TY - GEN A1 - Lange, Ulrich A1 - Hirsch, Thomas A1 - Mirsky, Vladimir M. A1 - Wolfbeis, Otto S. T1 - Hydrogen sensor based on graphene - palladium nanocomposite T2 - Electrochimica Acta N2 - A composite material was prepared from graphene and palladium nanoparticles (PdNP) by layer-by-layer deposition on gold electrodes. The material was characterized by absorption spectroscopy, scanning electron microscopy, Raman spectroscopy and surface plasmon resonance. Cyclic voltammetry demonstrated the presence of electrocatalytic centers in the palladium decorated graphene. This material can serve as a sensor material for hydrogen at levels from 0.5 to 1% in synthetic air. Pure graphene is poorly sensitive to hydrogen, but incorporation of PdNPs increases its sensitivity by more than an order of magnitude. The effects of hydrogen, nitrogen dioxide and humidity were studied. Sensor regeneration is accelerated in humid air. The sensitivity of the nanocomposite depends on the number of bilayers of graphene–PdNPs. KW - Graphene KW - Palladium KW - Nanoparticle KW - Sensor KW - Layer-by-layer Y1 - 2011 U6 - https://doi.org/10.1016/j.electacta.2010.10.078 SN - 0013-4686 VL - 56 IS - 10 SP - 3707 EP - 3712 ER - TY - GEN A1 - Wolpert, Benjamin A1 - Wolfbeis, Otto S. A1 - Mirsky, Vladimir M. T1 - Gas sensing properties of electrically conductive Cu(I) compounds at elevated temperatures T2 - Sensors and Actuators B: Chemical N2 - Changes in the electrical conductance at 240 °C of a number of copper(I) compounds including CuI, CuBr, Cu2Te, Cu12Sb4S13, (CuI)2P14, and of NiO were measured following the exposure to the gases ammonia, nitrogen dioxide, nitrous oxide, carbon monoxide, carbon dioxide, and propane. Analytical sensitivity and kinetic parameters were compared quantitatively. The high diversity of sensitivity patterns makes these compounds promising candidates for use in sensor arrays. Principal component analysis of the data obtained with a virtual sensor array enabled highly selective sensing of five of the six analytes studied using only two principle components. Activation energies of the charge transport in the materials were determined. KW - Gas sensor KW - Ammonia sensor KW - Conductometric sensor KW - Sensor array KW - Copper(I) KW - High-temperature sensing Y1 - 2009 U6 - https://doi.org/10.1016/j.snb.2009.04.042 SN - 0925-4005 VL - 142 IS - 2 SP - 446 EP - 450 ER - TY - GEN A1 - Delaney, Tetyana L. A1 - Zimin, Denys A1 - Rahm, Michael A1 - Weiss, Dieter A1 - Wolfbeis, Otto S. A1 - Mirsky, Vladimir M. T1 - Capacitive detection in ultrathin chemosensors prepared by molecularly imprinted grafting photopolymerization T2 - Analytical Chemistry N2 - The usual applications of capacitive detection in chemo- and biosensors are based on changes in effective thickness of insulating layers due to adsorption of analyte onto receptors. Ultrathin chemosensors based on molecularly imprinted polymerization enable a realization of another capacitive approach that exploits changes in electrical capacitance due to modification of the dielectric constant of the polymer. Such chemosensors were prepared by photografted molecularly imprinted polymerization on the surface of gold electrodes. An adsorbed layer of hydrophobic photoinitiator (benzophenone) provided grafted polymerization on the surface of the alkanethiol-modified gold electrode. The chemosensors were characterized by cyclic voltammetry, impedance spectroscopy, and scanning electron and atomic force microscopy. Binding of analyte was detected by measurements of electrical capacitance. The results indicate a decrease of the dielectric constant of the polymer layer due to analyte binding up to 20%. Y1 - 2007 U6 - https://doi.org/10.1021/ac062143v SN - 0003-2700 SN - 1520-6882 VL - 79 IS - 8 SP - 3220 EP - 3225 ER - TY - GEN A1 - Mirsky, Vladimir M. A1 - Kulikov, Valentin A1 - Wolfbeis, Otto S. T1 - Complete system for combinatorial synthesis and functional investigation of conductive polymers T2 - American Chemical Society PMSE Preprints N2 - Complete system for combinatorial electrochemical synthesis and functional characterization of combinatorial libraries formed by different polymers and polymeric structures will be presented. Control of electrical potential of single electrode groups consisting of four electrodes (designed for 4-point measurements ) on the array comprising 96 such electrode groups provides addressable electrochemical polymer synthesis on the defined electrodes. After polymerization, electrical characteristics of polymers or/and polymer/electrode contacts and influence of potential analytes on these characteristic are measured. Final data analysis provides complete analytically relevant information on the investigated thin polymer layers or multilayer