An electrochemical biosensor is presented that directly reflects the metabolic activity of prokaryotic and eukaryotic cells. This biosensor can be used measure the biological activity of bacteria, yeasts and mammalian cells. This makes the sensor interesting for various applications in industry and science. A possible application is bioprocess control, monitor activities from yeasts, bacteria and fungi to increase the yield. Other applications are starter culture quality studies in the food industry and cytoxicological evaluation with mammalian cells. Our latest investigations additionally indicate the applicability of the electrochemical biosensor to measure algae and cyanobacteria. In our investigations, we were able to show that it was also possible to detect photosynthetic organisms with the electrochemical measurement method, used for investigations on prokaryotic and eukaryotic organisms before. Therefore, this the present study demonstrates an alternative to using this electrochemical biosensor equipped with alga and cyanobacteria for toxicological investigations based on selected test chemicals. The results of this study show a good correlation with those from reference methods, such as the Algal Growth Inhibition Test and the Microtox Test. The advantages of the new electrochemical biosensor are easy handling and shorter measurement time by using different types of test organisms. The evaluation of the sensor signal is based on the current-time curves of a potentiostatic measurement produced by the detection of microbially reduced mediator molecules immobilized in a gel structure. The mediator molecules are reduced during the measurement process. The reduced mediator molecules produce a current signal, which rapidly provides information about the vigor and vitality of living bacteria, yeasts, fungi or cells.

• Klíčová slova
• Algae, Biosensor, Cyanobacteria, Electrochemical, Mediator, Toxicity test,
• MeSH
• biosenzitivní techniky * metody   MeSH
• elektrochemické techniky metody   MeSH
• sinice * metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH

Interferon gamma (IFNγ) is a cytokine and an immunochemical marker that can be used for revealing of infectious diseases and especially for distinguishing of viral and some types of bacterial infections. Blood tests for IFNγ are typically based on immunoassays like Enzyme-Linked Immunosorbent Assay (ELISA). In this paper, a biosensor working on the principle of quartz crystal microbalance (QCM) was developed as an alternative to the standard analytical methods for IFNγ. The biosensor contained antibodies against IFNγ immobilized on QCM and also on gold nanoparticles. A sandwich containing QCM, gold nanoparticles and IFNγ was formed and formation of the sandwich caused decrease of oscillation frequency. The assay exerted limit of detection 5.7 pg/ml for a sample sized 50 μl and one measuring cycle was finished within 90 min. The assay by biosensor fully correlated to standard ELISA. In a conclusion, the biosensor appears to be a fully applicable analytical tool for a simple assay of IFNγ. Overall simplicity and no special requirement on staff and equipment are the major advantages of the here presented assay.

• Klíčová slova
• Bioassay, Biosensor, Cytokine, Diagnosis, ELISA, Immunoassay, Immunosensor, Infection, Lymphocyte, Macrophage, Virus,
• MeSH
• biosenzitivní techniky * MeSH
• imunoanalýza MeSH
• interferon gama MeSH
• kovové nanočástice * MeSH
• křemen MeSH
• lidé MeSH
• mikrorovnovážné techniky křemenného krystalu MeSH
• zlato MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• interferon gama MeSH
• křemen MeSH
• zlato MeSH

Cholinesterase inhibitors are widely used as pesticides in agriculture, but also form a group of organophosphates known as nerve chemical warfare agents. This calls for close attention regarding their detection, including the use of various biosensors. One such biosensor made in the Czech Republic is the Detehit, which is based on a cholinesterase reaction that is assessed using a colour indicator-the Ellman's reagent-which is anchored on cellulose filter paper together with the substrate. With the use of this biosensor, detection is simple, quick, and sensitive. However, its disadvantage is that a less pronounced yellow discoloration occurs, especially under difficult light conditions. As a possible solution, a new indicator/substrate carrier has been designed. It is made of glass nanofibres, so the physical characteristics of the carrier positively influence reaction conditions, and as a result improve the colour response of the biosensor. The authors present and discuss some of the results of the study of this carrier under various experimental conditions. These findings have been used for the development of a modified Detehit biosensor.

• Klíčová slova
• Ellman’s reagent, biosensor, cellulose filter paper, cholinesterase reaction, glass fibre filter paper,
• MeSH
• biosenzitivní techniky metody   MeSH
• cholinesterasové inhibitory chemie   MeSH
• nanovlákna chemie   MeSH
• sklo chemie   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• cholinesterasové inhibitory MeSH

Bisphenol A (BpA) is a chemical that is extensively used in common plastic products, such as food and drink containers. It can leach from the plastics and penetrate into the human body, where it acts as an endocrine disruptor with significant risks to human health. In order to minimize the exposure of human populations to BpA, methods for the detection of BpA are needed. In this work, we present a novel surface plasmon resonance (SPR) biosensor for ultrasensitive detection of BpA. Our approach combines a binding inhibition assay with functionalized gold nanoparticles for the enhancement of sensor response. We demonstrate that the developed biosensor enables the detection of BpA in a wide range of concentrations (0.01 to 100,000 ng/mL) with an extremely low limit of detection-5.2 pg/mL.

