Biosensor enzyme inhibition-based

Survey of enzyme inhibition based biosensors for heavy metals for the last 5 years... 

M.D. Luque de Castro and M.C. Herrera, Enzyme inhibition-based biosensors and biosensing systems questionable analytical devices, Biosens. Bioelectron., 18 (2003) 279-294. 

A. Amine, H. Mohammadi, I. Bourais and G. Palleschi, Enzyme inhibition based biosensors for food safety and environmental monitoring (review), Biosens. Bioelectron., 21 (2005) 1405-1423. 

M. Campas, D. Szydlowska, M. Trojanowicz and J.-L. Marty, Enzyme inhibition-based biosensor for the electrochemical detection of microcystins in natural blooms of cyanobacteria (2006), submitted for publication. 

T. M. Park, E. I. Iwuoha, M. R. Smyth, Development of a Sol-gel Enzyme Inhibition-based Amperometric Biosensor for Cyanide. Electroanalysis, 9 (1997) 1120-1123. 

Sheo, L., Upadhyay, B., Verma, N., 2013. Enzyme inhibition based biosensors a review. Anal. Lett. 46, 225-241. 

Amine A, Mohanunadi H, Bourais I, Palleschi G (2006) Enzyme inhibition-based biosensors f(OT food safely and envirraunental monitoring. Biosens Bioelectron 21 1405-1423... 

A huge number of methods based on enzyme inhibition-based biosensors can be found in the literature. Most times (57.6 %) acetylcholinesterase, butyrylchoU-nesterase, or cholinesterase are used followed by t3Tosinase (13 %) mainly combined with electrochemical procedures (44.5 % amperometric, 35.8 % potentiometric, frequently based on oxygen and pH measurements, and, to a very less extent, piezoelectrical). 

One of the most regrettable characteristics of enzyme inhibition-based biosensors is the different inhibition degree caused by different inhibitors. An example of this behavior is an amperometric acid phosphatase inhibition-based biosensor proposed by Mazzei et al., which shows different inhibition efficiency towards organophosphorus and carbamate compounds (the latter with a weaker inhibition efficacy and higher detection limits, as a result). 

Most of the pesticide biosensors are designed based on the inhibitory property of enzymes. AChE and butyrylcholinesterase (BChE) are widely used in the development of pesticide biosensors [17, 18], Inhibition leads to a decrease in activity, which... 

Mainly, two principles are used in electrochemical pesticide biosensor design, either enzyme inhibition or hydrolysis of pesticide. Among these two approaches inhibition-based biosensors have been widely employed in analysis due to the simplicity and wide availability of the enzymes. The direct enzymatic hydrolysis of pesticide is also extremely attractive for biosensing, because the catalytic reaction is superior and faster than the inhibition [27],... 

Although the inhibition-based biosensors are sensitive, they are poor in selectivity and are rather slow and tedious since the analysis involves multiple steps of reaction such as measuring initial enzyme activity, incubation with inhibitor, measurement of residual activity, and regeneration and washing. Biosensors based on direct pesticide hydrolysis are more straightforward. The OPH hydrolyzes ester in a number of organophospho-rus pesticides (OPPs) and insecticides (e.g. paraoxon, parathion, coumaphos, diazinon) and chemical warfare agents (e.g. sarin) [53], For example, OP parathion hydrolyzes by the OPH to form p-nitrophenol, which can be measured by anodic oxidation. Rainina... 

T. Noguer, B. Leca, G. Jeanty, and J.L. Marty, Biosensors based on enzyme inhibition detection of organophosphorus and carbamate insecticides and dithiocarbamate fungicides. Field Anal. Chem. Tech. 3, 171-178 (1999). 

W.E. Lee, H.G. Thompson, J.G. Hall and D.E. Bader, Rapid detection and identification of biological and chemical agents by immunoassay, gene probe assay and enzyme inhibition using a silicon-based biosensor, Biosens. Bioelectron., 14(10-11) (2000) 795-804. 

Electrochemical biosensors for heavy metals based on enzyme inhibition... 

ANALYTICAL CHARACTERIZATION OF BIOSENSORS-BASED ENZYME INHIBITION... 

Biosensors based on enzyme inhibition are still limited in analytical applications since these sensor technologies are not usually able to discriminate various toxic compounds in the same sample. 

P.W. Alexander and G.A. Rechnitz, Enzyme inhibition assays with an amperometric glucose biosensor based on thiolate self-assembled mono-layer, Electroanalysis, 12 (2000) 343-350. 

Z. Guang-Ming, T. Lin, S. Guo-Li, H. Guo-He and N. Cheng-Gang, Determination of trace chromium (VI) by an inhibition-based enzyme biosensor incorporating an electro polymerized aniline membrane and... 

H. Mohammadi, A. Amine, S. Cosnier and C. Mousty, Mercury-enzyme inhibition assays with an amperometric sucrose biosensor based on a trienzymatic-clay matrix, Anal. Chim. Acta, 543 (2005) 143-149. 

Determination of methyl mercury using biphasic system (aqueous solution/ solvent) in the presence of fish matrix. The method is based on enzyme inhibition combined with glucose oxidase biosensor... 

The principle of combination of electrochemical glucose oxidase biosensor with the clean-up method for direct extraction and determination of methyl mercury has been successfully demonstrated. The extraction of methyl mercury from the organic solvent has been based on invertase enzyme inhibition. The combination of very low concentration of invertase enzyme and 10 min of incubation time allows the detection of methyl mercury at 5 ppb level. Our method permits the detection of this inhibitor below the legal limit given by the European Union with good recoveries when fish samples were measured. 

Although the main analytes that are determined by enzyme biosensor are substrates of enzymes, numerous attempts were reported in the literature about using them for indirect determination of inhibitors.112113 Such determination can be also carried out in organic solvents.114 Many of such inhibition-based methods can be questioned because of numerous fundamental and practical disadvantages.115 These are, for instance, difficult or more often impossible regeneration of inhibited enzymes, and the fact that different inhibition degree is caused by different inhibitors. One can find example that in some cases, better results are obtained with the use of raw tissues when compared with purified enzyme.116 It was also pointed out that the most rational use of inhibitory effects is after a separation step for proper removal of species, which can act on the activity of enzyme. 

Enzyme inhibition sensors are the most commonly reported enzyme-based biosensors for the detection of toxic compounds and heavy metal ions. The sensors are based on the selective inhibition of specific enzymes by classes of compounds or by the more general inhibition of enzyme activity. Most of the research carried out has been directed toward the detection of organophosphorus and carbamate insecticides and the triazine herbicides and metal ions analysis [72,73]. Several enzymes have been used in inhibition sensors for pesticides and heavy metal analysis using water, soil, and food samples including choline esterase, horseradish peroxidase, polyphenol oxidase, urease, and aldehyde dehydrogenase. 

Limitations for biosensors based on enzyme inhibition is that the assay may need multistep incubation, and the assay formats require the use of substrates/cofactors and mediators depending on the enzyme applied in the sensor format. The irreversible... 

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