@article{TippkoetterStueckmannKrolletal.2009,
  author    = {Tippk{\"o}tter, Nils and St{\"u}ckmann, Henning and Kroll, Stephen and Winkelmann, Gunda and Noack, Udo and Scheper, Thomas and Ulber, Roland},
  title     = {A semi-quantitative dipstick assay for microcystin},
  series = {Analytical and Bioanalytical Chemistry},
  volume    = {394},
  journal   = {Analytical and Bioanalytical Chemistry},
  number    = {3},
  publisher = {springer},
  address   = {Berlin},
  issn      = {1618-2650},
  doi       = {10.1007/s00216-009-2750-8},
  pages     = {863 -- 869},
  year      = {2009},
  abstract  = {An immunochromatographic lateral flow dipstick assay for the fast detection of microcystin-LR was developed. Colloid gold particles with diameters of 40 nm were used as red-colored antibody labels for the visual detection of the antigen. The new dipstick sensor is capable of detecting down to 5 µg·l-1 (ppb; total inversion of the color signal) or 1 ppb (observation of color grading) of microcystin-LR. The course of the labeling reaction was observed via spectrometric wave shifts caused by the change of particle size during the binding of antibodies. Different stabilizing reagents showed that especially bovine serum albumin (BSA) and casein increase the assays sensitivity and the conjugate stability. Performance of the dipsticks was quantified by pattern processing of capture zone CCD images. Storage stability of dipsticks and conjugate suspensions over 115 days under different conditions were monitored. The ready-to-use dipsticks were successfully tested with microcystin-LR-spiked samples of outdoor drinking- and salt water and applied to the tissue of microcystin-fed mussels.},
  language  = {en}
}
@article{TippkoetterWollnyKampeisetal.2011,
  author    = {Tippk{\"o}tter, Nils and Wollny, S. and Kampeis, P. and Oster, J. and Schneider, H. and Ulber, R.},
  title     = {Magnetseparation von Proteinen : Separation von Zielmolek{\"u}len durch hochselektive Aptamere},
  series = {GIT Labor-Fachzeitschrift},
  volume    = {55},
  journal   = {GIT Labor-Fachzeitschrift},
  number    = {10},
  publisher = {Wiley},
  address   = {Weinheim},
  pages     = {666},
  year      = {2011},
  abstract  = {Durch die Kombination von Oligonukleotid-Liganden (Aptameren) hoher Bindungsaffinit{\"a}ten mit hochselektiv abtrennbaren magnetisierbaren Mikropartikeln wird eine einstufige Separation von Zielmolek{\"u}len aus mikrobiologischen Produktionsans{\"a}tzen m{\"o}glich. Die Aptamere werden hierf{\"u}r reversibel auf den Partikeloberfl{\"a}chen gebunden und f{\"u}r die spezifische Isolierung von Bioprodukten eingesetzt. Die Abtrennung der beladenen Partikel erfolgt durch einen neuen Rotor-Stator-Separator mit Hochgradient-Magnetfeld.},
  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{UlberTippkoetterBuchholzetal.2008,
  author    = {Ulber, R. and Tippk{\"o}tter, Nils and Buchholz, H. and Demmer, W. and Scheper, T.},
  title     = {Innovative Verfahren in der Molkeaufarbeitung zur Gewinnung neuer Produkte},
  series = {Deutsche Milchwirtschaft},
  volume    = {59},
  journal   = {Deutsche Milchwirtschaft},
  number    = {19},
  issn      = {0012-0480},
  pages     = {704 -- 706},
  year      = {2008},
  language  = {de}
}
@article{UlberPothMonzonetal.2010,
  author    = {Ulber, Roland and Poth, Sebastian and Monzon, Magaly and Tippk{\"o}tter, Nils},
  title     = {Prozessintegration von Hydrolyse und Fermentation von Cellulose- Faserstoff},
  series = {Chemie Ingenieur Technik},
  volume    = {82},
  journal   = {Chemie Ingenieur Technik},
  number    = {1-2},
  issn      = {1522-2640},
  doi       = {10.1002/cite.200900103},
  pages     = {135 -- 139},
  year      = {2010},
  abstract  = {Ein viel versprechender erneuerbarer Rohstoff f{\"u}r die Produktion von Chemikalien und Treibstoffen ist Lignocellulose aus pflanzlicher Biomasse. Die darin enthaltenen Zucker k{\"o}nnen mittels enzymatischer Hydrolyse freigesetzt und fermentativ zu Ethanol umgesetzt werden. Ein interessanter Ansatz ist dabei die simultane Verzuckerung und Fermentation. Hefen und Enzyme haben mit 30 °C bzw. 50 °C zwar unterschiedliche Temperaturoptima, es konnte aber gezeigt werden, dass auch bei den niedrigeren Temperaturen eine Umsetzung der Cellulose zu Glucose erfolgt, wenn auch langsamer als bei optimalen Bedingungen. Außerdem konnte in Vorversuchen gezeigt werden, dass Ethanol in den zu erwartenden Konzentrationen keinen Einfluss auf die enzymatische Umsetzung hat.},