polymer structures: absolute and relative sensitivity, response time, reversibility, reproducibility, regeneration kinetics, linearity or binding constant. Examples of applications for the development of gas-sensitive (co)polymers and optimization of their sensitive properties and polymer/metal contacts will be presented. Y1 - 2005 VL - 93 SP - 1053 ER - TY - GEN A1 - Hirsch, Thomas A1 - Zharnikov, Michael A1 - Shaporenko, Andrey A1 - Stahl, Joachim A1 - Weiss, Dieter A1 - Wolfbeis, Otto S. A1 - Mirsky, Vladimir M. T1 - Size-controlled electrochemical synthesis of metallic nanoparticles on molecular templates T2 - Angewandte Chemie International Edition N2 - Reduction on the spot: Planarly adsorbed thiolated porphyrin molecules (purple) incorporated in an insulating alkanethiol monolayer (blue) function as nanoelectrodes for the local reduction of metals (gray). This approach was applied for the in situ synthesis of nanoparticles of a predetermined size. Y1 - 2005 U6 - https://doi.org/10.1002/anie.200500912 SN - 1521-3773 VL - 44 IS - 41 SP - 6775 EP - 6778 ER - TY - GEN A1 - Zybin, Alexander A1 - Grunwald, Christian A1 - Mirsky, Vladimir M. A1 - Kuhlmann, Jürgen A1 - Wolfbeis, Otto S. A1 - Niemax, Kay T1 - Double-wavelength technique for surface plasmon resonance measurements: basic concept and applications for single sensors and two-dimensional sensor arrays T2 - Analytical Chemistry N2 - A new technique for on-line monitoring of analyte binding to sensor surfaces by surface plasmon resonance (SPR) detection is described. It is based on differential measurements using two wavelengths provided by two diode lasers. The technique is as simple and robust as the conventional SPR detection measuring the reflected radiation at fixed incidence angle, but it has the advantage of being nonsensitive to variations of the resonance width and providing essentially higher signal/noise ratios. The paper presents the first four channel prototype system for parallel 2D-monitoring at four different spots. One channel is always used as a reference to compensate temperature fluctuations and nonspecific adsorptions. Calibration with sucrose solutions revealed an absolute sensitivity of Δn ∼ 5 × 10-6. The new technique is tested with a biotin−streptavidin binding and with hybridization/denaturation of DNA. Biotin binding to a streptavidin monolayer is detected with a signal/noise ratio of about 5, which demonstrates the high potential of the new technique for applications in drug discovery. Applications to gene analysis are tested with short oligonucleotides of the sequences used for genotyping human hepatitis C viruses. A selective response to complementary oligonucleotides is observed. The high reproducibility in subsequent cycles of hybridization/denaturation (by formamide or by heating) points out potential applications of the technique in medical diagnostics, food industry, genomics, and proteomics too. Y1 - 2005 U6 - https://doi.org/10.1021/ac048156v SN - 0003-2700 SN - 1520-6882 VL - 77 IS - 8 SP - 2393 EP - 2399 ER - TY - CHAP A1 - Mirsky, Vladimir M. A1 - Kulikov, Valentin A1 - Hao, Qingli A1 - Wolfbeis, Otto S. T1 - Application of combinatorial electropolymerization to the development of chemical Sensors T2 - Combinatorial and artificial intelligence methods in materials science II, symposium held December 1 - 4, 2003, Boston, Massachusetts, U.S.A. N2 - Combinatorial electropolymerization with electrical addressing was realized on the array of 96 electrode groups, each from four electrodes. The polymer synthesis was combined with subsequent high-throughput investigation of analytical properties of synthesized polymers. Two-and four-point techniques were applied simultaneously to measure electrical properties of synthesized polymers and contact resistances between electrodes and polymers and modifications of these parameters on addition of analyte. The system was used for development of sensitive materials for detection of gaseous hydrogen chloride. Y1 - 2004 SN - 1-55899-742-3 U6 - https://doi.org/10.1557/PROC-804-JJ4.1 SP - 111 EP - 116 PB - Materials Research Society CY - Warrendale, Pa. ER - TY - GEN A1 - Samoylov, Anton V. A1 - Mirsky, Vladimir M. A1 - Hao, Qingli A1 - Swart, Claudia A1 - Shirshov, Yuri M. A1 - Wolfbeis, Otto S. T1 - Nanometer-thick SPR sensor for gaseous HCl T2 - Sensors and Actuators B: Chemical N2 - The optical properties of electrochemically polymerized N-methylaniline are changed in the presence of gaseous hydrogen chloride. This effect was used for preparation of chemical sensors with transduction based on surface plasmon resonance. The interaction of hydrogen chloride with a two nm layer of poly-(N-methylaniline) on gold leads to the shift of the surface plasmon resonance. The analysis of