@article{KramerHalamkovaPoghossianetal.2013,
  author    = {Kramer, Friederike and Halamkova, Lenka and Poghossian, Arshak and Sch{\"o}ning, Michael Josef and Katz, Evgeny and Halamek, Jan},
  title     = {Biocatalytic analysis of biomarkers for forensic identification of ethnicity between Caucasian and African American},
  series = {The analyst. August 2013},
  volume    = {Vol. 138},
  journal   = {The analyst. August 2013},
  publisher = {Royal Society of Chemistry},
  address   = {Cambridge},
  issn      = {1364-5528 (E-Journal); 0003-2654 (Print)},
  pages     = {6251 -- 6257},
  year      = {2013},
  language  = {en}
}
@article{SchusserMenzelBaeckeretal.2013,
  author    = {Schusser, Sebastian and Menzel, S. and B{\"a}cker, Matthias and Leinhos, Marcel and Poghossian, Arshak and Wagner, P. and Sch{\"o}ning, Michael Josef},
  title     = {Degradation of thin poly(lactic acid) films: characterization by capacitance-voltage, atomic force microscopy, scanning electron microscopy and contact-angle measurements},
  series = {Electrochimica Acta},
  volume    = {Vol. 113},
  journal   = {Electrochimica Acta},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {1873-3859 (E-Journal); 0013-4686 (Print)},
  pages     = {779 -- 784},
  year      = {2013},
  language  = {en}
}
@article{BaeckerSchusserPoghossianetal.2013,
  author    = {B{\"a}cker, Matthias and Schusser, Sebastian and Poghossian, Arshak and Sch{\"o}ning, Michael Josef},
  title     = {Degradationsverhalten bioabbaubarer Polymere : siliziumbasierte Sensorik zur {\"U}berwachung},
  series = {GIT Labor-Fachzeitschrift},
  journal   = {GIT Labor-Fachzeitschrift},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  issn      = {0016-3538},
  pages     = {32 -- 33},
  year      = {2013},
  language  = {de}
}
@article{BuniatyanHuckPoghossianetal.2013,
  author    = {Buniatyan, V. and Huck, Christina and Poghossian, Arshak and Aroutiounian, V. M. and Sch{\"o}ning, Michael Josef},
  title     = {BaxSr1-x TiO3/pc-Si heterojunction capacitance},
  series = {Armenian journal of physics},
  volume    = {6},
  journal   = {Armenian journal of physics},
  number    = {4},
  publisher = {National Academy of Sciences of Armenia},
  address   = {Yerevan},
  issn      = {1829-1171},
  pages     = {188 -- 197},
  year      = {2013},
  language  = {en}
}
@article{BuniatyanHuckPoghossianetal.2013,
  author    = {Buniatyan, V. and Huck, Christina and Poghossian, Arshak and Aroutiounian, V. M. and Sch{\"o}ning, Michael Josef},
  title     = {BaxSr1-x TiO3/pc-Si heterojunction},
  series = {Armenian journal of physics},
  volume    = {6},
  journal   = {Armenian journal of physics},
  number    = {4},
  publisher = {National Academy of Sciences of Armenia},
  address   = {Yerevan},
  issn      = {1829-1171},
  pages     = {177 -- 187},
  year      = {2013},
  language  = {en}
}
@article{PoghossianWeilCherstvyetal.2013,
  author    = {Poghossian, Arshak and Weil, M. and Cherstvy, A. G. and Sch{\"o}ning, Michael Josef},
  title     = {Electrical monitoring of polyelectrolyte multilayer formation by means of capacitive field-effect devices},
  series = {Analytical and bioanalytical chemistry},
  volume    = {405},
  journal   = {Analytical and bioanalytical chemistry},
  number    = {20},
  publisher = {Springer},
  address   = {Berlin},
  issn      = {1432-1130 ; 1618-2642},
  doi       = {10.1007/s00216-013-6951-9},
  pages     = {6425 -- 6436},
  year      = {2013},
  abstract  = {The semiconductor field-effect platform represents a powerful tool for detecting the adsorption and binding of charged macromolecules with direct electrical readout. In this work, a capacitive electrolyte-insulator-semiconductor (EIS) field-effect sensor consisting of an Al-p-Si-SiO2 structure has been applied for real-time in situ electrical monitoring of the layer-by-layer formation of polyelectrolyte (PE) multilayers (PEM). The PEMs were deposited directly onto the SiO2 surface without any precursor layer or drying procedures. Anionic poly(sodium 4-styrene sulfonate) and cationic weak polyelectrolyte poly(allylamine hydrochloride) have been chosen as a model system. The effect of the ionic strength of the solution, polyelectrolyte concentration, number and polarity of the PE layers on the characteristics of the PEM-modified EIS sensors have been studied by means of capacitance-voltage and constant-capacitance methods. In addition, the thickness, surface morphology, roughness and wettabilityof the PE mono- and multilayers have been characterised by ellipsometry, atomic force microscopy and water contact-angle methods, respectively. To explain potential oscillations on the gate surface and signal behaviour of the capacitive field-effect EIS sensor modified with a PEM, a simplified electrostatic model that takes into account the reduced electrostatic screening of PE charges by mobile ions within the PEM has been proposed and discussed.},