  language  = {de}
}
@article{UlberTippkoetter2009,
  author    = {Ulber, Roland and Tippk{\"o}tter, Nils},
  title     = {Nitratfreie Molke},
  series = {Rundschau f{\"u}r Fleischhygiene und Lebensmittel{\"u}berwachung},
  journal   = {Rundschau f{\"u}r Fleischhygiene und Lebensmittel{\"u}berwachung},
  number    = {4},
  pages     = {150 -- 152},
  year      = {2009},
  language  = {de}
}
@article{WiesenTippkoetterMuffleretal.2015,
  author    = {Wiesen, Sebastian and Tippk{\"o}tter, Nils and Muffler, Kai and Suck, Kirstin and Sohling, Ulrich and Ruf, Friedrich and Ulber, Roland},
  title     = {Adsorption of fatty acids to layered double hydroxides in aqueous systems},
  series = {Adsorption},
  volume    = {21},
  journal   = {Adsorption},
  number    = {6-7},
  publisher = {Springer},
  address   = {Berlin},
  pages     = {459 -- 466},
  year      = {2015},
  abstract  = {Due to their anion exchange characteristics, layered double hydroxides (LDHs) are suitable for the detoxification of aqueous, fatty acid containing fermentation substrates. The aim of this study is to examine the adsorption mechanism, using crude glycerol from plant oil esterification as a model system. Changes in the intercalation structure in relation to the amount of fatty acids adsorbed are monitored by X-ray diffraction and infra-red spectroscopy. Additionally, calcination of LDH is investigated in order to increase the binding capacity for fatty acids. Our data propose that, at ambient temperature, fatty acids can be bound to the hydrotalcite by adsorption or in addition by intercalation, depending on fatty acid concentration. The adsorption of fatty acids from crude glycerol shows a BET-like behavior. Above a fatty acid concentration of 3.5 g L-1, intercalation of fatty acids can be shown by the appearance of an increased interlayer spacing. This observation suggests a two phase adsorption process. Calcination of LDHs allows increasing the binding capacity for fatty acids by more than six times, mainly by reduction of structural CO32-.},
  language  = {en}
}
@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{WulfhorstDuweMerseburgetal.2016,
  author    = {Wulfhorst, Helene and Duwe, Anna-Maria and Merseburg, Johannes and Tippk{\"o}tter, Nils},
  title     = {Compositional analysis of pretreated (beech) wood using differential scanning calorimetry and multivariate data analysis},
  series = {Tetrahedron},
  volume    = {72},
  journal   = {Tetrahedron},
  number    = {46},
  publisher = {Elsevier},
  address   = {Amsterdam},
  doi       = {10.1016/j.tet.2016.04.029},
  pages     = {7329 -- 7334},
  year      = {2016},
  abstract  = {The composition of plant biomass varies depending on the feedstock and pre-treatment conditions and influences its processing in biorefineries. In order to ensure optimal process conditions, the quantitative proportion of the main polymeric components of the pre-treated biomass has to be determined. Current standard procedures for biomass compositional analysis are complex, the measurements are afflicted with errors and therefore often not comparable. Hence, new powerful analytical methods are urgently required to characterize biomass. In this contribution, Differential Scanning Calorimetry (DSC) was applied in combination with multivariate data analysis (MVA) to detect the cellulose content of the plant biomass pretreated by Liquid Hot Water (LHW) and Organosolv processes under various conditions. Unlike conventional techniques, the developed analytic method enables the accurate quantification of monosaccharide content of the plant biomass without any previous sample preparation. It is easy to handle and avoids errors in sample preparation.},
  language  = {en}
}