@article{SchoeningAbouzarIngebrandtetal.2006, author = {Sch{\"o}ning, Michael Josef and Abouzar, Maryam H. and Ingebrandt, Sven and Platen, Johannes and Offenh{\"a}usser, Andreas and Poghossian, Arshak}, title = {Towards label-free detection of charged macromolecules using field-effect-based structures : Scaling down from capacitive EIS sensor over ISFET to nano-scale devices}, series = {Nanostructured materials and hybrid composites for gas sensors and biomedical applications : symposium held April 18-20, 2006, San Francisco , California, U.S.A.}, journal = {Nanostructured materials and hybrid composites for gas sensors and biomedical applications : symposium held April 18-20, 2006, San Francisco , California, U.S.A.}, number = {paper 0915-R05-04}, editor = {Comini, Elisabetta}, isbn = {9781558998711}, pages = {89 -- 94}, year = {2006}, language = {en} } @article{TakenagaSchneiderErbayetal.2015, author = {Takenaga, Shoko and Schneider, Benno and Erbay, E. and Biselli, Manfred and Schnitzler, Thomas and Sch{\"o}ning, Michael Josef and Wagner, Torsten}, title = {Fabrication of biocompatible lab-on-chip devices for biomedical applications by means of a 3D-printing process}, series = {Physica status solidi (a)}, volume = {212}, journal = {Physica status solidi (a)}, number = {6}, publisher = {Wiley}, address = {Weinheim}, issn = {1862-6319}, doi = {10.1002/pssa.201532053}, pages = {1347 -- 1352}, year = {2015}, abstract = {A new microfluidic assembly method for semiconductor-based biosensors using 3D-printing technologies was proposed for a rapid and cost-efficient design of new sensor systems. The microfluidic unit is designed and printed by a 3D-printer in just a few hours and assembled on a light-addressable potentiometric sensor (LAPS) chip using a photo resin. The cell growth curves obtained from culturing cells within microfluidics-based LAPS systems were compared with cell growth curves in cell culture flasks to examine biocompatibility of the 3D-printed chips. Furthermore, an optimal cell culturing within microfluidics-based LAPS chips was achieved by adjusting the fetal calf serum concentrations of the cell culture medium, an important factor for the cell proliferation.}, language = {en} } @article{MolinnusBaeckerIkenetal.2015, author = {Molinnus, Denise and B{\"a}cker, Matthias and Iken, Heiko and Poghossian, Arshak and Keusgen, Michael and Sch{\"o}ning, Michael Josef}, title = {Concept for a biomolecular logic chip with an integrated sensor and actuator function}, series = {Physica status solidi (a)}, volume = {212}, journal = {Physica status solidi (a)}, number = {6}, publisher = {Wiley}, address = {Weinheim}, issn = {1862-6319}, doi = {10.1002/pssa.201431913}, pages = {1382 -- 1388}, year = {2015}, abstract = {A concept for a new generation of an integrated multi-functional biosensor/actuator system is developed, which is based on biomolecular logic principles. Such a system is expected to be able to detect multiple biochemical input signals simultaneously and in real-time and convert them into electrical output signals with logical operations such as OR, AND, etc. The system can be designed as a closed-loop drug release device triggered by an enzyme logic gate, while the release of the drug induced by the actuator at the required dosage and timing will be controlled by an additional drug sensor. Thus, the system could help to make an accurate and specific diagnosis. The presented concept is exemplarily demonstrated by using an enzyme logic gate based on a glucose/glucose oxidase system, a temperature-responsive hydrogel mimicking the actuator function and an insulin (drug) sensor. In this work, the results of functional testing of individual amperometric glucose and insulin sensors as well as an impedimetric sensor for the detection of the hydrogel swelling/shrinking are presented.