the resonance spectra demonstrates that the effect is caused by an increase of the imaginary component of the refractive index; a minor contribution is also provided by film condensation leading to an increase of the real component of the refractive index and a decrease in the thickness. The effect is selective and quasi-reversible. The concentration dependence of the gas effect obeys Langmuir's adsorption isotherm with a reciprocal value of the binding constant of 850 ± 160 ppm. KW - Gas sensor KW - HCI sensors KW - Surface plasmon resonance KW - Electropolymerization KW - Poly-(N-methyl-aniline) KW - Fire detector Y1 - 2005 U6 - https://doi.org/10.1016/j.snb.2004.08.029 SN - 0925-4005 VL - 106 IS - 1 SP - 369 EP - 372 ER - TY - GEN A1 - Zhi, Zheng-liang A1 - Drazan, Viktor A1 - Wolfbeis, Otto S. A1 - Mirsky, Vladimir M. T1 - Electrocatalytic activity of DNA on electrodes as an indication of hybridization T2 - Bioelectrochemistry N2 - Electron transfer between metal electrodes and ferro/ferricyanide is completely suppressed at low ionic concentration. We describe here a new phenomenon related to this reaction: an immobilisation of thiolated single-stranded DNA on gold electrodes retains this activity at low ionic strength up to the level corresponding to the high ionic strength. In contrast, a hybridisation of the complementary DNAwith the thiolated single-stranded DNA followed by a binding onto the electrodes, attenuated the electrocatalytic effect. These effects can be used for discrimination between single-stranded DNA and double-stranded DNA and for semi-quantitative measurement of complementary DNA in a sample. KW - DNA KW - DNA-sensor KW - Biosensor KW - Electrocatalysi KW - Hybridisation KW - Oligonucleotide KW - Gene analysis Y1 - 2006 U6 - https://doi.org/10.1016/j.bioelechem.2005.02.006 SN - 1567-5394 VL - 68 IS - 1 SP - 1 EP - 6 ER - TY - GEN A1 - Kulikov, Valentin A1 - Mirsky, Vladimir M. A1 - Delaney, Tetyana L. A1 - Donoval, Daniel A1 - Koch, Alexander W. A1 - Wolfbeis, Otto S. T1 - High-throughput analysis of bulk and contact conductance of polymer layers prepared by combinatorial electropolymerization T2 - Measurement Science and Technology N2 - An approach for high-throughput analysis of bulk and contact conductance of polymer layers is described and evaluated. The approach, based on s24-technique (simultaneous two- and four-point conductance measurements), was realized as a high-throughput method and applied for investigation of conductive polymers on an array of interdigital platinum electrodes. Several examples demonstrate distinctive influence of combinatorially varied conditions of polymer synthesis (polymerization charge, content of copolymers) as well as chemical treatment of the synthesized polymers in bulk and contact resistance of metal/polymer/metal systems. The developed high-throughput s24-technique can be widely applied to material research for investigation of bulk and contact electrical properties. Y1 - 2005 U6 - https://doi.org/10.1088/0957-0233/16/1/013 SN - 1361-6501 SN - 0957-0233 VL - 16 IS - 1 SP - 95 EP - 99 ER - TY - GEN A1 - Ando, Masanori A1 - Swart, Claudia A1 - Pringsheim, Erika A1 - Mirsky, Vladimir M. A1 - Wolfbeis, Otto S. T1 - Optical ozone sensing properties of poly(2-chloroaniline), poly(N-methylaniline) and polyaniline films T2 - Sensors and Actuators B: Chemical N2 - The ozone-sensitive visible/near-IR absorbance changes of poly(2-chloroaniline) (P(2ClANI)), poly(N-methylaniline) (P(NMeANI)) and polyaniline (PANI) films were investigated. These three polymer films, which were assumed to be present partially in a protonated form and partially in a reduced form, were prepared by chemical oxidation of the monomers followed by treatment with the reducing agent disodium disulfite. The P(2ClANI) film was sensitive to ozone at concentrations of down to 2.5 ppm, but saturation of sensitivity started to appear above 50 ppm. By contrast, the PANI and P(NMeANI) films were sensitive to ozone in a concentration range of 50–100 ppm without showing saturation of sensitivity. KW - Optical ozone sensing KW - Poly(2-chloroaniline) film KW - Poly(N-methylaniline) film KW - Polyaniline film KW - Visible/near-IR absorbance change Y1 - 2005 U6 - https://doi.org/10.1016/j.snb.2004.12.083 SN - 0925-4005 VL - 108 IS - 1-2 SP - 528 EP - 534 ER - TY - GEN A1 - Ando, Masanori A1 - Swart, Claudia A1 - Pringsheim, Erika A1 - Mirsky, Vladimir M. A1 - Wolfbeis, Otto S. T1 - Ozone sensing properties of polyaniline derivatives T2 - Chemical Sensors (Suppl. B) Y1 - 2004 VL - 20 SP - 534 EP - 535 ER - TY - GEN A1 - Prodramidis, Mamas I. A1 - Hirsch, Thomas A1 - Wolfbeis, Otto S. A1 - Mirsky, Vladimir M. T1 - Enantioselective chemosensors based on spreader-bar structures T2 - Electroanalysis