polymerization. The simplicity of this immobilization procedure should provide reproducibility for the resulting biosensors the latter is strongly required for mass production. 

Catalytic biosensors, 3 796-799 Catalytic chain transfer polymerization (CCTP), 20 442, 444... 

Horseradish peroxidase (HRP) is an extracellular plant enzyme that acts in regulation of cell growth and differentiation, polymerization of cell wall components, and the oxidation of secondary metabolites essential for important pathogenic defense reactions. Because of these essential functions, and also because of its stability and ready availability, HRP has attracted considerable attention.13 It has been involved in a number of applications, such as diagnostic assays,14 biosensors,15 bioremediation,16 polymer synthesis,17 and other biotechnological processes.18 More applications in which HRP catalysis is translated into an electrochemical signal are likely to be developed in the near future. 

Many different polymer matrices have been reported in the literature. The use of polyvinyl alcohol (PVA) as a matrix has been reported in the construction of a biosensor specific toNADH.(71) A detailed summary of the polymerization of PVA and the attachment of fluorescein to this polymer was reported by Seitz. 22 Plasticized polyvinyl chloride (PVC) has been used for the detection of lead. 72 PVC was also... 

X-streptavidin. The intricate interplay between the steric and electronic properties of the acceptor and the polymeric donor may have important impact for the design of future biosensors. 

The polyamide is a substituted nylon 2, that is, it is derived from an a-amino acid—the same type used in living organisms to produce polypeptides. NCA polymerizations have been used to synthesize polypeptides, both homopolymers and copolymers, that may be useful in biotechnology applications such as artificial tissues, drug delivery, and biosensors. 

Jelinek R, Kolusheva S. Polymerized hpid vesicles as colorimetric biosensors for biotechnological applications. Biotechnol Adv 2001 19 109-118. 

SCHEME 8. Operation of the biosensor based on an electrode coated by a polymeric film containing both immobilized HRP and iron ions. The organic peroxide acts as a reducing agent... 

The mimetic biosensor for ELD described in Section ni.B.4.b, incorporating polymerized Fe-protoporphyrin IX (75c) and Os(II) ions, can be used for determination of diacyl peroxides in organic solution. The electrode was tested for determination of BzOOBz extracted from a pharmaceutical geP. ... 

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