• Klíčová slova
• Binding inhibition assay, Bisphenol A, Functionalized gold nanoparticles, Surface plasmon resonance biosensor,
• MeSH
• benzhydrylové sloučeniny analýza   MeSH
• biosenzitivní techniky * MeSH
• fenoly analýza   MeSH
• kovové nanočástice chemie   MeSH
• limita detekce MeSH
• povrchová plasmonová rezonance přístrojové vybavení   MeSH
• reprodukovatelnost výsledků MeSH
• zlato chemie   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• benzhydrylové sloučeniny MeSH
• bisphenol A MeSH Prohlížeč
• fenoly MeSH
• zlato MeSH

An advanced optical biosensor was developed based on the enzymatic reaction with halogenated aliphatic hydrocarbons that is accompanied by the fluorescence change of pH indicator. The device is applicable for the detection of halogenated contaminants in water samples with pH ranging from 4 to 10 and temperature ranging from 5 to 60°C. Main advantages of the developed biosensor are small size (60×30×190mm(3)) and portability, which together with short measurement time of 1min belong to crucial attributes of analytical technique useful for routine environmental monitoring. The biosensor was successfully applied for the detection of several important halogenated pollutants under laboratory conditions, e.g., 1,2-dichloroethane, 1,2,3-trichloropropane and γ-hexachlorocyclohexane, with the limits of detection of 2.7, 1.4 and 12.1mgL(-1), respectively. The continuous monitoring was demonstrated by repetitive injection of halogenated compound into measurement solution. Consequently, field trials under environmental settings were performed. The presence of 1,2-dichloroethane (10mgL(-1)) was proved unambiguously on one of three potentially contaminated sites in Czech Republic, and the same contaminant was monitored on contaminated locality in Serbia. Equipped by Global Positioning System, the biosensor was used for creation of a precise map of contamination. Concentrations determined by biosensor and by gas chromatograph coupled with mass spectrometer exhibited the correlation coefficient of 0.92, providing a good confidence for the routine use of the biosensor system in both field screening and monitoring.

• Klíčová slova
• Dehydrochlorinase, Environmental monitoring, Field-testing, Haloalkane dehalogenase, Halogenated pollutant, Optical biosensor,
• MeSH
• Bacteria enzymologie   MeSH
• biosenzitivní techniky přístrojové vybavení   MeSH
• chemické látky znečišťující vodu analýza   metabolismus   MeSH
• chlorované uhlovodíky analýza   metabolismus   MeSH
• fluorescence MeSH
• fluorescenční spektrometrie přístrojové vybavení   MeSH
• hydrolasy metabolismus   MeSH
• monitorování životního prostředí přístrojové vybavení   MeSH
• voda analýza   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• chemické látky znečišťující vodu MeSH
• chlorované uhlovodíky MeSH
• haloalkane dehalogenase MeSH Prohlížeč
• hydrolasy MeSH
• voda MeSH

Colorimetric biosensors of cholinesterase inhibitors are ideal for fast, reliable, and very simple detection of agents in air, in water, and on surfaces. This paper describes an innovation of the Czech Detehit biosensor, which is based on a biochemical enzymatic reaction visualized by using Ellman's reagent as a chromogenic indicator. The modification basically consists of a much more distinct color response of the biosensor, attained through optimization of the reaction system by using Guinea Green B as the indicator. The performance of the modified biosensor was verified on the chemical warfare agents (sarin, soman, cyclosarin, and VX) in water. The detection limits ascertained visually (with the naked eye) were about 0.001 µg/mL in water (exposure time 60 s, inhibition efficiency 25%).

• Klíčová slova
• Guinea Green B, biosensor of cholinesterase inhibitors, chemical warfare agents, enzymatic reaction, visual evaluation,
• MeSH
• biosenzitivní techniky metody   MeSH
• chemické bojové látky analýza   MeSH
• cholinesterasové inhibitory analýza   MeSH
• kolorimetrie metody   MeSH
• lissaminová zelená barviva chemie   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• chemické bojové látky MeSH
• cholinesterasové inhibitory MeSH
• guinea green B MeSH Prohlížeč
• lissaminová zelená barviva MeSH

Contamination of surface water and drinking water with pharmaceuticals presents an environmental concern. It has been shown to affect aquatic organisms and have adverse health effects on humans. One of the most common pharmaceutical contaminants is the opioid analgesic tramadol. In this communication, we report on the first surface plasmon resonance biosensor-based detection of tramadol in water. The biosensor utilizes a binding inhibition format and enables detection of tramadol at a wide range of concentrations (5 orders of magnitude) with a limit of detection of 0.52 µg/L. The results of a small-scale environmental study are reported in which the biosensor was used to analyze river water samples. The results were found to agree well with those obtained using the liquid chromatography-tandem mass spectrometry (HPLC-MS/MS).

