@article{CapitainRossJonesMoehringetal.2020,
  author    = {Capitain, Charlotte and Ross-Jones, Jesse and M{\"o}hring, Sophie and Tippk{\"o}tter, Nils},
  title     = {Differential scanning calorimetry for quantification of polymer biodegradability in compost},
  series = {International Biodeterioration \& Biodegradation},
  volume    = {149},
  journal   = {International Biodeterioration \& Biodegradation},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0964-8305},
  doi       = {10.1016/j.ibiod.2020.104914},
  pages     = {In Press, Article number 104914},
  year      = {2020},
  abstract  = {The objective of this study is the establishment of a differential scanning calorimetry (DSC) based method for online analysis of the biodegradation of polymers in complex environments. Structural changes during biodegradation, such as an increase in brittleness or crystallinity, can be detected by carefully observing characteristic changes in DSC profiles. Until now, DSC profiles have not been used to draw quantitative conclusions about biodegradation. A new method is presented for quantifying the biodegradation using DSC data, whereby the results were validated using two reference methods. The proposed method is applied to evaluate the biodegradation of three polymeric biomaterials: polyhydroxybutyrate (PHB), cellulose acetate (CA) and Organosolv lignin. The method is suitable for the precise quantification of the biodegradability of PHB. For CA and lignin, conclusions regarding their biodegradation can be drawn with lower resolutions. The proposed method is also able to quantify the biodegradation of blends or composite materials, which differentiates it from commonly used degradation detection methods.},
  language  = {en}
}
@article{WardoyoNoorElbersetal.2020,
  author    = {Wardoyo, Arinto Y.P. and Noor, Johan A.E. and Elbers, Gereon and Schmitz, Sandra and Flaig, Sascha T. and Budianto, Arif},
  title     = {Characterizing volcanic ash elements from the 2015 eruptions of bromo and raung volcanoes, Indonesia},
  series = {Polish Journal of Environmental Studies},
  volume    = {29},
  journal   = {Polish Journal of Environmental Studies},
  number    = {2},
  publisher = {HARD},
  address   = {Olsztyn},
  issn      = {2083-5906},
  doi       = {10.15244/pjoes/99101},
  pages     = {1899 -- 1907},
  year      = {2020},
  abstract  = {The volcanic eruptions of Mt. Bromo and Mt. Raung in East Java, Indonesia, in 2015 perturbed volcanic materials and affected surface-layer air quality at surrounding locations. During the episodes, the volcanic ash from the eruptions influenced visibility, traffic accidents, flight schedules, and human health. In this research, the volcanic ash particles were collected and characterized by relying on the detail of physical observation. We performed an assessment of the volcanic ash elements to characterize the volcanic ash using two different methods which are aqua regia extracts followed by MP-AES and XRF laboratory test of bulk samples. The analysis results showed that the volcanic ash was mixed of many materials, such as Al, Si, P, K, Ca, Ti, V, Cr, Mn, Fe, Ni, and others. Fe, Si, Ca, and Al were found as the major elements, while the others were the trace elements Ba, Cr, Cu, Mn, P, Mn, Ni, Zn, Sb, Sr, and V with the minor concentrations. XRF analyses showed that Fe dominated the elements of the volcanic ash. The XRF analysis showed that Fe was at 35.40\% in Bromo and 43.00\% in Raung of the detected elements in bulk material. The results of aqua regia extracts analyzed by MP-AES were 1.80\% and 1.70\% of Fe element for Bromo and Raung volcanoes, respectively.},
  language  = {en}
}
@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}
}
@article{MonakhovaDiehl2022,
  author    = {Monakhova, Yulia and Diehl, Bernd W.K.},
  title     = {Nuclear magnetic resonance spectroscopy as an elegant tool for a complete quality control of crude heparin material},
  series = {Journal of Pharmaceutical and Biomedical Analysis},
  volume    = {219},
  journal   = {Journal of Pharmaceutical and Biomedical Analysis},
  number    = {Article number: 114915},
  publisher = {Elsevier},
  address   = {New York, NY},
  issn      = {0731-7085},
  doi       = {10.1016/j.jpba.2022.114915},
  year      = {2022},
  abstract  = {Nuclear magnetic resonance (NMR) spectrometric methods for the quantitative analysis of pure heparin in crude heparin is proposed. For quantification, a two-step routine was developed using a USP heparin reference sample for calibration and benzoic acid as an internal standard. The method was successfully validated for its accuracy, reproducibility, and precision. The methodology was used to analyze 20 authentic porcine heparinoid samples having heparin content between 4.25 w/w \% and 64.4 w/w \%. The characterization of crude heparin products was further extended to a simultaneous analysis of these common ions: sodium, calcium, acetate and chloride. A significant, linear dependence was found between anticoagulant activity and assayed heparin content for thirteen heparinoids samples, for which reference data were available. A Diffused-ordered NMR experiment (DOSY) can be used for qualitative analysis of specific glycosaminoglycans (GAGs) in heparinoid matrices and, potentially, for quantitative prediction of molecular weight of GAGs. NMR spectrometry therefore represents a unique analytical method suitable for the simultaneous quantitative control of organic and inorganic composition of crude heparin samples (especially heparin content) as well as an estimation of other physical and quality parameters (molecular weight, animal origin and activity).},