N2 - Chiroselective binding sites have been created on thin gold films by application of the spreader-bar approach. Impedometric techniques and surface plasmon resonance were applied to detect binding. (R)-(+)-1,1 '-Binaphthyl-2,2 '-diol (R-BNOH) and (S)-(-)-1,1 '-binaphthyl-2,2'-diol (S-BNOH) were used as model analytes. The artificial receptors were prepared by co-adsorption of 16-mercaptohexadecane (matrix) with a thiol-modified chiral selector (template). The conjugates of d, l-thioctic acid and (R)-(+)- or (S)-(-)-1,1'-binaphthyl-2,2'-diamine were used as templates. Different concentration ratios of the matrix and template were tested. No chiral selectivity of surfaces formed by either the matrix or the template alone was observed. The use of alkylthiols shorter than 16-mercaptohexadecane led to the formation of surfaces with no chiral selectivity. The gold electrodes coated by the spreader-bar technique displayed an enantioselectivity of up to 4.76 or up to 2.55 as measured by the capacitive and SPR methods, espectively. KW - Enantioselective artificial receptors KW - Spreader-bar technique KW - Capacitive chemosensor KW - Surface plasmon resonance Y1 - 2003 U6 - https://doi.org/10.1002/elan.200302756 SN - 1521-4109 VL - 15 IS - 22 SP - 1795 EP - 1798 ER - TY - GEN A1 - Mirsky, Vladimir M. A1 - Kulikov, Valentin A1 - Hao, Qingli A1 - Wolfbeis, Otto S. T1 - Multiparameter High Throughput Characterization of Combinatorial Chemical Microarrays of Chemosensitive Polymers T2 - Macromolecular Rapid Communications N2 - High throughput characterization of combinatorial libraries demands a compromise between completeness of the study and reasonable investigation time. This compromise can be found by the development of test protocols consisting of the minimal number of the most informative measurements. Multiparameter high throughput characterization of sensitive materials is described. The parameters include response time, regeneration time, reversibility, reproducibility, sensitivity, linearity. The approach was applied for characterization of conductometric gas-sensitive polymer materials. Chemical microarrays prepared by electrochemical synthesis of polymers on platinum electrodes. Y1 - 2004 U6 - https://doi.org/10.1002/marc.200300210 SN - 1521-3927 VL - 25 IS - 1 SP - 253 EP - 258 ER - TY - GEN A1 - Hirsch, Thomas A1 - Kettenberger, Hubert A1 - Wolfbeis, Otto S. A1 - Mirsky, Vladimir M. T1 - A simple strategy for preparation of sensor arrays: Nanostructured monolayers as recognition elements T2 - Chemical Communications N2 - The spreader-bar approach is a simple method for producing a huge variety of receptors with different selectivities. A sensor-array consisting of five such receptors is presented. A pattern recognition provides selective detection of different purines and pyrimidines. Y1 - 2003 U6 - https://doi.org/10.1039/b210554c SN - 1359-7345 SN - 1364-548X IS - 3 SP - 432 EP - 433 ER - TY - GEN A1 - Panasyuk-Delaney, Tanya A1 - Mirsky, Vladimir M. A1 - Wolfbeis, Otto S. T1 - Capacitive sensors based on photografted molecularly imprinted polymers T2 - Biocybernetics and Biomedical Engineering N2 - The reversible chemosensors to creatinine and desmetryn based on artificial chemoreceptors are described. A grafted photopolymerization combined with a technique of molecular imprinting was used for the receptor layer preparation. After polymer deposition and intensive washing from templates, the electrodes were investigated by impedance spectrometry. Creatinine and desmetryn binding were detected as a decrease in the electrode capacitance. Sensor response to creatining was highly selective. No response to the addition of sodium chloride, creatine, urea or glucose were observed. The electrodes coated with the molecularly imprinted polymers selective to desmetryn displayed specific binding of this herbicide: only small capacitive effects were observed to addition of terbumeton or atrazine, while metribuzine displayed capacitance decrease similar to desmetryn. KW - capacitive sensor KW - creatinine KW - atrazine KW - chemical sensor KW - photografted polymerization Y1 - 2001 SN - 0208-5216 VL - 21 IS - 3 SP - 43 EP - 54 ER - TY - GEN A1 - Panasyuk-Delaney, Tanya A1 - Mirsky, Vladimir M. A1 - Ulbricht, Mathias A1 - Wolfbeis, Otto S. T1 - Impedometric herbicide chemosensors based on molecularly imprinted polymers T2 - Analytica Chimica Acta N2 - The technique of grafting polymerization has been used for preparation of thin films of molecularly imprinting polymers on the surface of polypropylene membranes and on hydrophobized gold electrodes. The herbicide desmetryn was used as a template. The solid supports used were hydrophobic, while the polymer was hydrophilic. The adsorbed layer of benzophenone, irradiated