• Klíčová slova
• Biosensor, Surface plasmon resonance, Tramadol, Water quality monitoring,
• MeSH
• biosenzitivní techniky * metody   MeSH
• chemické látky znečišťující vodu * analýza   MeSH
• limita detekce MeSH
• monitorování životního prostředí * metody   MeSH
• opioidní analgetika * analýza   MeSH
• povrchová plasmonová rezonance * metody   MeSH
• řeky chemie   MeSH
• tandemová hmotnostní spektrometrie MeSH
• tramadol * analýza   MeSH
• vysokoúčinná kapalinová chromatografie MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• chemické látky znečišťující vodu * MeSH
• opioidní analgetika * MeSH
• tramadol * MeSH

Biosensors using cholinesterases as the biorecognition component have been used to assay organophosphates and carbamates for a long time. In this review, some strategies convenient for biosensor construction are presented. Solutions for cholinesterase immobilization and output signal monitoring are presented as the basic presumptions for successful biosensor construction.

• MeSH
• biosenzitivní techniky metody   MeSH
• cholinesterasy metabolismus   MeSH
• enzymy imobilizované metabolismus   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH
• Názvy látek
• cholinesterasy MeSH
• enzymy imobilizované MeSH

Steroid hormones as a class of emerging organic pollutant and high concern, due to their potential risks for human and environmental. Accurate analytical methods of steroid hormones are necessary in quantifying and monitoring. Biosensor is a promising technique. In this study, though part of 3α-HSD DNA to construct a regulatory plasmid and with the EGFP reporter gene to generate a reporter plasmid. Separately transformed into Escherichia coli strain BL21 and extracted the cell lysates as novel biosensor reagents. Analyzed the total amounts of steroid hormones in water, sediment, and soil samples using biosensor reagents, and compared these results with those obtained by HPLC. In summary, detection method using an EGFP reporter that can detect trace amounts of steroid hormones to reached fg/L. The optimal reaction time range and temperature were 30 min and 30 °C, respectively, while the most suitable organic solvent for the steroid hormone was 100% ethanol, up to 96-well plate format. This method is very suitable for high-throughput detection of environmental steroid hormone pollutants.

• Klíčová slova
• EGFP-Tagged, Fluorescent biosensor, Sediment, Soil, Steroid hormone, Water,
• MeSH
• biosenzitivní techniky * metody   MeSH
• DNA MeSH
• Escherichia coli genetika   MeSH
• ethanol MeSH
• hormony MeSH
• indikátory a reagencie MeSH
• látky znečišťující životní prostředí * MeSH
• lidé MeSH
• půda MeSH
• rozpouštědla MeSH
• steroidy MeSH
• voda MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• DNA MeSH
• ethanol MeSH
• hormony MeSH
• indikátory a reagencie MeSH
• látky znečišťující životní prostředí * MeSH
• půda MeSH
• rozpouštědla MeSH
• steroidy MeSH
• voda MeSH

A simple electrochemical DNA biosensor based on a glassy carbon electrode (GCE) was prepared by adsorbing double-stranded DNA (dsDNA) onto the GCE surface and subsequently used for the detection of dsDNA damage induced by hydroxyl radicals. Investigation of the mutual interaction between hydroxyl radicals and dsDNA was conducted using a combination of several electrochemical detection techniques: square-wave voltammetry for direct monitoring the oxidation of dsDNA bases, and cyclic voltammetry and electrochemical impedance spectroscopy as indirect electrochemical methods making use of the redox-active indicator [Fe(CN)6]4-/3-. Hydroxyl radicals were generated electrochemically on the surface of a boron-doped diamond electrode and chemically (via the Fenton's reaction or the auto-oxidation of Fe(II)). The extent of dsDNA damage by electrochemically generated hydroxyl radicals depended on the current density applied to the generating electrode: by applying 5, 10, and 50mAcm-2, selected relative biosensor responses decreased after 3min incubation from 100% to 38%, 27%, and 3%, respectively. Chemically generated hydroxyl radicals caused less pronounced dsDNA damage, and their damaging activity depended on the form of Fe(II) ions: decreases to 49% (Fenton's reaction; Fe(II) complexed with EDTA) and 33% (auto-oxidation of Fe(II); Fe(II) complexed with dsDNA) were observed after 10min incubation.

• Klíčová slova
• Auto-oxidation, Boron-doped diamond electrode, Electrochemical DNA biosensor, Fenton's reaction, Glassy carbon electrode, Hydroxyl radicals,
• MeSH
• adsorpce MeSH
• biosenzitivní techniky přístrojové vybavení   metody   MeSH
• DNA chemie   genetika   MeSH
• elektrochemie MeSH
• elektrody MeSH
• hydroxylový radikál farmakologie   MeSH
• peroxid vodíku chemie   MeSH
• poškození DNA * MeSH
• sklo chemie   MeSH
• uhlík chemie   MeSH
• železo chemie   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• DNA MeSH
• Fenton's reagent MeSH Prohlížeč
• hydroxylový radikál MeSH
• peroxid vodíku MeSH
• uhlík MeSH
• železo MeSH