  language  = {en}
}
@article{HuckSchiffelsHerreraetal.2013,
  author    = {Huck, Christina and Schiffels, Johannes and Herrera, Cony N. and Schelden, Maximilian and Selmer, Thorsten and Poghossian, Arshak and Baumann, Marcus and Wagner, Patrick and Sch{\"o}ning, Michael Josef},
  title     = {Metabolic responses of Escherichia coli upon glucose pulses captured by a capacitive field-effect sensor},
  series = {Physica Status Solidi (A)},
  volume    = {210},
  journal   = {Physica Status Solidi (A)},
  number    = {5},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  issn      = {0031-8965},
  doi       = {10.1002/pssa.201200900},
  pages     = {926 -- 931},
  year      = {2013},
  abstract  = {Living cells are complex biological systems transforming metabolites taken up from the surrounding medium. Monitoring the responses of such cells to certain substrate concentrations is a challenging task and offers possibilities to gain insight into the vitality of a community influenced by the growth environment. Cell-based sensors represent a promising platform for monitoring the metabolic activity and thus, the "welfare" of relevant organisms. In the present study, metabolic responses of the model bacterium Escherichia coli in suspension, layered onto a capacitive field-effect structure, were examined to pulses of glucose in the concentration range between 0.05 and 2 mM. It was found that acidification of the surrounding medium takes place immediately after glucose addition and follows Michaelis-Menten kinetic behavior as a function of the glucose concentration. In future, the presented setup can, therefore, be used to study substrate specificities on the enzymatic level and may as well be used to perform investigations of more complex metabolic responses. Conclusions and perspectives highlighting this system are discussed.},
  language  = {en}
}
@article{BaeckerRakowskiPoghossianetal.2013,
  author    = {B{\"a}cker, Matthias and Rakowski, D. and Poghossian, Arshak and Biselli, Manfred and Wagner, Patrick and Sch{\"o}ning, Michael Josef},
  title     = {Chip-based amperometric enzyme sensor system for monitoring of bioprocesses by flow-injection analysis},
  series = {Journal of Biotechnology},
  volume    = {163},
  journal   = {Journal of Biotechnology},
  number    = {4},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0168-1656},
  doi       = {10.1016/j.jbiotec.2012.03.014},
  pages     = {371 -- 376},
  year      = {2013},
  abstract  = {A microfluidic chip integrating amperometric enzyme sensors for the detection of glucose, glutamate and glutamine in cell-culture fermentation processes has been developed. The enzymes glucose oxidase, glutamate oxidase and glutaminase were immobilized by means of cross-linking with glutaraldehyde on platinum thin-film electrodes integrated within a microfluidic channel. The biosensor chip was coupled to a flow-injection analysis system for electrochemical characterization of the sensors. The sensors have been characterized in terms of sensitivity, linear working range and detection limit. The sensitivity evaluated from the respective peak areas was 1.47, 3.68 and 0.28 μAs/mM for the glucose, glutamate and glutamine sensor, respectively. The calibration curves were linear up to a concentration of 20 mM glucose and glutamine and up to 10 mM for glutamate. The lower detection limit amounted to be 0.05 mM for the glucose and glutamate sensor, respectively, and 0.1 mM for the glutamine sensor. Experiments in cell-culture medium have demonstrated a good correlation between the glutamate, glutamine and glucose concentrations measured with the chip-based biosensors in a differential-mode and the commercially available instrumentation. The obtained results demonstrate the feasibility of the realized microfluidic biosensor chip for monitoring of bioprocesses.},
  language  = {en}
}
@article{SchusserLeinhosBaeckeretal.2013,
