@article{TippkoetterAlKaidyWollnyetal.2013,
  author    = {Tippk{\"o}tter, Nils and Al-Kaidy, Huschyar and Wollny, Steffen and Ulber, Roland},
  title     = {Functionalized magnetizable particles for downstream processing in single-use systems},
  series = {Chemie Ingenieur Technik},
  volume    = {85},
  journal   = {Chemie Ingenieur Technik},
  number    = {1-2: Special Issue: Single-Use Technology},
  publisher = {Wiley},
  address   = {Weinheim},
  doi       = {10.1002/cite.201200130},
  pages     = {76 -- 86},
  year      = {2013},
  abstract  = {Biotechnological downstream processing is usually an elaborate procedure, requiring a multitude of unit operations to isolate the target component. Besides the disadvantageous space-time yield, the risks of cross-contaminations and product loss grow fast with the complexity of the isolation procedure. A significant reduction of unit operations can be achieved by application of magnetic particles, especially if these are functionalized with affinity ligands. As magnetic susceptible materials are highly uncommon in biotechnological processes, target binding and selective separation of such particles from fermentation or reactions broths can be done in a single step. Since the magnetizable particles can be produced from iron salts and low priced polymers, a single-use implementation of these systems is highly conceivable. In this article, the principles of magnetizable particles, their synthesis and functionalization are explained. Furthermore, applications in the area of reaction engineering, microfluidics and downstream processing are discussed focusing on established single-use technologies and development potential.},
  language  = {en}
}
@article{ThielTippkoetterSucketal.2013,
  author    = {Thiel, Alexander and Tippk{\"o}tter, Nils and Suck, Kirstin and Sohling, Ulrich and Ruf, Friedrich and Ulber, Roland},
  title     = {New zeolite adsorbents for downstream processing of polyphenols from renewable resources},
  series = {Engineering in Life Sciences},
  volume    = {13},
  journal   = {Engineering in Life Sciences},
  number    = {3},
  publisher = {Wiley},
  address   = {Weinheim},
  doi       = {10.1002/elsc.201200188},
  pages     = {239 -- 246},
  year      = {2013},
  abstract  = {Commercial materials with polyvinylpolypyrrolidone and polymeric amberlites (XAD7HP, XAD16) are commonly used for the adsorptive downstream processing of polyphenols from renewable resources. In this study, beta-zeolite-based adsorbent systems were examined, and their properties were compared to organic resins. Batch adsorption experiments were conducted with synthetic solutions of major polyphenols. Adsorption isotherms and desorption characteristics of individual adsorbent were determined based on these results. Maximum adsorption capacities were calculated using the Langmuir model. For example, the zeolites had capacities up to 203.2 mg/g for ferulic acid. To extend these results to a complex system, additional experiments were performed on rapeseed meal and wheat seed extracts as representative renewable resources. HPLC analysis showed that with 7.5\% w/v, which is regarded as the optimum amount of zeolites, zeolites A and B could bind 100\% of the major polyphenols as well as release polyphenols at high yields. Additionally, regeneration experiments were performed with isopropyl alcohol at 99°C to evaluate how zeolites regenerate under mild conditions. The results showed only a negligible loss of adsorption capacity and no loss of desorption capacity. In summary, it was concluded that beta-zeolites were promising adsorbents for developing new processes to isolate polyphenols from renewable resources.},
  language  = {en}
}
@article{AlKaidyDuweHusteretal.2014,
  author    = {Al-Kaidy, Huschyar and Duwe, Anna and Huster, Manuel and Muffler, Kai and Schlegel, Christin and Sieker, Tim and Stadtm{\"u}ller, Ralf and Tippk{\"o}tter, Nils and Ulber, Roland},
