@article{HafidiElHatkaSchmitzetal.2024,
  author    = {Hafidi, Youssef and El Hatka, Hicham and Schmitz, Dominik and Krauss, Manuel and Pettrak, J{\"u}rgen and Biel, Markus and Ittobane, Najim},
  title     = {Sustainable soil additives for water and micronutrient supply: swelling and chelating properties of polyaspartic acid hydrogels utilizing newly developed crosslinkers},
  series = {Gels},
  volume    = {10},
  journal   = {Gels},
  number    = {3},
  publisher = {MDPI},
  address   = {Basel},
  issn      = {2310-2861},
  doi       = {10.3390/gels10030170},
  pages     = {Artikel 170},
  year      = {2024},
  abstract  = {Drought and water shortage are serious problems in many arid and semi-arid regions. This problem is getting worse and even continues in temperate climatic regions due to climate change. To address this problem, the use of biodegradable hydrogels is increasingly important for the application as water-retaining additives in soil. Furthermore, efficient (micro-)nutrient supply can be provided by the use of tailored hydrogels. Biodegradable polyaspartic acid (PASP) hydrogels with different available (1,6-hexamethylene diamine (HMD) and L-lysine (LYS)) and newly developed crosslinkers based on diesters of glycine (GLY) and (di-)ethylene glycol (DEG and EG, respectively) were synthesized and characterized using Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM) and regarding their swelling properties (kinetic, absorbency under load (AUL)) as well as biodegradability of PASP hydrogel. Copper (II) and zinc (II), respectively, were loaded as micronutrients in two different approaches: in situ with crosslinking and subsequent loading of prepared hydrogels. The results showed successful syntheses of di-glycine-ester-based crosslinkers. Hydrogels with good water-absorbing properties were formed. Moreover, the developed crosslinking agents in combination with the specific reaction conditions resulted in higher water absorbency with increased crosslinker content used in synthesis (10\% vs. 20\%). The prepared hydrogels are candidates for water-storing soil additives due to the biodegradability of PASP, which is shown in an exemple. The incorporation of Cu(II) and Zn(II) ions can provide these micronutrients for plant growth.},
  language  = {en}
}
@techreport{TippkoetterWagner2019,
  author    = {Tippk{\"o}tter, Nils and Wagner, Sebastian},
  title     = {Biomimetischer Klebstoff aus ligninhaltigen Pflanzenresten (Teilvorhaben 1 und 2) : Schlussbericht zum Vorhaben : Laufzeit: 01.01.2016 bis 31.03.2019},
  publisher = {FH Aachen},
  address   = {J{\"u}lich},
  doi       = {10.2314/KXP:169732777X},
  pages     = {109 S.},
  year      = {2019},
  language  = {de}
}
@article{CapitainWagnerHummeletal.2021,
  author    = {Capitain, Charlotte and Wagner, Sebastian and Hummel, Joana and Tippk{\"o}tter, Nils},
  title     = {Investigation of C-N Formation Between Catechols and Chitosan for the Formation of a Strong, Novel Adhesive Mimicking Mussel Adhesion},
  series = {Waste and Biomass Valorization},
  volume    = {12},
  journal   = {Waste and Biomass Valorization},
  publisher = {Springer Nature},
  address   = {Cham},
  issn      = {1877-265X},
  doi       = {10.1007/s12649-020-01110-5},
  pages     = {1761 -- 1779},
  year      = {2021},
  language  = {en}
}
@inproceedings{WulfhorstMerseburgTippkoetter2015,
  author    = {Wulfhorst, Helene and Merseburg, Johannes and Tippk{\"o}tter, Nils},
  title     = {Analyse von Lignocellulose mittels dynamischer Differenzkalorimetrie und Infrarot - Spektrometrie},
  series = {12. Dresdner Sensor-Symposium 2015 2015-12-07 - 2015-12-09},
  booktitle = {12. Dresdner Sensor-Symposium 2015 2015-12-07 - 2015-12-09},
  isbn      = {978-3-9813484-9-1},
  doi       = {10.5162/12dss2015/P6.2},
  pages     = {210 -- 215},
  year      = {2015},