  author    = {Schusser, Sebastian and Leinhos, Marcel and B{\"a}cker, Matthias and Poghossian, Arshak and Wagner, Patrick and Sch{\"o}ning, Michael Josef},
  title     = {Impedance spectroscopy: A tool for real-time in situ monitoring of the degradation of biopolymers},
  series = {Physica Status Solidi (A)},
  volume    = {210},
  journal   = {Physica Status Solidi (A)},
  number    = {5},
  publisher = {Wiley},
  address   = {Weinheim},
  issn      = {1521-396X ; 0031-8965},
  doi       = {10.1002/pssa.201200941},
  pages     = {905 -- 910},
  year      = {2013},
  abstract  = {Investigation of the degradation kinetics of biodegradable polymers is essential for the development of implantable biomedical devices with predicted biodegradability. In this work, an impedimetric sensor has been applied for real-time and in situ monitoring of degradation processes of biopolymers. The sensor consists of two platinum thin-film electrodes covered by a polymer film to be studied. The benchmark biomedical polymer poly(D,L-lactic acid) (PDLLA) was used as a model system. PDLLA films were deposited on the sensor structure from a polymer solution by using the spin-coating method. The degradation kinetics of PDLLA films have been studied in alkaline solutions of pH 9 and 12 by means of an impedance spectroscopy (IS) method. Any changes in a polymer capacitance/resistance induced by water uptake and/or polymer degradation will modulate the global impedance of the polymer-covered sensor that can be used as an indicator of the polymer degradation. The degradation rate can be evaluated from the time-dependent impedance spectra. As expected, a faster degradation has been observed for PDLLA films exposed to pH 12 solution.},
  language  = {en}
}
@article{MoseleyHalamekKrameretal.2014,
  author    = {Moseley, Fiona and Halamek, Jan and Kramer, Friederike and Poghossian, Arshak and Sch{\"o}ning, Michael Josef and Katz, Evgeny},
  title     = {An enzyme-based reversible CNOT logic gate realized in a flow system},
  series = {Analyst},
  volume    = {139},
  journal   = {Analyst},
  number    = {8},
  publisher = {Royal Society of Chemistry},
  address   = {Cambridge},
  issn      = {1364-5528 (E-Journal) ; 0003-2654 (Print)},
  doi       = {10.1039/C4AN00133H},
  pages     = {1839 -- 1842},
  year      = {2014},
  abstract  = {An enzyme system organized in a flow device was used to mimic a reversible Controlled NOT (CNOT) gate with two input and two output signals. Reversible conversion of NAD⁺ and NADH cofactors was used to perform a XOR logic operation, while biocatalytic hydrolysis of p-nitrophenyl phosphate resulted in an Identity operation working in parallel. The first biomolecular realization of a CNOT gate is promising for integration into complex biomolecular networks and future biosensor/biomedical applications.},
  language  = {en}
}
@article{LeinhosSchusserBaeckeretal.2014,
  author    = {Leinhos, Marcel and Schusser, Sebastian and B{\"a}cker, Matthias and Poghossian, Arshak and Sch{\"o}ning, Michael Josef},
  title     = {Micromachined multi-parameter sensor chip for the control of polymer-degradation medium},
  series = {Physica Status Solidi (A) : special issue on engineering and functional interfaces},
  volume    = {211},
  journal   = {Physica Status Solidi (A) : special issue on engineering and functional interfaces},
  number    = {6},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  issn      = {1521-396X (E-Journal); 1862-6319 (E-Journal); 0031-8965 (Print); 1862-6300 (Print)},
  doi       = {10.1002/pssa.201330364},
  pages     = {1346 -- 1351},
  year      = {2014},
  abstract  = {It is well known that the degradation environment can strongly influence the biodegradability and kinetics of biodegradation processes of polymers. Therefore, besides the monitoring of the degradation process, it is also necessary to control the medium in which the degradation takes place. In this work, a micromachined multi-parameter sensor chip for the control of the polymer-degradation medium has been developed. The chip combines a capacitive field-effect pH sensor, a four-electrode electrolyte-conductivity sensor and a thin-film Pt-temperature sensor. The results of characterization of individual sensors are presented. In addition, the multi-parameter sensor chip together with an impedimetric polymer-degradation sensor was simultaneously characterized in degradation solutions with different pH and electrolyte conductivity. The obtained results demonstrate the feasibility of the multi-parameter sensor chip for the control of the polymer-degradation medium.},
