@article{MTMT:3183293, title = {Formation of novel hydrogel bio-anode by immobilization of biocatalyst in alginate/polyaniline/titanium-dioxide/graphite composites and its electrical performance}, url = {https://m2.mtmt.hu/api/publication/3183293}, author = {Szöllősi, Attila and Hoschke, Ágoston and Rezessyné, Szabó Judit and Bujna, Erika and Kun, Szilárd and Nguyen, Duc Quang}, doi = {10.1016/j.chemosphere.2017.01.095}, journal-iso = {CHEMOSPHERE}, journal = {CHEMOSPHERE}, volume = {174}, unique-id = {3183293}, issn = {0045-6535}, abstract = {A new bio-anode containing gel-entrapped bacteria in alginate/polyaniline/TiO2/graphite composites was constructed and electrically investigated. Alginate as dopant and template as well as entrapped gel was used for immobilization of microorganism cells. Increase of polyaniline concentration resulted an increase in the conductivity in gels. Addition of 0.01 and 0.02 g/mL polyaniline caused 6- fold and 10-fold higher conductivity, respectively. Furthermore, addition of 0.05 g/mL graphite powder caused 10-fold higher conductivity and 4- fold higher power density, respectively. The combination of polyaniline and graphite resulted 105-fold higher conductivity and 7-fold higher power-density output. Optimized concentrations of polyaniline and graphite powder were determined to be 0.02 g/mL and 0.05 g/mL, respectively. Modified hydrogel anode was successfully used in microbial fuel cell systems both in semi- and continuous operations modes. In semi-continuous mode, about 7.88 W/m3 power density was obtained after 13 h of fermentation. The glucose consumption rate was calculated to be about 7 mg glucose/h/1.2·107 CFU immobilized cells. Similar power density was observed in the continuous operation mode of the microbial fuel cell, and it was operated stably for more than 7 days. Our results are very promising for development of an improved microbial fuel cell with new type of bio-anode that have higher power density and can operate for long term.}, year = {2017}, eissn = {1879-1298}, pages = {58-65}, orcid-numbers = {Nguyen, Duc Quang/0000-0002-8548-4854} } @article{MTMT:2444026, title = {In vivo validation of the electronic depth control probes}, url = {https://m2.mtmt.hu/api/publication/2444026}, author = {Dombovári, Balázs Gábor and Fiáth, Richárd and Kerekes, Bálint Péter and Tóth, Emília and Wittner, Lucia and Horváth, Domonkos and Seidl, K and Herwik, S and Torfs, T and Paul, O and Ruther, P and Neves, H and Ulbert, István}, doi = {10.1515/bmt-2012-0102}, journal-iso = {BIOMED TECH}, journal = {BIOMEDIZINISCHE TECHNIK}, volume = {59}, unique-id = {2444026}, issn = {0013-5585}, abstract = {Abstract In this article, we evaluated the electrophysiological performance of a novel, high-complexity silicon probe array. This brain-implantable probe implements a dynamically reconfigurable voltage-recording device, coordinating large numbers of electronically switchable recording sites, referred to as electronic depth control (EDC). Our results show the potential of the EDC devices to record good-quality local field potentials, and single- and multiple-unit activities in cortical regions during pharmacologically induced cortical slow wave activity in an animal model.}, year = {2014}, eissn = {1862-278X}, pages = {283-289}, orcid-numbers = {Fiáth, Richárd/0000-0001-8732-2691; Kerekes, Bálint Péter/0000-0001-9542-8082; Wittner, Lucia/0000-0001-6800-0953; Horváth, Domonkos/0000-0001-7310-2890; Ulbert, István/0000-0001-9941-9159} } @article{MTMT:1815161, title = {Two-dimensional multi-channel neural probes with electronic depth control}, url = {https://m2.mtmt.hu/api/publication/1815161}, author = {Torfs, T and Aarts, A A A and Erismis, M A and Aslam, J and Yazicioglu, R F and Seidl, K and Herwik, S and Ulbert, István and Dombovári, Balázs Gábor and Fiáth, Richárd and Kerekes, Bálint Péter and Puers, R and Paul, O and Ruther, P and Van, Hoof C and Neves, H P}, doi = {10.1109/TBCAS.2011.2162840}, journal-iso = {IEEE T BIOMED CIRC S}, journal = {IEEE TRANSACTIONS ON BIOMEDICAL CIRCUITS AND SYSTEMS}, volume = {5}, unique-id = {1815161}, issn = {1932-4545}, abstract = {This paper presents multi-electrode arrays for in vivo neural recording applications incorporating the principle of electronic depth control (EDC), i.e., the electronic selection of recording sites along slender probe shafts independently for multiple channels. Two-dimensional (2D) arrays were realized using a commercial 0.5-μm complementary-metal-oxide-semiconductor (CMOS) process for the EDC circuits combined with post-CMOS micromachining to pattern the comb-like probes and the corresponding electrode metallization. A dedicated CMOS integrated front-end circuit was developed for pre-amplification and multiplexing of the neural signals recorded using these probes. 