}, language = {en} } @article{WarmerWagnerSchoeningetal.2015, author = {Warmer, Johannes and Wagner, Patrick and Sch{\"o}ning, Michael Josef and Kaul, Peter}, title = {Detection of triacetone triperoxide using temperature cycled metal-oxide semiconductor gas sensors}, series = {Physica status solidi (a)}, volume = {212}, journal = {Physica status solidi (a)}, number = {6}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {1862-6319}, doi = {10.1002/pssa.201431882}, pages = {1289 -- 1298}, year = {2015}, language = {en} } @article{DelleHuckBaeckeretal.2015, author = {Delle, Lotta E. and Huck, Christina and B{\"a}cker, Matthias and M{\"u}ller, Frank and Grandthyll, Samuel and Jacobs, Karin and Lilischkis, Rainer and Vu, Xuan T. and Sch{\"o}ning, Michael Josef and Wagner, Patrick and Thoelen, Roland and Weil, Maryam and Ingebrandt, Sven}, title = {Impedimetric immunosensor for the detection of histamine based on reduced graphene oxide}, series = {Physica status solidi (a)}, volume = {212}, journal = {Physica status solidi (a)}, number = {6}, publisher = {Wiley}, address = {Weinheim}, issn = {1862-6319}, doi = {10.1002/pssa.201431863}, pages = {1327 -- 1334}, year = {2015}, language = {en} } @article{HenkenOosterhuisOehlschlaegeretal.2012, author = {Henken, F. E. and Oosterhuis, K. and {\"O}hlschl{\"a}ger, Peter and Bosch, L. and Hooijberg, E. and Haanen, J. B. A. G. and Steenbergen, R. D. M.}, title = {Preclinical safety evaluation of DNA vaccines encoding modified HPV16 E6 and E7}, series = {Vaccine}, volume = {30}, journal = {Vaccine}, number = {28}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0264-410X}, doi = {10.1016/j.vaccine.2012.04.013}, pages = {4259 -- 4266}, year = {2012}, abstract = {Persistent infection with high-risk human papillomaviruses (hrHPV) can result in the formation of anogenital cancers. As hrHPV proteins E6 and E7 are required for cancer initiation and maintenance, they are ideal targets for immunotherapeutic interventions. Previously, we have described the development of DNA vaccines for the induction of HPV16 E6 and E7 specific T cell immunity. These vaccines consist of 'gene-shuffled' (SH) versions of HPV16 E6 and E7 that were fused to Tetanus Toxin Fragment C domain 1 (TTFC) and were named TTFC-E6SH and TTFC-E7SH. Gene-shuffling was performed to avoid the risk of inducing malignant transformation at the vaccination site. Here, we describe the preclinical safety evaluation of these candidate vaccines by analysis of their transforming capacity in vitro using established murine fibroblasts (NIH 3T3 cells) and primary human foreskin keratinocytes (HFKs). We demonstrate that neither ectopic expression of TTFC-E6SH and TTFC-E7SH alone or in combination enabled NIH 3T3 cells to form colonies in soft agar. In contrast, expression of HPV16 E6WT and E7WT alone or in combination resulted in effective transformation. Similarly, retroviral transduction of HFKs from three independent donors with both TTFC-E6SH and TTFC-E7SH alone or in combination did not show any signs of immortalization. In contrast, the combined expression of E6WT and E7WT induced immortalization in HFKs from all donors. Based on these results we consider it justified to proceed to clinical evaluation of DNA vaccines encoding TTFC-E6SH and TTFC-E7SH in patients with HPV16 associated (pre)malignancies.}, language = {en} } @article{ImmelGruetzkeSpaeteetal.2012, author = {Immel, Timo and Gr{\"u}tzke, Martin and Sp{\"a}te, Anne-Katrin and Groth, Ulrich and {\"O}hlschl{\"a}ger, Peter and Huhn, Thomas}, title = {Synthesis and X-ray structure analysis of a heptacoordinate titanium(IV)-bis-chelate with enhanced in vivo antitumor efficacy}, series = {Chemical Communications}, volume = {48}, journal = {Chemical Communications}, number = {46}, publisher = {Royal Society of Chemistry}, address = {Cambridge}, issn = {1364-548X}, doi = {10.1039/C2CC31624B}, pages = {5790 -- 5792}, year = {2012}, abstract = {Chelate stabilization of a titanium(IV)-salan alkoxide by ligand exchange with 2,6-pyridinedicarboxylic acid (dipic) resulted in heptacoordinate complex 3 which is not redox-active, stable on silica gel and has increased aqueous stability. 3 is highly toxic in HeLa S3 and Hep G2 and has enhanced antitumor efficacy in a mouse cervical-cancer model.