  language  = {en}
}
@article{HuckPoghossianKerroumietal.2014,
  author    = {Huck, Christina and Poghossian, Arshak and Kerroumi, Iman and Schusser, Sebastian and B{\"a}cker, Matthias and Zander, Willi and Schubert, J{\"u}rgen and Buniatyan, Vahe V. and Martirosyan, Norayr W. and Wagner, Patrick and Sch{\"o}ning, Michael Josef},
  title     = {Multiparameter sensor chip with Barium Strontium Titanate as multipurpose material},
  series = {Electroanalysis},
  volume    = {26},
  journal   = {Electroanalysis},
  number    = {5},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  issn      = {1521-4109 (E-Journal); 1040-0397 (Print)},
  doi       = {10.1002/elan.201400076},
  pages     = {980 -- 987},
  year      = {2014},
  abstract  = {It is well known that biochemical and biotechnological processes are strongly dependent and affected by a variety of physico-chemical parameters such as pH value, temperature, pressure and electrolyte conductivity. Therefore, these quantities have to be monitored or controlled in order to guarantee a stable process operation, optimization and high yield. In this work, a sensor chip for the multiparameter detection of three physico-chemical parameters such as electrolyte conductivity, pH and temperature is realized using barium strontium titanate (BST) as multipurpose material. The chip integrates a capacitively coupled four-electrode electrolyte-conductivity sensor, a capacitive field-effect pH sensor and a thin-film Pt-temperature sensor. Due to the multifunctional properties of BST, it is utilized as final outermost coating layer of the processed sensor chip and serves as passivation and protection layer as well as pH-sensitive transducer material at the same time. The results of testing of the individual sensors of the developed multiparameter sensor chip are presented. In addition, a quasi-simultaneous multiparameter characterization of the sensor chip in buffer solutions with different pH value and electrolyte conductivity is performed. To study the sensor behavior and the suitability of BST as multifunctional material under harsh environmental conditions, the sensor chip was exemplarily tested in a biogas digestate.},
  language  = {en}
}
@article{BaeckerKramerHucketal.2014,
  author    = {B{\"a}cker, Matthias and Kramer, F. and Huck, Christina and Poghossian, Arshak and Bratov, A. and Abramova, N. and Sch{\"o}ning, Michael Josef},
  title     = {Planar and 3D interdigitated electrodes for biosensing applications: The impact of a dielectric barrier on the sensor properties},
  series = {Physica Status Solidi (A) - Applications and Materials Science},
  volume    = {211},
  journal   = {Physica Status Solidi (A) - Applications and Materials Science},
  number    = {6},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  issn      = {1521-396X (E-Journal); 1862-6319 (E-Journal); 0031-8965 (Print); 1862-6300 (Print)},
  doi       = {10.1002/pssa.201330416},
  pages     = {1357 -- 1363},
  year      = {2014},
  abstract  = {Planar and three-dimensional (3D) interdigitated electrodes (IDE) with electrode digits separated by an insulating barrier of different heights were electrochemically characterized and compared in terms of their sensing properties. Due to the impact of the surface resistance, both types of IDE structures display a non-linear behavior in low-ionic strength solutions. The experimental data were fitted to an electrical equivalent circuit and interpreted taking into account the surface-charge-governed properties. The effect of a charged polyelectrolyte layer electrostatically assembled onto the sensor surface on the surface resistance in solutions with different KCl concentration is studied. In case of the same electrode footprint, 3D-IDEs show a larger cell constant and a higher sensitivity to molecular adsorption than that of planar IDEs. The obtained results demonstrate the potential of 3D-IDEs as a new transducer structure for a direct label-free sensing of charged molecules.},
  language  = {en}
}
@article{HuckPoghossianBaeckeretal.2014,
  author    = {Huck, Christina and Poghossian, Arshak and B{\"a}cker, Matthias and Chaudhuri, S. and Zander, W. and Schubert, J. and Begoyan, V. K. and Buniatyan, V. V. and Wagner, P. and Sch{\"o}ning, Michael Josef},