by UV-light, initiated a radical polymerization near the surface. Polymer films were characterized by weighing, contact angle measurements and impedance spectroscopy. The electrodes coated with the molecularly imprinted polymers displayed fairly specific binding of desmetryn, as detected by the decrease in the capacitance of the electrode. Only small capacitive effects were observed on addition of terbumeton or atrazine, while metribuzine displayed capacitance decrease similar to desmetryn. KW - Molecular imprinting KW - Capacitive sensor KW - Chemical sensor KW - Grafting polymerization KW - Photopolymerization Y1 - 2001 U6 - https://doi.org/10.1016/S0003-2670(00)01280-0 SN - 0003-2670 VL - 435 IS - 1 SP - 157 EP - 162 ER - TY - CHAP A1 - Wrobel, Nadia A1 - Riepl, Michael A1 - Schinkinger, Manfred A1 - Mirsky, Vladimir M. A1 - Wolfbeis, Otto S. T1 - Capacitive thin film biosensors for bacteriophages and nucleic acids T2 - Proceedings, EMBEC ’99, November 4 - 7, 1999, Vienna, Austria Y1 - 1999 SP - 362 EP - 363 PB - IFMBE CY - Stevenage ER - TY - GEN A1 - Panasyuk-Delaney, Tanya A1 - Mirsky, Vladimir M. A1 - Piletsky, Sergey A. A1 - Wolfbeis, Otto S. T1 - Electropolymerized molecularly imprinted polymers as receptor layers in capacitive chemical sensors T2 - Analytical Chemistry N2 - The first application of molecularly imprinted polymers to chemical sensors with capacitive detection is described. The sensitive layer was prepared by electropolymerization of phenol on gold electrodes in the presence of the template (phenylalanine). The insulating properties of the polymer layer were studied by electrochemical impedance spectroscopy. Electrical leakages through the polymer layer were suppressed by deposition of a self-assembled monolayer of mercaptophenol before polymerization and of alkanethiol after polymerization. At the final stage of sensor preparation, the template was removed. The multilayer system obtained displayed a decrease in electrical capacitance on addition of phenylalanine. Only a low response was observed toward other amino acids and phenol. Y1 - 1999 U6 - https://doi.org/10.1021/ac9903196 SN - 0003-2700 SN - 1520-6882 VL - 71 IS - 20 SP - 4609 EP - 4613 ER - TY - GEN A1 - Bajari, Tarek M. A1 - Lindstedt, Ken A. A1 - Riepl, Michael A1 - Mirsky, Vladimir M. A1 - Nimpf, Johannes A1 - Wolfbeis, Otto S. A1 - Dresel, Hans A. A1 - Bautz, Ekkehard K. F. A1 - Schneider, Wolfgang Johann T1 - A minimal binding domain of the low density lipoprotein receptor gene family T2 - Biological Chemistry KW - Ligand binding KW - Low density lipoprotein KW - Phage display KW - Receptor KW - Oocyte Y1 - 1998 U6 - https://doi.org/10.1515/bchm.1998.379.8-9.1053 SN - 1437-4315 VL - 379 IS - 8-9 SP - 1053 EP - 1062 ER - TY - CHAP A1 - Mirsky, Vladimir M. A1 - Riepl, Michael A1 - Mass, Markus A1 - Hirsch, T. A1 - Schweiss, R. A1 - Wolfbeis, Otto S. ED - Vincenzini, Pietro ED - Dori, L. T1 - Capacitive detection of analyte binding in thin film chemo- and biosensors T2 - Solid State Chemical and Biochemical Sensors Y1 - 1999 SN - 88-86538-27-8 SP - 441 EP - 448 PB - Techna CY - Faenza ER - TY - GEN A1 - Mirsky, Vladimir M. A1 - Mass, Markus A1 - Krause, Christian A1 - Wolfbeis, Otto S. T1 - Capacitive approach to determine phospholipase A2 activity towards artificial and natural substrates T2 - Analytical Chemistry N2 - A capacitive approach has been employed to develop a novel method to determine phospholipase activity. The sensing electrodes have a structure like Au/S(CH₂)₁₇CH₃/substrate/electrolyte. Hydrolysis of the substrate, mediated by phospholipase A₂, leads to the formation of water-soluble products from the insoluble substrate. This results in desorption of these products into aqueous phase and corresponding increase of the electrode capacitance. The requirement of high water solubility of the reaction products can be achieved in two ways. In the first, short-chain phospholipids are used as the substrate, in which case, water-soluble products are formed and no additional reagents are required to promote desorption of these products. The sensors prepared by this strategy provide sensitive qualitative detection of phospholipases. The second way is based on the use of a water-soluble acceptor (for example, β-cyclodextrin) to solubilize the products of hydrolysis. It allows semiquantitative detection of phospholipase activity toward long-chain natural substrates. The reaction kinetics for this case was found to be monoexponential and linearly dependent on the phospholipase concentration. The detection limit of this method, as tested with phospholipase A₂ from bee venom and soy bean lecithin as the substrate, is ∼0.5 ng/mL (500 μunits/mL). Y1 - 1998 U6 - https://doi.org/10.1021/ac980102w SN - 0003-2700 SN - 