  title     = {Biotechnologie und Bioverfahrenstechnik - Vom ersten Ullmanns Artikel bis hin zu aktuellen Forschungsthemen},
  series = {Chemie Ingenieur Technik},
  volume    = {86},
  journal   = {Chemie Ingenieur Technik},
  number    = {12},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  issn      = {0009-286X},
  doi       = {10.1002/cite.201400083},
  pages     = {2215 -- 2225},
  year      = {2014},
  abstract  = {Biotechnologie und die mit ihr verbundenen technischen Prozesse pr{\"a}gen seit Jahrtausenden die Entwicklung der Menschheit. Ausgehend von empirischen Verfahren, insbesondere zur Herstellung von Lebensmitteln und t{\"a}glichen Gebrauchsg{\"u}tern, haben sich diese Disziplinen zu einem der innovativsten Zukunftsfelder entwickelt. Durch das immer detailliertere Verst{\"a}ndnis zellul{\"a}rer Vorg{\"a}nge k{\"o}nnen mittlerweile Produktionsst{\"a}mme gezielt optimiert werden. Im Zusammenspiel mit moderner Prozesstechnik k{\"o}nnen so eine Vielzahl von Bulk- und Feinchemikalien sowie Pharmazeutika effizient hergestellt werden. In diesem Artikel werden exemplarisch einige der aktuellen Trends vorgestellt.},
  language  = {de}
}
@article{WiesenTippkoetterMuffleretal.2014,
  author    = {Wiesen, Sebastian and Tippk{\"o}tter, Nils and Muffler, Kai and Suck, Kirstin and Sohling, Ulrich and Ruf, Nils and Ulber, Roland},
  title     = {Adsorptive Vorbehandlung von Rohglycerin f{\"u}r die 1,3-Propandiol Fermentation mit Clostridium diolis},
  series = {Chemie Ingenieur Technik},
  volume    = {86},
  journal   = {Chemie Ingenieur Technik},
  number    = {1-2},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  doi       = {10.1002/cite.201300080},
  pages     = {129 -- 135},
  year      = {2014},
  abstract  = {Bei der Gewinnung von Fetts{\"a}uren aus Pflanzen{\"o}len, z. B. zur Herstellung von Biopolymeren, oder bei der Biodiesel- und Seifenproduktion, f{\"a}llt Glycerin als Nebenprodukt an. Bei der Biokonversion dieses Rohstoffes zu 1,3-Propandiol wird der Produktionsorganismus Clostridium diolis durch Verunreinigungen im Rohglycerin gehemmt. Als inhibierende Substanzen konnten freie Fetts{\"a}uren identifiziert werden. Mithilfe eines adsorptiven Aufarbeitungsverfahrens ist es gelungen, die Fetts{\"a}uren zu entfernen und die Konversionseffizienz zu 1,3-Propandiol zu erh{\"o}hen.},
  language  = {de}
}
@article{TippkoetterWollnySucketal.2014,
  author    = {Tippk{\"o}tter, Nils and Wollny, Steffen and Suck, Kirstin and Sohling, Ulrich and Ruf, Friedrich and Ulber, Roland},
  title     = {Recycling of spent oil bleaching earth as source of glycerol for the anaerobic production of acetone, butanol, and ethanol with Clostridium diolis and lipolytic Clostridium lundense},
  series = {Engineering in Life Sciences},
  volume    = {14},
  journal   = {Engineering in Life Sciences},
  number    = {4},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  issn      = {1618-2863},
  doi       = {10.1002/elsc.201300113},
  pages     = {425 -- 432},
  year      = {2014},
  abstract  = {A major part of edible oil is subjected to bleaching procedures, primarily with minerals applied as adsorbers. Their recycling is currently done either by regaining the oil via organic solvent extraction or by using the spent bleaching earth (SBE) as additive for animal feed, etc. As a new method, the reutilization of the by-product SBE for the microbiologic formation of acetone, butanol, and ethanol (ABE) is presented as proof-of-concept. The SBE was taken from a palm oil cleaning process. The recycling concept is based on the application of lipolytic clostridia strains. Due to considerably long fermentation times, co-fermentation with Candida rugosa and enzymatic hydrolyses of the bound oil with a subsequent clostridia fermentation are shown as alternative routes. Anaerobic fermentations under comparison of different clostridia strains were performed with glycerol media, enzymatically hydrolyzed palm oil and SBE. Solutes, side product compositions and productivities were quantified via HPLC. A successful production of ABE solutes from SBE has been done with a yield of 0.15 g butanol per gram of bound glycerol. Thus, the biotechnological recycling of the waste stream is possible in principle. Inhibition of the substrate suspension has been observed. A chromatographic ion-exchange of substrates increased the biomass concentration.},