2D arrays with IrOx metal finish showed electrode impedances of 300 kΩ on average with a standard deviation of 175 kΩ. In vivo tests demonstrated the capability to simultaneously record multi-unit activity in addition to local field potentials on each of the available output channels using the electronic depth control circuitry, and to finely adjust the position of the recording sites along the probe shaft for an optimal signal-to-noise ratio. In addition, this depth control concept has been demonstrated in the electronic steering of electrodes selected simultaneously within thalamic sites in the rat. By enabling the selection and thus position fine-tuning of the individual recording sites after implantation, this new device significantly increases the amount of useful information that can be obtained from a single recording experiment. © 2011 IEEE.}, keywords = {IN-VIVO; PROBES; Signal to noise ratio; In-vivo tests; Multi-channel; Local field potentials; Standard deviation; Two dimensional; Dielectric devices; MULTIELECTRODE ARRAYS; Rat control; Two dimensional (2D) arrays; Signal to noise; Post-CMOS; Output channels; New devices; Neural signals; Multiple channels; Multi-unit activity; Front-end circuits; Electronic steering; Electrode impedance; Depth control; Comb-like; 2D arrays; neural probes; multi-electrode arrays; implantable biomedical devices; Complementary-metal-oxide-semiconductor (CMOS) integrated circuits}, year = {2011}, eissn = {1940-9990}, pages = {403-412}, orcid-numbers = {Ulbert, István/0000-0001-9941-9159; Fiáth, Richárd/0000-0001-8732-2691; Kerekes, Bálint Péter/0000-0001-9542-8082} } @article{MTMT:1341714, title = {Short and long term biocompatibility of NeuroProbes silicon probes.}, url = {https://m2.mtmt.hu/api/publication/1341714}, author = {Grand, László and Wittner, Lucia and Herwik, S and Gothelid, E and Ruther, P and Oscarsson, S and Neves, H and Dombovári, Balázs Gábor and Csercsa, Richárd and Karmos, György and Ulbert, István}, doi = {10.1016/j.jneumeth.2010.04.009}, journal-iso = {J NEUROSCI METH}, journal = {JOURNAL OF NEUROSCIENCE METHODS}, volume = {189}, unique-id = {1341714}, issn = {0165-0270}, abstract = {Brain implants provide exceptional tools to understand and restore cerebral functions. The utility of these devices depends crucially on their biocompatibility and long term viability. We addressed these points by implanting non-functional, NeuroProbes silicon probes, without or with hyaluronic acid (Hya), dextran (Dex), dexamethasone (DexM), Hya+DexM coating, into rat neocortex. Light and transmission electron microscopy were used to investigate neuronal survival and glial response. The surface of explanted probes was examined in the scanning electron microscope. We show that blood vessel disruption during implantation could induce considerable tissue damage. If, however, probes could be inserted without major bleeding, light microscopical evidence of damage to surrounding neocortical tissue was much reduced. At distances less than 100mum from the probe track a considerable neuron loss ( approximately 40%) occurred at short survival times, while the neuronal numbers recovered close to control levels at longer survival. Slight gliosis was observed at both short and long term survivals. Electron microscopy showed neuronal cell bodies and synapses close (<10mum) to the probe track when bleeding could be avoided. The explanted probes were usually partly covered by tissue residue containing cells with different morphology. Our data suggest that NeuroProbes silicon probes are highly biocompatible. If major blood vessel disruption can be avoided, the low neuronal cell loss and gliosis should provide good recording and stimulating results with future functional probes. We found that different bioactive molecule coatings had small differential effects on neural cell numbers and gliosis, with optimal results achieved using the DexM coated probes.}, year = {2010}, eissn = {1872-678X}, pages = {216-229}, orcid-numbers = {Wittner, Lucia/0000-0001-6800-0953; Ulbert, István/0000-0001-9941-9159} } @article{MTMT:109455, title = {Massively parallel recording of unit and local field potentials with silicon-based electrodes}, url = {https://m2.mtmt.hu/api/publication/109455}, author = {Csicsvari, J and Henze, DA and Jamieson, B and Harris, KD and Sirota, A and Barthó, Péter and Wise, KD and Buzsáki, György}, doi = {10.1152/jn.00116.2003}, journal-iso = {J NEUROPHYSIOL}, journal = {JOURNAL OF NEUROPHYSIOLOGY}, volume = {90}, unique-id = {109455}, issn = {0022-3077}, year = {2003}, eissn = {1522-1598}, pages = {1314-1323} }