  title     = {Capacitively coupled electrolyte-conductivity sensor based on high-k material of barium strontium titanate},
  series = {Sensors and actuators. B: Chemical},
  journal   = {Sensors and actuators. B: Chemical},
  number    = {198},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {1873-3077 (E-Journal); 0925-4005 (Print)},
  doi       = {10.1016/j.snb.2014.02.103},
  pages     = {102 -- 109},
  year      = {2014},
  language  = {en}
}
@article{WuBronderPoghossianetal.2014,
  author    = {Wu, Chunsheng and Bronder, Thomas and Poghossian, Arshak and Werner, Frederik and B{\"a}cker, Matthias and Sch{\"o}ning, Michael Josef},
  title     = {Label-free electrical detection of DNA with a multi-spot LAPS: First step towards light-addressable DNA chips},
  series = {Physica status solidi A : Applications and materials science},
  volume    = {211},
  journal   = {Physica status solidi A : Applications and materials science},
  number    = {6},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  issn      = {1521-396X (E-Journal); 1862-6319 (E-Journal); 0031-8965 (Print); 1862-6300 (Print)},
  doi       = {10.1002/pssa.201330442},
  pages     = {1423 -- 1428},
  year      = {2014},
  abstract  = {A multi-spot (4 × 4 spots) light-addressable potentiometric sensor (MLAPS) consisting of an Al-p-Si-SiO2 structure has been applied for the label-free electrical detection of DNA (deoxyribonucleic acid) immobilization and hybridization by the intrinsic molecular charge for the first time. Single-stranded probe ssDNA molecules (20 bases) were covalently immobilized onto the silanized SiO2 gate surface. The unspecific adsorption of mismatch ssDNA on the MLAPS gate surface was blocked by bovine serum albumin molecules. To reduce the screening effect and to achieve a high sensor signal, the measurements were performed in a low ionic-strength solution. The photocurrent-voltage (I-V) curves were simultaneously recorded on all 16 spots after each surface functionalization step. Large shifts of I-V curves of 25 mV were registered after the DNA immobilization and hybridization event. In contrast, a small potential shift (∼5 mV) was observed in case of mismatch ssDNA, revealing good specificity of the sensor. The obtained results demonstrate the potential of the MLAPS as promising transducer platform for the multi-spot label-free electrical detection of DNA molecules by their intrinsic molecular charge.},
  language  = {en}
}
@article{BaeckerSchusserPoghossianetal.2014,
  author    = {B{\"a}cker, Matthias and Schusser, Sebastian and Poghossian, Arshak and Sch{\"o}ning, Michael Josef},
  title     = {Multi-Parametererfassung mit siliziumbasiertem Sensorchip: Aus Drei mach Eins},
  series = {GIT Labor-Fachzeitschrift},
  journal   = {GIT Labor-Fachzeitschrift},
  number    = {2},
  publisher = {Wiley},
  issn      = {0016-3538},
  pages     = {28 -- 30},
  year      = {2014},
  language  = {de}
}
@article{PoghossianSchoening2014,
  author    = {Poghossian, Arshak and Sch{\"o}ning, Michael Josef},
  title     = {Label-free sensing of biomolecules with field-effect devices for clinical applications},
  series = {Electroanalysis},
  volume    = {26},
  journal   = {Electroanalysis},
  number    = {6},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  issn      = {1521-4109 (E-Journal); 1040-0397 (Print)},
  doi       = {10.1002/elan.201400073},
  pages     = {1197 -- 1213},
  year      = {2014},
  abstract  = {Among the variety of transducer concepts proposed for label-free detection of biomolecules, the semiconductor field-effect device (FED) is one of the most attractive platforms. As medical techniques continue to progress towards diagnostic and therapies based on biomarkers, the ability of FEDs for a label-free, fast and real-time detection of multiple pathogenic and physiologically relevant molecules with high specificity and sensitivity offers very promising prospects for their application in point-of-care and personalized medicine for an early diagnosis and treatment of diseases. The presented paper reviews recent advances and current trends in research and development of different FEDs for label-free, direct electrical detection of charged biomolecules by their intrinsic molecular charge. The authors are mainly focusing on the detection of the DNA hybridization event, antibody-antigen affinity reaction as well as clinically relevant biomolecules such as cardiac and cancer biomarkers.},