  language  = {en}
}
@article{PasteurTippkoetterKampeisetal.2014,
  author    = {Pasteur, Aline and Tippk{\"o}tter, Nils and Kampeis, Percy and Ulber, Roland},
  title     = {Optimization of high gradient magnetic separation filter units for the purification of fermentation products},
  series = {IEEE TRANSACTIONS ON MAGNETICS},
  volume    = {50},
  journal   = {IEEE TRANSACTIONS ON MAGNETICS},
  number    = {10},
  publisher = {IEEE},
  address   = {New York, NY},
  issn      = {0018-9464},
  doi       = {10.1109/TMAG.2014.2325535},
  pages     = {Artikel 5000607},
  year      = {2014},
  abstract  = {High gradient magnetic separation (HGMS) has been established since the early 1970s. A more recent application of these systems is the use in bioprocesses. To integrate the HGMS in a fermentation process, it is necessary to optimize the separation matrix with regard to the magnetic separation characteristics and permeability of the non-magnetizable components of the fermentation broth. As part of the work presented here, a combined fluidic and magnetic force finite element model simulation was created using the software COMSOL Multiphysics and compared with separation experiments. Finally, as optimal lattice orientation of the separation matrix, a transversal rhombohedral arrangement was defined. The high suitability of the new filter matrix has been verified by separation experiments.},
  language  = {en}
}
@article{ThielMufflerTippkoetteretal.2015,
  author    = {Thiel, Alexander and Muffler, Kai and Tippk{\"o}tter, Nils and Suck, Kirstin and Sohling, Ulrich and Ruf, Friedrich and Ulber, Roland},
  title     = {Aufarbeitung von Polyphenolen aus Weizen mittels Zeolithen am Beispiel der Ferulas{\"a}ure},
  series = {Chemie IngenieurTechnik},
  volume    = {87},
  journal   = {Chemie IngenieurTechnik},
  number    = {1-2},
  publisher = {Wiley},
  address   = {Weinheim},
  doi       = {10.1002/cite.201400031},
  pages     = {128 -- 136},
  year      = {2015},
  abstract  = {Aufarbeitung von Polyphenolen aus Weizenmittels Zeolithen am Beispiel der Ferulasa¨ ureAlexander Thiel1, Kai Muffler1, Nils Tippko¨ tter1, Kirstin Suck2, Ulrich Sohling2, Friedrich Ruf3und Roland Ulber1,*DOI: 10.1002/cite.201400031Bei der Ferulasa¨ure handelt es sich um einen Wertstoff, der aus Weizen gewonnen und in der Lebensmittel- und Pharma-industrie eingesetzt werden kann. Der Einsatz von Weizen als nachwachsende Rohstoffquelle ist allerdings nur dann wirt-schaftlich durchfu¨hrbar, wenn eine Prozessintegration in die bestehenden industriellen Verfahren gewa¨hrleistet oder einedirekte Konkurrenz zur Mehl- und Sta¨rkeindustrie vermieden werden kann. In diesem Artikel wird ein Verfahren aufge-zeigt, welches hohe Ausbeuten ermo¨glicht und eine Konkurrenz zu bestehenden Verwertungspfaden vermeidet.},
  language  = {de}
}
@article{SchumannRoginSchneideretal.2015,
  author    = {Schumann, Christiane and Rogin, Sabine and Schneider, Horst and Tippk{\"o}tter, Nils and Oster, J{\"u}rgen and Kampeis, Percy},
  title     = {Simultane Atline-Quantifizierung von Magnetpartikeln und Mikroorganismen bei einer HGMS-Filtration},
  series = {Chemie Ingenieur Technik},
  volume    = {87},
  journal   = {Chemie Ingenieur Technik},
  number    = {1-2},
  doi       = {10.1002/cite.201300158},
  pages     = {137 -- 149},
  year      = {2015},