  language  = {de}
}
@misc{StadtmuellerTippkoetterUlber2015,
  author    = {Stadtm{\"u}ller, Ralf and Tippk{\"o}tter, Nils and Ulber, Roland},
  title     = {Method for production of single-stranded macronucleotides},
  year      = {2015},
  abstract  = {The invention relates to a method for production of single-stranded macronucleotides by amplifying and ligating an extended monomeric single-stranded target nucleic acid sequence (targetss) into a repetitive cluster of double-stranded target nucleic acid sequences (targetds), and subsequently cloning the construct into a vector (aptagene vector). The aptagene vector is transformed into host cells for replication of the aptagene and isolated in order to optain single-stranded target sequences (targetss). The invention also relates to single-stranded nucleic acids, produced by a method of the invention.},
  language  = {en}
}
@misc{HuschyarTippkoetterUlber2015,
  author    = {Huschyar, Al-Kaidy and Tippk{\"o}tter, Nils and Ulber, Roland},
  title     = {System und Verfahren zur Durchf{\"u}hrung von chemischen, biologischen oder physikalischen Reaktionen},
  year      = {2015},
  language  = {de}
}
@misc{AlKaidyTippkoetterUlber2016,
  author    = {Al-Kaidy, Huschyar and Tippk{\"o}tter, Nils and Ulber, Roland},
  title     = {Vorrichtung und Verfahren zur Bestimmung des Kontaktwinkels eines Fl{\"u}ssigk{\"o}rpers mit einer Festk{\"o}rperoberfl{\"a}che},
  year      = {2016},
  abstract  = {Die vorliegende Erfindung betrifft eine Vorrichtung und ein Verfahren zur Bestimmung des Kontaktwinkels eines fl{\"u}ssigen oder mit Fl{\"u}ssigkeit gef{\"u}llten K{\"o}rpers. Dieser besteht aus einem Tr{\"a}ger (1) und einer damit verbundenen, in einem Winkelbereich von mehr als 0 ° bis maximal 90 ° neigbaren Ebene (8) mit einer darin ausgebildeten Abrollbahn (9) f{\"u}r den fl{\"u}ssigen oder mit Fl{\"u}ssigkeit gef{\"u}llten K{\"o}rper. An der Ebene (8) sind mehrere Sensoren (11,12) zur Erfassung der Rolldauer des K{\"o}rpers entlang der Rollstrecke angeordnet. Erfindungsgem{\"a}ß ist vorgesehen, dass die Einstellung des Neigungswinkels der Ebene (8) {\"u}ber ein Winkelmessger{\"a}t (10) erfolgt, wodurch ein Abrollwinkel erfassbar ist, bei dem der K{\"o}rper in Bewegung ger{\"a}t. Aus der Rolldauer, der Rollstrecke und dem Abrollwinkel wird der Kontaktwinkel des K{\"o}rpers ermittelt.},
  language  = {de}
}
@article{MonakhovaDiehl2021,
  author    = {Monakhova, Yulia and Diehl, Bernd W.K.},
  title     = {Novel approach of qNMR workflow by standardization using 2H integral: Application to any intrinsic calibration standard},
  series = {Talanta},
  volume    = {222},
  journal   = {Talanta},
  number    = {Article number: 121504},
  publisher = {Elsevier},
  isbn      = {0039-9140},
  doi       = {10.1016/j.talanta.2020.121504},
  year      = {2021},
  abstract  = {Quantitative nuclear magnetic resonance (qNMR) is routinely performed by the internal or external standardization. The manuscript describes a simple alternative to these common workflows by using NMR signal of another active nuclei of calibration compound. For example, for any arbitrary compound quantification by NMR can be based on the use of an indirect concentration referencing that relies on a solvent having both 1H and 2H signals. To perform high-quality quantification, the deuteration level of the utilized deuterated solvent has to be estimated. In this contribution the new method was applied to the determination of deuteration levels in different deuterated solvents (MeOD, ACN, CDCl3, acetone, benzene, DMSO-d6). Isopropanol-d6, which contains a defined number of deuterons and protons, was used for standardization. Validation characteristics (precision, accuracy, robustness) were calculated and the results showed that the method can be used in routine practice. Uncertainty budget was also evaluated. In general, this novel approach, using standardization by 2H integral, benefits from reduced sample preparation steps and uncertainties, and can be applied in different application areas (purity determination, forensics, pharmaceutical analysis, etc.).},
