Electrode screen-printed

Moreover, disposable electrochemical sensors for the detection of a specific sequence of DNA were realised by immobilising synthetic single-stranded oligonucleotides onto a graphite or a gold screen-printed electrode. Tire probes became hybridised with different concentrations of complementary sequences present in the sample. 

Biosensors ai e widely used to the detection of hazardous contaminants in foodstuffs, soil and fresh waters. Due to high sensitivity, simple design, low cost and real-time measurement mode biosensors ai e considered as an alternative to conventional analytical techniques, e.g. GC or HPLC. Although the sensitivity and selectivity of contaminant detection is mainly determined by a biological component, i.e. enzyme or antibodies, the biosensor performance can be efficiently controlled by the optimization of its assembly and working conditions. In this report, the prospects to the improvement of pesticide detection with cholinesterase sensors based on modified screen-printed electrodes are summarized. The following opportunities for the controlled improvement of analytical characteristics of anticholinesterase pesticides ai e discussed ... 

AN AMPEROMETRIC ENZYME IMMUNOSENSOR BASED ON SCREEN-PRINTED ELECTRODE FOR THE DETERMINATION OF KLEBSIELLA PNEUMONIAE BACTERIAL ANTIGEN... 

The aim of our investigation was the development of the amperometric enzyme immunosensor for the determination of Klebsiella pneumoniae bacterial antigen (Ag), causes the different inflammatory diseases. The biosensing pail of the sensors consisted of the enzyme (cholinesterase) and antibodies (Ab) immobilized on the working surface of the screen-printed electrode. Bovine seiaim albumin was used as a matrix component. 

Palchetti I, Mascini M (2005) Electrochemical Adsorption Technique for Immobilization of Single-Stranded Oligonucleotides onto Carbon Screen-Printed Electrodes. 261 27-43 Pascal R, Boiteau L, Commeyras A (2005) From the Prebiotic Synthesis of a-Amino Acids Towards a Primitive Translation Apparatus for the Synthesis of Peptides. 259 69-122 Paulo A, see Santos I (2005) 252 45-84 Perez EM, see Leigh DA (2006) 265 185-208 Perret F, see Coleman AW (2007) 277 31-88 Perron H, see Coleman AW (2007) 277 31-88 Pianowski Z, see Winssinger N (2007) 278 311-342 Piestert F, see Gansauer A (2007) 279 25-52... 

MWNTs favored the detection of insecticide from 1.5 to 80 nM with a detection limit of InM at an inhibition of 10% (Fig. 2.7). Bucur et al. [58] employed two kinds of AChE, wild type Drosophila melanogaster and a mutant E69W, for the pesticide detection using flow injection analysis. Mutant AChE showed lower detection limit (1 X 10-7 M) than the wild type (1 X 10 6 M) for omethoate. An amperometric FIA biosensor was reported by immobilizing OPH on aminopropyl control pore glass beads [27], The amperometric response of the biosensor was linear up to 120 and 140 pM for paraoxon and methyl-parathion, respectively, with a detection limit of 20 nM (for both the pesticides). Neufeld et al. [59] reported a sensitive, rapid, small, and inexpensive amperometric microflow injection electrochemical biosensor for the identification and quantification of dimethyl 2,2 -dichlorovinyl phosphate (DDVP) on the spot. The electrochemical cell was made up of a screen-printed electrode covered with an enzymatic membrane and combined with a flow cell and computer-controlled potentiostat. Potassium hexacyanoferrate (III) was used as mediator to generate very sharp, rapid, and reproducible electric signals. Other reports on pesticide biosensors could be found in review [17],... 

S. Andreescu, L. Barthelmebs, and J.L. Marty, Immobilization of acetylcholinesterase on screen-printed electrodes comparative study between three immobilization methods and applications to the detection of organophosphorus insecticides. Anal. Chim. Acta 464, 171—180 (2002). 

E.V. Gogol, G.A. Evtugyn, J.L. Marty, H.C. Budnikov, and V.G. Winter, Amperometric biosensors based on Nafion coated screen-printed electrodes for the determination of cholinesterase inhibitors. Talanta 53, 379-389 (2000). 

A. Ivanov, G. Evtugyn, L.V. Lukachova, E.E. Karyakina, HC. Budnikov, S.G. Kiseleva, A.V. Orlov, G.P. Karpacheva, and A.A. Karyakin, Cholinesterase potentiometric sensor based on graphite screen-printed electrode modified with processed polyaniline. IEEE Sensors J. 3, 333-340 (2003). 

A. Ivanov, G. Evtugyn, H. Budnikov, F. Ricci, D. Moscone, and G. Palleschi, Cholinesterase sensors based on screen-printed electrodes for detection of organophosphorus and carbamic pesticides. Anal. Bioanal. Chem. 377, 624-631 (2003). 

F. Darain, S.-U. Park, and Y.-B. Shim, Disposable amperometric immunosensor system for rabbit IgG using a conducting polymer modified screen-printed electrode. Biosens. Bioelectron. 18, 773—780 (2003). 

S. Centi, S. Laschi, M. Franek, and M. Mascini, A disposable immunomagnetic electrochemical sensor based on functionalized magnetic beads and carbon-based screen-printed electrodes (SPCEs) for the detection of polychlorinated biphenyls (PCBs). Anal. Chim. Acta 538, 205—212 (2005). 

J.M. Zen, P.Y. Chen, and A.S. Kumar, Flow injection analysis of an ultratrace amount of arsenite using a Prussian blue-modified screen-printed electrode. Anal. Chem. 75, 6017-6022 (2003). 

The fouling and microbial contamination of the surface during operation are main problems in the long-term use of enzyme biosensors. Wang et al. [121] reported for the first time a screen-printed electrode modified with GOD/HRP that was stable up... 

Making Reference Electrodes Microelectrodes Screen-Printed Electrodes... 

Recently, some papers have started to highlight the performance of PSf-(bio) composites-CNT as electrode material for electrochemical immunosensing [112]. The authors have highlighted the attractive combination of PSf/CNTplus disposable screen-printed electrodes for monitoring the errzymatic activity of horseradish peroxidase and the RIgG inmunosensor response. In both cases an enhanced electroanalytical response was demonstrated in comparison with standard graph-ite/PSf composites. 

As an example. Figure 54a shows the zero-bias impedance of LSC electrodes on rare-earth-doped ceria in air at 750 °C measured using a symmetric cell incorporating a traditional reference electrode. Although the two screen-printed electrodes (1 and 2) were processed identically and aligned to an accuracy of 0.1 mm, the cell response is highly asymmetric... 

Electrochemical Adsorption Technique for Immobilization of Single-Stranded Oligonucleotides onto Carbon Screen-Printed Electrodes I. Palchetti M. Mascini... 

Kroger S, Turner APF, Mosbach K, Haupt K. Imprinted polymer based sensor system for herbicides using differential-pulse voltammetry on screen printed electrodes. Anal Chem 1999 71 3698-3702. 

Voltammetric/Amperometric Sensors Thick-film carbon-containing screen-printed electrodes modified with formazan [473] were used for zinc determination. 

Ricci et al. [13] Beverages Glucose oxidase (GOx)/ with glutaraldehyde and Nafion Prussian Blue (PB)-modified glassy carbon (PB-GC) particles screen-printed electrodes/-0.05 V vs. Ag/AgCl Prussian Blue... 

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