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1

Surface plasmon resonance imaging biosensors for aromatase based on a potent inhibitor and a specific antibody: Sensor development and application for biological material

100%

Gorodkiewicz E., Sankiewicz A., Laudański P.

Open Chemistry

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2014

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vol. 12

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issue 5

557-567

EN

Aromatase (ARO) is an enzyme with potential diagnostic significance. Aberrant expression of aromatase in tissues is associated with a number of pathological conditions, including tumor of the breast, ovary, testes, liver, adrenal cortex and uterus, as well as endometriosis. Two methods for the highly selective determination of ARO concentration in human tissues by using of two different biosensors co-operating with the surface plasmon resonance imaging technique (SPRI) have been developed. One of the developed biosensors contains immobilised rabbit polyclonal antibody specific for aromatase (Y-ARO), while the other contains immobilized ARO inhibitor-exemestane (E-ARO). Both biosensors specifically bound ARO from analyzed samples. The analytically useful dynamic response range of both biosensors is between 0.3 and 5.0 ng mL−1. The detection limit (3S.D.) of both biosensors is 90 pg mL−1. Standard deviation of both biosensors is 1%. Recoveries of ARO spikes are between 97 and 108% for both biosensors under model conditions and for real samples. Albumin and alkaline phosphatase are tolerated for both biosensors up to 10,000 fold excess.

2

Design of an amperometric xanthine biosensor based on a graphite transducer patterned with noble metal microparticles

100%

Dodevska T., Horozova E., Dimcheva N.

Open Chemistry

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2010

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vol. 8

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issue 1

19-27

EN

A mesoporous graphite material micro-structured with palladium-platinum deposits (mixed in the ratio of 70:30% Pd:Pt) has been used as a cost-effective electrode material for designing an amperometric biosensor for xanthine. The here reported biosensor shows significantly improved operational parameters as compared to previously published results. At a constant applied potential of −0.05 V (vs. Ag/AgCl) it is distinguished with enhanced selectivity of the determination: at the working potential the current from the electrochemical transformation of various electrochemically active substances usually attending biological fluids (incl. uric acid, L-ascorbic acid, glutathione and paracetamol) has been eliminated. The effect of both the temperature and buffer composition on the analytical performance of the sensor has been investigated. Under optimal operational conditions (25°C, −0.05 V vs. Ag/AgCl, phosphate buffer, pH 8.4), the following have been defined for the biosensor: sensitivity 0.39 µA µM−1, strict linearity of the response up to xanthine concentration 70 µM, detection limit of 1.5 µM (S/N=3) and a response time of at most 60 s. [...]

3

Rapid flow injection electrochemical detection of 3,3′,4,4′ tetrachlorobiphenyl using stabilized lipid membranes with incorporated sheep antibody

100%

Nikolelis D., Psaroudakis N., Michaloliakos A., Nikoleli G.-P., Scoullos M.

Open Chemistry

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2013

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vol. 11

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issue 2

320-323

EN

An electrochemical biosensor based on a supported polymerized lipid film with incorporated sheep anti-3,3′,4,4′ tetrachlorobiphenyl (PCB congener 77) antibody using flow injection analysis was developed. The polymerized lipid film contained 85% (w/w) dipalmitoylphosphatidylcholine (DPPC) and 15% (w/w) dipalmitoylphosphatidic acid (DPPA), methacrylic acid, ethylene glycol dimethacrylate, AIBN and sheep anti-congener 77 antiserum. Congener 77 was injected into flowing carrier electrolyte and the flow stopped to detect the antigen. These membranes gave only a single transient proportional to log [congener 77] from 10−8 to 10−5 M, with a detection limit of ca. 10−8 M. A membrane containing 35% (w/w) DPPA was used to examine regeneration. The maximum number of cycles was about 5. [...]

4

Enantioselective inhibition of immobilized acetylcholinesterase in biosensor determination of pesticides

100%

Kaniewska M., Jońca J., Połeć I., Sikora T., Marty J.-L., Trojanowicz M.

Open Chemistry

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2012

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vol. 10

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issue 6

1760-1765

EN

Chiral effects for the inhibition of acetylcholinesterase by organophosphorus pesticides were investigated for insecticide malathion and malaoxon, which is a metabolic product of malathion in living organisms. Studies were carried out using a bienzymatic biosensor with immobilized acetylcholinesterase, choline oxidase, and with Prussian Blue used as a mediator. In both cases the R enantiomers accelerate acetylocholinesterase inhibition. The chiral effect in inhibition was much more pronounced in fast flow measurements than in batch measurements. [...]