  language  = {en}
}
@article{BurmistrovaSobolevaMonakhova2021,
  author    = {Burmistrova, Natalia A. and Soboleva, Polina M. and Monakhova, Yulia},
  title     = {Is infrared spectroscopy combined with multivariate analysis a promising tool for heparin authentication?},
  series = {Journal of Pharmaceutical and Biomedical Analysis},
  volume    = {194},
  journal   = {Journal of Pharmaceutical and Biomedical Analysis},
  number    = {Article number: 113811},
  publisher = {Elsevier},
  address   = {Amsterdam},
  isbn      = {0731-7085},
  doi       = {10.1016/j.jpba.2020.113811},
  year      = {2021},
  abstract  = {The investigation of the possibility to determine various characteristics of powder heparin (n = 115) was carried out with infrared spectroscopy. The evaluation of heparin samples included several parameters such as purity grade, distributing company, animal source as well as heparin species (i.e. Na-heparin, Ca-heparin, and heparinoids). Multivariate analysis using principal component analysis (PCA), soft independent modelling of class analogy (SIMCA), and partial least squares - discriminant analysis (PLS-DA) were applied for the modelling of spectral data. Different pre-processing methods were applied to IR spectral data; multiplicative scatter correction (MSC) was chosen as the most relevant. Obtained results were confirmed by nuclear magnetic resonance (NMR) spectroscopy. Good predictive ability of this approach demonstrates the potential of IR spectroscopy and chemometrics for screening of heparin quality. This approach, however, is designed as a screening tool and is not considered as a replacement for either of the methods required by USP and FDA.},
  language  = {en}
}
@article{MonakhovaDiehl2021,
  author    = {Monakhova, Yulia and Diehl, Bernd W. K.},
  title     = {Simplification of NMR Workflows by Standardization Using 2H Integral of Deuterated Solvent as Applied to Aloe vera Preparations},
  series = {Applied Magnetic Resonance},
  volume    = {52},
  journal   = {Applied Magnetic Resonance},
  number    = {11},
  publisher = {Springer},
  address   = {Cham},
  issn      = {1613-7507},
  doi       = {10.1007/s00723-021-01393-4},
  pages     = {1591 -- 1600},
  year      = {2021},
  abstract  = {In this study, a recently proposed NMR standardization approach by 2H integral of deuterated solvent for quantitative multicomponent analysis of complex mixtures is presented. As a proof of principle, the existing NMR routine for the analysis of Aloe vera products was modified. Instead of using absolute integrals of targeted compounds and internal standard (nicotinamide) from 1H-NMR spectra, quantification was performed based on the ratio of a particular 1H-NMR compound integral and 2H-NMR signal of deuterated solvent D2O. Validation characteristics (linearity, repeatability, accuracy) were evaluated and the results showed that the method has the same precision as internal standardization in case of multicomponent screening. Moreover, a dehydration process by freeze drying is not necessary for the new routine. Now, our NMR profiling of A. vera products needs only limited sample preparation and data processing. The new standardization methodology provides an appealing alternative for multicomponent NMR screening. In general, this novel approach, using standardization by 2H integral, benefits from reduced sample preparation steps and uncertainties, and is recommended in different application areas (purity determination, forensics, pharmaceutical analysis, etc.).},
  language  = {en}
}