1520-6882 VL - 70 IS - 17 SP - 3674 EP - 3678 ER - TY - GEN A1 - Mirsky, Vladimir M. A1 - Riepl, Michael A1 - Wolfbeis, Otto S. T1 - Capacitive monitoring of protein immobilization and antigen-antibody reaction on the monomolecular films of alkylthiols adsorbed on gold electrodes T2 - Biosensors and Bioelectronics N2 - Self-assembled monolayers of omega-mercaptohexadecanoic acid and omega-mercaptohexadecylamine on gold electrodes are stable at neutral pH and display pure capacitive behavior at frequencies around 20 Hz. Different methods of covalent immobilization of proteins on these monolayers are compared. Various reagents including succinimides, thionylchloride, p-nitrophenol and carbodiimides were used to activate the carboxy groups of the adsorbed monolayer of omega-mercaptohexadecanoic acid. Glutaraldehyde, cyanuric chloride and phenylene diisocyanate were used to activate the amino groups of the monolayer of omega-mercaptohexadecylamine. The immobilization of albumin on the activated surface was studied by capacitive measurements. The N-hydroxysuccinimide and carbodiimide methods were identified as most suitable for protein immobilization in that they did not compromise the insulating properties of the alkylthiol layer and led to maximal increase of its dielectric thickness. These approaches were used for a layer-by-layer preparation of a capacitive immunosensor. Specifically, antibodies to human serum albumin were immobilized on the alkylthiol mono-layer. Binding of the antigen led to a decrease of the electrode capacitance. The detection limit of the immunosensor is as low as 15 nM (1 mg/l). Y1 - 1997 U6 - https://doi.org/10.1016/S0956-5663(97)00053-5 SN - 0956-5663 VL - 12 IS - 9-10 SP - 977 EP - 989 ER - TY - GEN A1 - Mirsky, Vladimir M. A1 - Hirsch, Thomas A1 - Panasyuk, Tatiana L. A1 - Piletsky, Sergey A. A1 - Wolfbeis, Otto S. T1 - Two- and three-dimensional artificial chemoreceptors: molecular spreader-bar vs. molecular imprinting T2 - Medical and Biological Engineering and Computing Y1 - 1999 SN - 0140-0118 SN - 1741-0444 VL - 37 IS - suppl.2 SP - 344 EP - 345 ER - TY - GEN A1 - Mirsky, Vladimir M. A1 - Hirsch, Thomas A1 - Piletsky, Sergey A. A1 - Wolfbeis, Otto S. T1 - A spreader-bar approach to molecular architecture: formation of stable artificial chemoreceptors T2 - Angewandte Chemie International Edition N2 - The destructive influence of lateral diffusion on nanostructured monolayers can be prevented by using the spreader-bar technique. This approach allows the formation of stable artificial receptors for barbituric acid by lateral structuring of a dodecanethiol monolayer with molecular spreader-bars from thiobarbituric acid without chemical polymerization (see schematic representation). The new technique may have applications in chemosensors, affinity chromatography, stereoselective catalysis, and molecular electronics. KW - Molecular architecture KW - Molecular recognition KW - Monolayers KW - Nanostructures KW - Sensors Y1 - 1999 U6 - https://doi.org/10.1002/(SICI)1521-3773(19990419)38:8<1108::AID-ANIE1108>3.0.CO;2-C SN - 1521-3773 VL - 38 IS - 8 SP - 1108 EP - 1110 ER - TY - GEN A1 - Riepl, Michael A1 - Mirsky, Vladimir M. A1 - Novotny, Ivan A1 - Tvarozek, Vladimir A1 - Rehacek, Vlastimil A1 - Wolfbeis, Otto S. T1 - Optimization of capacitive affinity sensors: drift suppression and signal amplification T2 - Analytica Chimica Acta N2 - The detection limit of capacitive affinity sensors based on the gold–alkanethiol system can be improved by optimization of sensor preparation and by signal amplification. The dissociation of the gold–sulfur binding is often a critical point leading to operative errors of such sensors. The stability of self-assembled monolayers prepared with different thiols on gold electrodes in aqueous and organic solvents was studied by the capacitive technique. The results show that monolayers made of 16-mercaptohexadecanoic acid are stable in aqueous solution and can be hardly extracted from a gold surface by ethanol, methanol, or dioxane, while a considerable damage of self-assembled monolayers was observed due to incubation in chloroform or dimethylformamide. In contrast, self-assembled monolayers made from short-chain disulfides or thiols (such as 3,3′-dithio-bis(propionic acid N-hydroxysuccinimide ester) or 11-mercaptoundecanoic acid) displayed a poor stability in aqueous phase. Capacitive affinity sensors based on these short-chain thiols showed a considerable drift of the signal. The use of long-chain thiols resulted in a stable signal; it was applied to compare capacitive effects due to immobilization of different biological molecules and for preparation of different biosensors. The response of capacitive biosensors can be amplified by formation of a sandwich