}, language = {en} } @article{BronderPoghossianSchejaetal.2015, author = {Bronder, Thomas and Poghossian, Arshak and Scheja, Sabrina and Wu, Chunsheng and Keusgen, Michael and Mewes, Dieter and Sch{\"o}ning, Michael Josef}, title = {DNA Immobilization and Hybridization Detection by the Intrinsic Molecular Charge Using Capacitive Field-Effect Sensors Modified with a Charged Weak Polyelectrolyte Layer}, series = {Applied Materials \& Interfaces}, volume = {36}, journal = {Applied Materials \& Interfaces}, number = {7}, publisher = {American Chemical Society}, address = {Washington, DC}, doi = {10.1021/acsami.5b05146}, pages = {20068 -- 20075}, year = {2015}, abstract = {Miniaturized setup, compatibility with advanced micro- and nanotechnologies, and ability to detect biomolecules by their intrinsic molecular charge favor the semiconductor field-effect platform as one of the most attractive approaches for the development of label-free DNA chips. In this work, a capacitive field-effect EIS (electrolyte-insulator-semiconductor) sensor covered with a layer-by-layer prepared, positively charged weak polyelectrolyte layer of PAH (poly(allylamine hydrochloride)) was used for the label-free electrical detection of DNA (deoxyribonucleic acid) immobilization and hybridization. The negatively charged probe single-stranded DNA (ssDNA) molecules were electrostatically adsorbed onto the positively charged PAH layer, resulting in a preferentially flat orientation of the ssDNA molecules within the Debye length, thus yielding a reduced charge-screening effect and a higher sensor signal. Each sensor-surface modification step (PAH adsorption, probe ssDNA immobilization, hybridization with complementary target DNA (cDNA), reducing an unspecific adsorption by a blocking agent, incubation with noncomplementary DNA (ncDNA) solution) was monitored by means of capacitance-voltage and constant-capacitance measurements. In addition, the surface morphology of the PAH layer was studied by atomic force microscopy and contact-angle measurements. High hybridization signals of 34 and 43 mV were recorded in low-ionic strength solutions of 10 and 1 mM, respectively. In contrast, a small signal of 4 mV was recorded in the case of unspecific adsorption of fully mismatched ncDNA. The density of probe ssDNA and dsDNA molecules as well as the hybridization efficiency was estimated using the experimentally measured DNA immobilization and hybridization signals and a simplified double-layer capacitor model. The results of field-effect experiments were supported by fluorescence measurements, verifying the DNA-immobilization and hybridization event.}, language = {en} } @article{OberlaenderJildehKirchneretal.2015, author = {Oberl{\"a}nder, Jan and Jildeh, Zaid B. and Kirchner, Patrick and Wendeler, Luisa and Bromm, Alexander and Iken, Heiko and Wagner, Patrick and Keusgen, Michael and Sch{\"o}ning, Michael Josef}, title = {Study of Interdigitated Electrode Arrays Using Experiments and Finite Element Models for the Evaluation of Sterilization Processes}, series = {Sensors}, volume = {15}, journal = {Sensors}, number = {10}, publisher = {MDPI}, address = {Basel}, issn = {1424-8220}, doi = {10.3390/s151026115}, pages = {26115 -- 26127}, year = {2015}, abstract = {In this work, a sensor to evaluate sterilization processes with hydrogen peroxide vapor has been characterized. Experimental, analytical and numerical methods were applied to evaluate and study the sensor behavior. The sensor set-up is based on planar interdigitated electrodes. The interdigitated electrode structure consists of 614 electrode fingers spanning over a total sensing area of 20 mm2. Sensor measurements were conducted with and without microbiological spores as well as after an industrial sterilization protocol. The measurements were verified using an analytical expression based on a first-order elliptical integral. A model based on the finite element method with periodic boundary conditions in two dimensions was developed and utilized to validate the experimental findings.}, language = {en} } @article{BrahmaMusioIsmayilovaetal.2015, author = {Brahma, Aischarya and Musio, Biagia and Ismayilova, Uliviya and Nikbin, Nikzad and Kamptmann, Sonja B. and Siegert, Petra and Jeromin, G{\"u}nter Erich and Ley, Steven and Pohl, Martina}, title = {An orthogonal biocatalytic approach for the safe generation and use of HCN in a multi-step continuous preparation of chiral O-acetylcyanohydrins}, series = {Synlett}, journal = {Synlett}, number = {Publ. online 29.09.2015}, publisher = {Thieme}, address = {Stuttgart}, issn = {0936-5214 (Print) ; 1437-2096 (e-Journal)}, doi = {10.1055/s-0035-1560644}, year = {2015}, language = {de} }