  abstract  = {Es wird eine neue Atline-Messmethode vorgestellt, mit der w{\"a}hrend einer Hochgradienten-Magnetseparation (HGMS)-Filtration eine simultane Quantifizierung von Magnetpartikeln und Mikroorganismen im Filtrat vorgenommen werden kann. Dabei gelingt die Quantifizierung signifikant besser als mit bisher verwendeten Messmethoden. Mit dieser Methode ist es m{\"o}glich, die Trennleistung einer HGMS-Filtration zu bestimmen und einen Filterdurchbruch durch Konzentrationsanstiege im Bereich einiger µg L-1 von Magnetpartikeln im Filtrat fr{\"u}hzeitig zu detektieren, ohne dass nennenswerte Partikelmengen verloren gehen.},
  language  = {de}
}
@article{ThielMufflerTippkoetteretal.2015,
  author    = {Thiel, Alexander and Muffler, Kai and Tippk{\"o}tter, Nils and Suck, Kirstin and Sohling, Ulrich and Hruschka, Steffen M. and Ulber, Roland},
  title     = {A novel integrated downstream processing approach to recover sinapic acid, phytic acid and proteins from rapeseed meal},
  series = {Journal of Chemical Technology and Biotechnology},
  volume    = {90},
  journal   = {Journal of Chemical Technology and Biotechnology},
  number    = {11},
  publisher = {Wiley},
  address   = {Weinheim},
  doi       = {10.1002/jctb.4664},
  pages     = {1999 -- 2006},
  year      = {2015},
  abstract  = {BACKGROUND Currently, several techniques exist for the downstream processing of protein, phytic acid and sinapic acid from rapeseed and rapeseed meal, but no technique has been developed to separate all of the components in one process. In this work, two new downstream processing strategies focusing on recovering sinapic acid, phytic acid and protein from rapeseed meal were established. RESULTS The sinapic acid content was enhanced by a factor of 4.5 with one method and 5.1 with the other. The isolation of sinapic acid was accomplished using a zeolite-based adsorbent with high adsorptive and optimal desorption characteristics. Phytic acid was isolated using the anion-exchange resin Purolite A200®. In addition, the processes resulted in two separated protein fractions. The ratios of globulin and albumin ratio to the total protein were 59.2\% and 40.1\%, respectively. The steps were then combined in two different ways: (a) a 'sequential process' using the zeolite and A200 in batch processes; and (b) a 'parallel process' using only A200 in a chromatographic system to separate all of the compounds. CONCLUSIONS It can be concluded that isolation of all three components was possible in both processes. These could enhance the added value of current processes using rapeseed meal as a protein source. © 2015 Society of Chemical Industry},
  language  = {en}
}
@article{AlKaidyDuweHusteretal.2015,
  author    = {Al-Kaidy, Huschyar and Duwe, Anna and Huster, Manuel and Muffler, Kai and Schlegel, Christin and Tim, Sieker and Stadtm{\"u}ller, Ralf and Tippk{\"o}tter, Nils and Ulber, Roland},
  title     = {Biotechnology and bioprocess engineering - from the first ullmann's article to recent trends},
  series = {ChemBioEng Reviews},
  volume    = {2},
  journal   = {ChemBioEng Reviews},
  number    = {3},
  publisher = {Wiley},
  address   = {Weinheim},
  doi       = {10.1002/cben.201500008},
  pages     = {175 -- 184},
  year      = {2015},
  abstract  = {For several thousand years, biotechnology and its associated technical processes have had a great impact on the development of mankind. Based on empirical methods, in particular for the production of foodstuffs and daily commodities, these disciplines have become one of the most innovative future issues. Due to the increasing detailed understanding of cellular processes, production strains can now be optimized. In combination with modern bioprocesses, a variety of bulk and fine chemicals as well as pharmaceuticals can be produced efficiently. In this article, some of the current trends in biotechnology are discussed.},
  language  = {en}
}
@article{AlKaidyTippkoetter2016,