structure. This principle was illustrated by subsequent adsorption of polyclonal anti-HSA after binding of HSA with a sensor for HSA based on monoclonal antibodies. KW - Affinity sensor KW - Self-assembly KW - Capacitive sensor KW - Signal amplification KW - Immunosensor KW - Biosensor Y1 - 1999 U6 - https://doi.org/10.1016/S0003-2670(99)00195-6 SN - 0003-2670 VL - 392 IS - 1 SP - 77 EP - 84 ER - TY - GEN A1 - Riepl, Michael A1 - Mirsky, Vladimir M. A1 - Wolfbeis, Otto S. T1 - Electrical control of alkanethiols self-assembly on a gold surface as an approach for preparation of microelectrode arrays T2 - Microchimica Acta N2 - It is shown by capacitive monitoring that the self-assembly of alkanethiols on gold electrodes and desorption of these self-assembled monolayers from the electrodes are controlled by the electrode potential. At neutral pH, chemical adsorption of alkanethiols was observed at an electrode potential of +300 mV vs SCE, but only physical adsorption was detected when the electrode potential was −1400 mV vs SCE. At electrode potentials between these values (−300 mV, −600 mV), chemical adsorption of alkanethiols occurred, but the alkanethiol monolayers were not stable in the absence of the alkanethiol in the bulk solution and were desorbed from the gold electrode. The desorption rate was higher at more negative electrode potentials. These results can be used in designing methods for electrically addressable immobilization of different receptors on (micro)electrode arrays. This has been demonstrated by deposition of two different types of alkanethiols onto a two-electrode array. KW - self-assembly KW - electrical control KW - electrode capacitance KW - addressable immobilization KW - (bio)sensor array Y1 - 1999 U6 - https://doi.org/10.1007/s006040050006 SN - 0026-3672 SN - 1436-5073 VL - 131 IS - 1 SP - 29 EP - 34 ER - TY - GEN A1 - Schweiß, Rüdiger A1 - Mirsky, Vladimir M. A1 - Wolfbeis, Otto S. T1 - Capacitive study of self-assembled alkylthiol monolayers: surface charge effects and kinetics of surfactants adsorption T2 - Materials Science Forum Y1 - 1998 U6 - https://doi.org/10.4028/www.scientific.net/MSF.287-288.427 SN - 1662-9752 SN - 0255-5476 VL - 287-288 SP - 427 EP - 430 ER - TY - GEN A1 - Ando, Masanori A1 - Swart, Claudia A1 - Pringsheim, Erika A1 - Mirsky, Vladimir M. A1 - Wolfbeis, Otto S. T1 - Optical ozone detection by use of polyaniline film T2 - Solid State Ionics N2 - We report on the optical ozone sensitivity of a polyaniline (PANI) film prepared on the inner wall of a polystyrene cuvette by chemical oxidation of aniline from aqueous solution. The PANI film showed changes of optical absorbance in the presence of 50–100 ppm ozone in air at room temperature. The absorbance change was largest at wavelengths in the range of 500–800 nm. The absorbance changes brought about by ozone was partially reversible after removal of ozone from the atmosphere. These results suggest that PANI is a potential material for optical ozone detection. KW - Optical ozone detection KW - Polyaniline film KW - Visible near-IR absorption Y1 - 2002 U6 - https://doi.org/10.1016/S0167-2738(02)00338-7 SN - 0167-2738 VL - 152-153 SP - 819 EP - 822 ER - TY - GEN A1 - Panasyuk-Delaney, Tanya A1 - Mirsky, Vladimir M. A1 - Wolfbeis, Otto S. T1 - Capacitive creatinine sensor based on molecularly imprinted polymer T2 - Electroanalysis N2 - The first reversible chemosensor to creatinine based on artificial chemoreceptors is described. The receptor layer was prepared by molecularly imprinted photopolymerization of acrylamidomethylpropanesulfonic acid and methylenediacrylamide. The polymer layer was grafted onto the surface of gold electrodes coated with an alkanethiol monolayer. Creatinine binding was detected by a decrease in the electrode capacitance. The sensor response is reversible and highly selective: no response to addition of sodium chloride, creatine, urea or glucose were observed. The detection limit for creatinine is 10 μM which is optimal for medical applications. KW - Capacitive sensor KW - Creatinine KW - Molecularly imprinted polymer KW - Chemical sensor KW - Photografted polymerization Y1 - 2002 U6 - https://doi.org/10.1002/1521-4109(200202)14:3<221::AID-ELAN221>3.0.CO;2-Y SN - 1521-4109 VL - 14 IS - 3 SP - 221 EP - 224 ER - TY - GEN A1 - Mirsky, Vladimir M. A1 - Vasjari, Majlinda A1 - Novotny, Ivan A1 - Rehacek, Vlastimil A1 - Tvarozek, Vladimir A1 - Wolfbeis, Otto S. T1 - Self-assembled monolayers as selective filters for chemical sensors T2 - Nanotechnology N2 - The lateral electrical conductivity of gold layers with thickness in the nanometre range was found to decrease due to adsorption of mercury, water, iodine and sulphuric compounds onto the gold surface. A self-assembled monolayer of