5

Kinetic study of the decomposition of Prussian Blue electrocatalytic layer during cathodic reduction of hydrogen peroxide

100%

Araminaitė R., Garjonytė R., Malinauskas A.

Open Chemistry

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2008

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vol. 6

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issue 2

175-179

EN

Kinetic study on the decomposition of Prussian Blue electrocatalytic layer during electrochemical reduction of hydrogen peroxide has been studied in relation to biosensor application of this electrocatalyst. The decomposition has been shown to proceed as a nearly exponential decay process and the corresponding first-order rate coefficients were determined. It has been shown that the decomposition proceeds about 10 times faster in pH 7.3 buffer solution as compared to pH 5.5 buffer. A linear dependence of the decomposition rate on the concentration of hydrogen peroxide has been found. [...]

6

Comparison of biosensors based on gold and nanocomposite electrodes for monitoring of malic acid in wine

100%

Monošík R., Streďanský M., Greif G., Šturdík E.

Open Chemistry

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2012

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vol. 10

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issue 1

157-164

EN

Amperometric biosensors based on a gold planar electrode and on two types of nanocomposite electrodes consisting of multi-walled carbon nanotubes for the determination of L-malic acid designed for wine-makers were developed. The biosensors designed for wine-makers were constructed by immobilization of L-malate dehydrogenase and diaphorase within chitosan layers on the surface of the electrodes. The coenzyme NAD+ and the electrochemical mediator ferricyanide were present in the measuring solution. The current resulting from re-oxidation of produced ferrocyanide was measured at a working potential of +300 mV against an Ag/AgCl reference electrode. The biosensor based on a gold electrode showed linearity over the range 10–520 µM with a detection limit of 5.41 µM. Calibration curves for biosensors utilizing nanocomposites were obtained both with the linear range of 10 to 610 µM. The detection limits were 1.57 and 1.77 µM, respectively. The biosensors showed satisfactory operational stability (no loss of sensitivity after 30 consecutive measurements) and storage stability (90% of the initial sensitivity after one year of storage at room temperature). The results obtained from measurements of wine samples were in a good correlation with the standard HPLC method. Satisfactory biosensor sensitivity, specificity and stability allowed their successful commercialization.

7

Integrated optical biosensor for rapid detection of bacteria

86%

Mathesz A., Valkai S., Újvárosy A., Aekbote B., Sipos O., Stercz B., Kocsis B., Szabó D., Dér A.

Optofluidics, Microfluidics and Nanofluidics

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2015

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vol. 2

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issue 1

EN

In medical diagnostics, rapid detection of pathogenic bacteria from body fluids is one of the basic issues. Most state-of-the-art methods require optical labeling, increasing the complexity, duration and cost of the analysis. Therefore, there is a strong need for developing selective sensory devices based on label-free techniques, in order to increase the speed, and reduce the cost of detection. In a recent paper, we have shown that an integrated optical Mach-Zehnder interferometer, a highly sensitive all-optical device made of a cheap photopolymer, can be used as a powerful lab-on-a-chip tool for specific, labelfree detection of proteins. By proper modifications of this technique, our interferometric biosensor was combined with a microfluidic system allowing the rapid and specific detection of bacteria from solutions, having the surface of the sensor functionalized by bacterium-specific antibodies. The experiments proved that the biosensor was able to detect Escherichia coli bacteria at concentrations of 106 cfu/ml within a few minutes, that makes our device an appropriate tool for fast, label-free detection of bacteria from body fluids such as urine or sputum. On the other hand, possible applications of the device may not be restricted to medical microbiology, since bacterial identification is an important task in microbial forensics, criminal investigations, bio-terrorism threats and in environmental studies, as well.

Refine search results

Surface plasmon resonance imaging biosensors for aromatase based on a potent inhibitor and a specific antibody: Sensor development and application for biological material

Design of an amperometric xanthine biosensor based on a graphite transducer patterned with noble metal microparticles

Rapid flow injection electrochemical detection of 3,3′,4,4′ tetrachlorobiphenyl using stabilized lipid membranes with incorporated sheep antibody

Enantioselective inhibition of immobilized acetylcholinesterase in biosensor determination of pesticides

Kinetic study of the decomposition of Prussian Blue electrocatalytic layer during cathodic reduction of hydrogen peroxide

Comparison of biosensors based on gold and nanocomposite electrodes for monitoring of malic acid in wine

Integrated optical biosensor for rapid detection of bacteria