  author    = {Al-Kaidy, Huschyar and Tippk{\"o}tter, Nils},
  title     = {Superparamagnetic hydrophobic particles as shell material for digital microfluidic droplets and proof-of-principle reaction assessments with immobilized laccase},
  series = {Engineering in Life Sciences},
  volume    = {16},
  journal   = {Engineering in Life Sciences},
  number    = {3},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  doi       = {10.1002/elsc.201400124},
  pages     = {222 -- 230},
  year      = {2016},
  abstract  = {In the field of biotechnology and molecular biology, the use of small liquid volumes has significant advantages. In particular, screening and optimization runs with acceptable amounts of expensive and hardly available catalysts, reagents, or biomolecules are feasible with microfluidic technologies. The presented new microfluidic system is based on the inclusion of small liquid volumes by a protective shell of magnetizable microparticles. Hereby, discrete aqueous microreactor drops with volumes of 1-30 μL can be formed on a simple planar surface. A digital movement and manipulation of the microreactor is performed by overlapping magnetic forces. The magnetic forces are generated by an electrical coil matrix positioned below a glass plate. With the new platform technology, several discrete reaction compartments can be moved simultaneously on one surface. Due to the magnetic fields, the reactors can even be merged to initiate reactions by mixing or positioned above surface-immobilized catalysts and then opened by magnetic force. Comparative synthesis routes of the magnetizable shell particles and superhydrophobic glass slides including their performance and stability with the reaction platform are described. The influence of diffusive mass transport during the catalyzed reaction is discussed by evaluation finite element model of the microreactor. Furthermore, a first model dye reaction of the enzyme laccase has been established.},
  language  = {en}
}
@article{RothTippkoetter2016,
  author    = {Roth, Jasmine and Tippk{\"o}tter, Nils},
  title     = {Evaluation of lignocellulosic material for butanol production using enzymatic hydrolysate medium},
  series = {Cellulose Chemistry and Technology},
  volume    = {50},
  journal   = {Cellulose Chemistry and Technology},
  number    = {3-4},
  publisher = {Editura Academiei Romane},
  address   = {Bukarest},
  pages     = {405 -- 410},
  year      = {2016},
  abstract  = {Butanol is a promising gasoline additive and platform chemical that can be readily produced via acetone-butanolethanol (ABE) fermentation from pretreated lignocellulosic materials. This article examines lignocellulosic material from beech wood for ABE fermentation, using Clostridium acetobutylicum. First, the utilization of both C₅₋ (xylose) and C₆₋ (glucose) sugars as sole carbon source was investigated in static cultivation, using serum bottles and synthetic medium. The utilization of pentose sugar resulted in a solvent yield of 0.231 g·g_sugar⁻¹, compared to 0.262 g·g_sugar⁻¹ using hexose. Then, the Organosolv pretreated crude cellulose fibers (CF) were enzymatically decomposed, and the resulting hydrolysate medium was analyzed for inhibiting compounds (furans, organic acids, phenolics) and treated with ionexchangers for detoxification. Batch fermentation in a bioreactor using CF hydrolysate medium resulted in a total solvent yield of 0.20 gABE·g_sugar⁻¹.},
  language  = {en}
}
@article{RoeschKratzHeringetal.2016,
  author    = {R{\"o}sch, C. and Kratz, F. and Hering, T. and Trautmann, S. and Umanskaya, N. and Tippk{\"o}tter, Nils and M{\"u}ller-Renno, C.M. and Ulber, R. and Hannig, M. and Ziegler, C.},
  title     = {Albumin-lysozyme interactions: cooperative adsorption on titanium and enzymatic activity},
  series = {Colloids and Surfaces B: Biointerfaces},
  volume    = {149},
  journal   = {Colloids and Surfaces B: Biointerfaces},
  number    = {1},