hexadecanethiol, deposited on the gold surface, blocked the effects of water and volatile sulphuric compounds on the lateral conductivity of the gold layers, but does not block the effects of iodine and mercury. The results indicate a selective permeability of hexadecanethiol monolayers for mercury vapour, thus providing a method for development of ultrathin filters for chemical sensors. Y1 - 2002 SN - 0957-4484 VL - 13 IS - 2 SP - 175 EP - 178 ER - TY - CHAP A1 - Wu, Meng A1 - Lin, Zhihong A1 - Mirsky, Vladimir M. A1 - Wolfbeis, Otto S. ED - Zhou, Yikai T1 - Detection of DNA hybridization with surface plasmon resonance biosensor: comparison of immobilization of oligonucleotides by ssDNA and dsDNA T2 - Proceedings, International Conference on Sensor Technology (ISTC 2001), 10 - 12 October 2001, Wuhan, China N2 - In this research, a surface-plasmon resonance biosensor for nucleic acid detection was constructed, optimized and characterized. The kinetic response on hybridization was also studied. The biosensor was use as a platform for the study of the surface coverage control by single-strand or double-strand oligonucleotide immobilization. The dsDNA immobilization and offers a new way to surface coverage control for the nucleic acid biosensor construction. Y1 - 2001 SN - 0-8194-4119-8 U6 - https://doi.org/10.1117/12.440180 SP - 23 EP - 26 PB - SPIE CY - Bellingham, Wash. ER - TY - GEN A1 - Mirsky, Vladimir M. A1 - Panasyuk-Delaney, Tanya A1 - Wolfbeis, Otto S. T1 - Chemical sensors based on ultrathin membranes from molecularly imprinted polymers T2 - Membrane & cell biology Y1 - 2001 VL - 18 IS - 6 SP - 496 EP - 501 ER - TY - CHAP A1 - Lin, Zhihong A1 - Wu, Meng A1 - Ren, Shu A1 - Arbter, Michaela A1 - Boehmer, Martin A1 - Mirsky, Vladimir M. A1 - Wolfbeis, Otto S. ED - Zhou, Yikai T1 - Study of single and dual NIR fluorescently labeled nucleic acid conjugates for nucleic acid detection T2 - Proceedings, International Conference on Sensor Technology (ISTC 2001), 10 - 12 October 2001, Wuhan, China N2 - In this research, a near-IR fluorescent labeled nucleic acid conjugate for the nucleic acid detection was synthesized, and characterized preliminarily for the detection of the nucleic acid. Th conjugate combines the molecular recognition properties of the oligonucleotides with the near-IR fluorescence label PR646. Both single- and dual- labeled conjugates were studied for their hybridization with the complementary nucleic acid. The dual labeled conjugate has indicated that the self-quenching effect exists in ssDNA form while the fluorescence increases greatly after hybridization with the complementary nucleic acids. The time-resolved fluorescence was also studied. KW - Near infrared KW - luminescence Y1 - 2001 SN - 0-8194-4119-8 U6 - https://doi.org/10.1117/12.440165 SP - 111 EP - 114 PB - SPIE CY - Bellingham, Wash. ER - TY - GEN A1 - Mirsky, Vladimir M. A1 - Riepl, Michael A1 - Krause, Christian A1 - Novotny, Ivan A1 - Splonskowski, Markus A1 - Rehacek, Vlastimil A1 - Tvarozek, Vladimir A1 - Hummel, Helmut A1 - Wolfbeis, Otto S. T1 - Thin film electrodes for capacitive chemo- and biosensors: an optimization of the electrodes geometry T2 - Materials Science Forum KW - Biosensor KW - Capacitance KW - Chemical Sensors KW - Electrode Y1 - 1998 U6 - https://doi.org/10.4028/www.scientific.net/MSF.287-288.423 SN - 1662-9752 VL - 287-288 SP - 423 EP - 426 ER - TY - GEN A1 - Mirsky, Vladimir M. A1 - Wrobel, Nadia A1 - Riepl, Michael A1 - Hirsch, Thomas A1 - Wolfbeis, Otto S. T1 - Intelligente Nanostrukturen für Biosensoren und Sensor-Arrays T2 - BioTec: Zeitschrift für Biotechnologie Y1 - 1999 SN - 0937-2725 VL - 10 SP - 28 EP - 32 ER - TY - PAT A1 - Wolfbeis, Otto S. A1 - Mirsky, Vladimir M. A1 - Riepl, Michael T1 - Method for producing laterally organized structures on supporting surfaces Y1 - 2002 ER - TY - GEN A1 - Rehacek, Vlastimil A1 - Novotny, Ivan A1 - Tvarozek, Vladimir A1 - Riepl, Michael A1 - Hirsch, T. A1 - Mass, Markus A1 - Schweiss, R. A1 - Mirsky, Vladimir M. A1 - Wolfbeis, Otto S. ED - Breza, Jura ED - Donoval, Daniel T1 - Capacitive detection in thin film chemical sensors and biosensors T2 - Advanced Semiconductor Devices and Microsystems N2 - Thin film electrode chips on silicon substrate have been realized and utilized in development of different chemo- and biosensors. These affinity sensors are based on capacitive transducing and their general structure is thin film Au/alkanethiol/receptor. Several applications of thin film gold electrodes in capacitive sensors are presented. Y1 - 1998 SN - 0-7803-4909-1 SP - 255 EP - 258 PB - IEEE CY - Piscataway, NJ ER - TY - PAT A1 - Ando, Masanori A1 - Wolfbeis, Otto S. A1 - Mirsky, Vladimir M. T1 - Ozone detecting material and method for detecting ozone Y1 - 2002 ER -