  language  = {en}
}
@article{PoghossianBaeckerMayeretal.2015,
  author    = {Poghossian, Arshak and B{\"a}cker, Matthias and Mayer, Dirk and Sch{\"o}ning, Michael Josef},
  title     = {Gating capacitive field-effect sensors by the charge of nanoparticle/molecule hybrids},
  series = {Nanoscale},
  journal   = {Nanoscale},
  publisher = {Royal Society of Chemistry (RSC)},
  address   = {Cambridge},
  issn      = {2040-3372 (E-Journal); 2040-3364 (Print)},
  doi       = {10.1039/C4NR05987E},
  pages     = {1023 -- 1031},
  year      = {2015},
  language  = {en}
}
@article{SchusserPoghossianBaeckeretal.2015,
  author    = {Schusser, Sebastian and Poghossian, Arshak and B{\"a}cker, Matthias and Krischer, M. and Leinhos, Marcel and Wagner, P. and Sch{\"o}ning, Michael Josef},
  title     = {An application of field-effect sensors for in-situ monitoring of degradation of biopolymers},
  series = {Sensors and actuators B: Chemical},
  volume    = {207, Part B},
  journal   = {Sensors and actuators B: Chemical},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {1873-3077 (E-Journal); 0925-4005 (Print)},
  doi       = {10.1016/j.snb.2014.10.058},
  pages     = {954 -- 959},
  year      = {2015},
  abstract  = {The characterization of the degradation kinetics of biodegradable polymers is mandatory with regard to their proper application. In the present work, polymer-modified electrolyte-insulator-semiconductor (PMEIS) field-effect sensors have been applied for in-situ monitoring of the pH-dependent degradation kinetics of the commercially available biopolymer poly(d,l-lactic acid) (PDLLA) in buffer solutions from pH 3 to pH 13. PDLLA films of 500 nm thickness were deposited on the surface of an Al-p-Si-SiO2-Ta2O5 structure from a polymer solution by means of spin-coating method. The PMEIS sensor is, in principle, capable to detect any changes in bulk, surface and interface properties of the polymer induced by degradation processes. A faster degradation has been observed for PDLLA films exposed to alkaline solutions (pH 9, pH 11 and pH 13).},
  language  = {en}
}
@article{WuBronderPoghossianetal.2015,
  author    = {Wu, Chunsheng and Bronder, Thomas and Poghossian, Arshak and Werner, Frederik and Sch{\"o}ning, Michael Josef},
  title     = {Label-free detection of DNA using light-addressable potentiometric sensor modified with a positively charged polyelectrolyte layer},
  series = {Nanoscale},
  volume    = {14},
  journal   = {Nanoscale},
  number    = {7},
  publisher = {Royal Society of Chemistry (RSC)},
  address   = {Cambridge},
  doi       = {10.1039/C4NR07225A},
  pages     = {6143 -- 6150},
  year      = {2015},
  abstract  = {A multi-spot (16 spots) light-addressable potentiometric sensor (MLAPS) consisting of an Al-p-Si-SiO2 structure modified with a weak polyelectrolyte layer of PAH (poly(allylamine hydrochloride)) was applied for the label-free electrical detection of DNA (deoxyribonucleic acid) immobilization and hybridization by the intrinsic molecular charge for the first time. To achieve a preferentially flat orientation of DNA strands and thus, to reduce the distance between the DNA charge and MLAPS surface, the negatively charged probe single-stranded DNAs (ssDNA) were electrostatically adsorbed onto the positively charged PAH layer using a simple layer-by-layer (LbL) technique. In this way, more DNA charge can be positioned within the Debye length, yielding a higher sensor signal. The surface potential changes in each spot induced due to the surface modification steps (PAH adsorption, probe ssDNA immobilization, hybridization with complementary target DNA (cDNA), non-specific adsorption of mismatched ssDNA) were determined from the shifts of photocurrent-voltage curves along the voltage axis. A high sensor signal of 83 mV was registered after immobilization of probe ssDNA onto the PAH layer. The hybridization signal increases from 5 mV to 32 mV with increasing the concentration of cDNA from 0.1 nM to 5 μM. In contrast, a small signal of 5 mV was recorded in the case of non-specific adsorption of fully mismatched ssDNA (5 μM). The obtained results demonstrate the potential of the MLAPS in combination with the simple and rapid LbL immobilization technique as a promising platform for the future development of multi-spot light-addressable label-free DNA chips with direct electrical readout.},
  language  = {en}
}