  publisher = {Elsevier},
  address   = {Amsterdam},
  doi       = {10.1016/j.colsurfb.2016.09.048},
  pages     = {115 -- 121},
  year      = {2016},
  abstract  = {The interplay of albumin (BSA) and lysozyme (LYZ) adsorbed simultaneously on titanium was analyzed by gel electrophoresis and BCA assay. It was found that BSA and lysozyme adsorb cooperatively. Additionally, the isoelectric point of the respective protein influences the adsorption. Also, the enzymatic activity of lysozyme and amylase (AMY) in mixtures with BSA was considered with respect to a possible influence of protein-protein interaction on enzyme activity. Indeed, an increase of lysozyme activity in the presence of BSA could be observed. In contrast, BSA does not influence the activity of amylase.},
  language  = {en}
}
@article{HorbachDuongStaat2017,
  author    = {Horbach, Andreas and Duong, Minh Tuan and Staat, Manfred},
  title     = {Modelling of compressible and orthotropic surgical mesh implants based on optical deformation measurement},
  series = {Journal of the mechanical behavior of biomedical materials},
  volume    = {74},
  journal   = {Journal of the mechanical behavior of biomedical materials},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {1751-6161},
  doi       = {10.1016/j.jmbbm.2017.06.012},
  pages     = {400 -- 410},
  year      = {2017},
  language  = {en}
}
@article{MichaelMayerWeberetal.2017,
  author    = {Michael, Hackl and Mayer, Katharina and Weber, Mareike and Staat, Manfred and van Riet, Roger and Burkhart, Klau Josef and M{\"u}ller, Lars Peter and Wegmann, Kilian},
  title     = {Plate osteosynthesis of proximal ulna fractures : a biomechanical micromotion analysis},
  series = {The journal of hand surgery},
  volume    = {42},
  journal   = {The journal of hand surgery},
  number    = {10},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0363-5023},
  doi       = {10.1016/j.jhsa.2017.05.014},
  pages     = {834.e1 -- 834.e7},
  year      = {2017},
  language  = {en}
}
@article{PfaffEnning2017,
  author    = {Pfaff, Raphael and Enning, Manfred},
  title     = {G{\"u}terwagen 4.0 - Der G{\"u}terwagen f{\"u}r das Internet der Dinge. Teil 2: Ausgew{\"a}hlte technische Aspekte und Prozesse},
  series = {ETR - Eisenbahntechnische Rundschau},
  volume    = {66},
  journal   = {ETR - Eisenbahntechnische Rundschau},
  number    = {5},
  publisher = {DVV Media Group},
  address   = {Hamburg},
  issn      = {0013-2845},
  pages     = {74 -- 77},
  year      = {2017},
  language  = {de}
}
@article{PfaffSchmidt2016,
  author    = {Pfaff, Raphael and Schmidt, Bernd},
  title     = {Daten in der Cloud - und dann?},
  series = {Deine Bahn},
  journal   = {Deine Bahn},
  number    = {6},
  publisher = {Bahn-Fachverlag},
  address   = {Berlin},
  issn      = {0948-7263},
  pages     = {50 -- 55},
  year      = {2016},
  abstract  = {Schienenverkehrssysteme stehen in zunehmendem Wettbewerb, sowohl untereinander als auch mit anderen Verkehrstr{\"a}gern. Als wichtiger Aspekt zur Steigerung der Kosteneffizienz wird die Digitalisierung des Betriebs und der Fahrzeuge betrachtet. {\"U}ber eine Prognose der Ausfallwahrscheinlichkeit bzw. Restlebensdauer von Subsystemen k{\"o}nnen mittels Digitalisierung die Instandhaltungskosten gesenkt werden. Die geringen Fehlerraten im System Bahn machen die Nutzung besonderer Simulationstechniken notwendig. In diesem Beitrag wird gezeigt, wie sich die Subsystemverf{\"u}gbarkeit aus den beobachteten Fehlerraten der Teilfunktionen vorhersagen l{\"a}sst.},
  language  = {de}
}
@article{SchneiderSchneiderKinderetal.2017,
  author    = {Schneider, Wilhelm and Schneider, Bettina and Kinder, Stephanie and Meinhardt, Kerstin},
  title     = {Grundbegriffe der Abgabenordnung},
  series = {Das Wirtschaftsstudium : wisu ; Zeitschrift f{\"u}r Ausbildung, Examen, Berufseinstieg und Fortbildung},
  volume    = {46},
  journal   = {Das Wirtschaftsstudium : wisu ; Zeitschrift f{\"u}r Ausbildung, Examen, Berufseinstieg und Fortbildung},
  number    = {5},
  publisher = {Lange},
  address   = {D{\"u}sseldorf},
  issn      = {0340-3084},
  pages     = {575 -- 581},
  year      = {2017},
  language  = {de}
}
@article{YoshinobuMiyamotoWerneretal.2017,
  author    = {Yoshinobu, Tatsuo and Miyamoto, Ko-ichiro and Werner, Frederik and Poghossian, Arshak and Wagner, Torsten and Sch{\"o}ning, Michael Josef},
  title     = {Light-addressable potentiometric sensors for quantitative spatial imaging of chemical species},
  series = {Annual Review of Analytical Chemistry},
  volume    = {10},
  journal   = {Annual Review of Analytical Chemistry},
  publisher = {Annual Reviews},
  address   = {Palo Alto, Calif.},
  issn      = {1936-1327},
  doi       = {10.1146/annurev-anchem-061516-045158},
  pages     = {225 -- 246},
  year      = {2017},
  abstract  = {A light-addressable potentiometric sensor (LAPS) is a semiconductor-based chemical sensor, in which a measurement site on the sensing surface is defined by illumination. This light addressability can be applied to visualize the spatial distribution of pH or the concentration of a specific chemical species, with potential applications in the fields of chemistry, materials science, biology, and medicine. In this review, the features of this chemical imaging sensor technology are compared with those of other technologies. Instrumentation, principles of operation, and various measurement modes of chemical imaging sensor systems are described. The review discusses and summarizes state-of-the-art technologies, especially with regard to the spatial resolution and measurement speed; for example, a high spatial resolution in a submicron range and a readout speed in the range of several tens of thousands of pixels per second have been achieved with the LAPS. The possibility of combining this technology with microfluidic devices and other potential future developments are discussed.},
  language  = {en}
}
@article{SousaSiqueiraVerciketal.2017,
  author    = {Sousa, Marcos A. M. and Siqueira, Jose R. Jr. and Vercik, Andres and Sch{\"o}ning, Michael Josef and Oliveira, Osvaldo N. Jr.},
  title     = {Determining the optimized layer-by-layer film architecture with dendrimer/carbon nanotubes for field-effect sensors},
  series = {IEEE Sensors Journal},
  volume    = {17},
  journal   = {IEEE Sensors Journal},
  number    = {6},
  publisher = {IEEE},
  address   = {New York},
  issn      = {1558-1748},
  doi       = {10.1109/JSEN.2017.2653238},
  pages     = {1735 -- 1740},
  year      = {2017},
  abstract  = {The capacitive electrolyte-insulator-semiconductor (EIS) structure is a typical device based on a field-effect sensor platform. With a simple silicon-based structure, EIS have been useful for several sensing applications, especially with incorporation of nanostructured films to modulate the ionic transport and the flat-band potential. In this paper, we report on ion transport and changes in flat-band potential in EIS sensors made with layer-by-layer films containing poly(amidoamine) (PAMAM) dendrimer and single-walled carbon nanotubes (SWNTs) adsorbed on p-Si/SiO 2 /Ta 2 O 5 chips with an Al ohmic contact. The impedance spectra were fitted using an equivalent circuit model, from which we could determine parameters such as the double-layer capacitance. This capacitance decreased with the number of bilayers owing to space charge accumulated at the electrolyte-insulator interface, up to three PAMAM/SWNTs bilayers, after which it stabilized. The charge-transfer resistance was also minimum for three bilayers, thus indicating that this is the ideal architecture for an optimized EIS performance. The understanding of the influence of nanostructures and the fine control of operation parameters pave the way for optimizing the design and performance of new EIS sensors.},
  language  = {en}
}