  language  = {en}
}
@article{FalkenbergRahbaFischeretal.2022,
  author    = {Falkenberg, Fabian and Rahba, Jade and Fischer, David and Bott, Michael and Bongaerts, Johannes and Siegert, Petra},
  title     = {Biochemical characterization of a novel oxidatively stable, halotolerant, and high-alkaline subtilisin from Alkalihalobacillus okhensis Kh10-101T},
  series = {FEBS Open Bio},
  volume    = {12},
  journal   = {FEBS Open Bio},
  number    = {10},
  publisher = {Wiley},
  address   = {Hoboken, NJ},
  issn      = {2211-5463},
  doi       = {10.1002/2211-5463.13457},
  pages     = {1729 -- 1746},
  year      = {2022},
  abstract  = {Halophilic and halotolerant microorganisms represent a promising source of salt-tolerant enzymes suitable for various biotechnological applications where high salt concentrations would otherwise limit enzymatic activity. Considering the current growing enzyme market and the need for more efficient and new biocatalysts, the present study aimed at the characterization of a high-alkaline subtilisin from Alkalihalobacillus okhensis Kh10-101T. The protease gene was cloned and expressed in Bacillus subtilis DB104. The recombinant protease SPAO with 269 amino acids belongs to the subfamily of high-alkaline subtilisins. The biochemical characteristics of purified SPAO were analyzed in comparison with subtilisin Carlsberg, Savinase, and BPN'. SPAO, a monomer with a molecular mass of 27.1 kDa, was active over a wide range of pH 6.0-12.0 and temperature 20-80 °C, optimally at pH 9.0-9.5 and 55 °C. The protease is highly oxidatively stable to hydrogen peroxide and retained 58\% of residual activity when incubated at 10 °C with 5\% (v/v) H2O2 for 1 h while stimulated at 1\% (v/v) H2O2. Furthermore, SPAO was very stable and active at NaCl concentrations up to 5.0 m. This study demonstrates the potential of SPAO for biotechnological applications in the future.},
  language  = {en}
}
@article{LindnerBurgerRutledgeetal.2022,
  author    = {Lindner, Simon and Burger, Ren{\´e} and Rutledge, Douglas N. and Do, Xuan Tung and Rumpf, Jessica and Diehl, Bernd W. K. and Schulze, Margit and Monakhova, Yulia},
  title     = {Is the calibration transfer of multivariate calibration models between high- and low-field NMR instruments possible? A case study of lignin molecular weight},
  series = {Analytical chemistry},
  volume    = {94},
  journal   = {Analytical chemistry},
  number    = {9},
  publisher = {ACS Publications},
  address   = {Washington, DC},
  isbn      = {1520-6882},
  doi       = {10.1021/acs.analchem.1c05125},
  pages     = {3997 -- 4004},
  year      = {2022},
  abstract  = {Although several successful applications of benchtop nuclear magnetic resonance (NMR) spectroscopy in quantitative mixture analysis exist, the possibility of calibration transfer remains mostly unexplored, especially between high- and low-field NMR. This study investigates for the first time the calibration transfer of partial least squares regressions [weight average molecular weight (Mw) of lignin] between high-field (600 MHz) NMR and benchtop NMR devices (43 and 60 MHz). For the transfer, piecewise direct standardization, calibration transfer based on canonical correlation analysis, and transfer via the extreme learning machine auto-encoder method are employed. Despite the immense resolution difference between high-field and low-field NMR instruments, the results demonstrate that the calibration transfer from high- to low-field is feasible in the case of a physical property, namely, the molecular weight, achieving validation errors close to the original calibration (down to only 1.2 times higher root mean square errors). These results introduce new perspectives for applications of benchtop NMR, in which existing calibrations from expensive high-field instruments can be transferred to cheaper benchtop instruments to economize.},
  language  = {en}
}
@article{MonakhovaDiehl2022,
  author    = {Monakhova, Yulia and Diehl, Bernd W.K.},
  title     = {Multinuclear NMR screening of pharmaceuticals using standardization by 2H integral of a deuterated solvent},
  series = {Journal of Pharmaceutical and Biomedical Analysis},
  volume    = {209},
  journal   = {Journal of Pharmaceutical and Biomedical Analysis},
  number    = {Article number: 114530},
  publisher = {Elsevier},
  isbn      = {0731-7085},
  doi       = {10.1016/j.jpba.2021.114530},
  year      = {2022},
  abstract  = {NMR standardization approach that uses the 2H integral of deuterated solvent for quantitative multinuclear analysis of pharmaceuticals is described. As a proof of principle, the existing NMR procedure for the analysis of heparin products according to US Pharmacopeia monograph is extended to the determination of Na+ and Cl- content in this matrix. Quantification is performed based on the ratio of a 23Na (35Cl) NMR integral and 2H NMR signal of deuterated solvent, D2O, acquired using the specific spectrometer hardware. As an alternative, the possibility of 133Cs standardization using the addition of Cs2CO3 stock solution is shown. Validation characteristics (linearity, repeatability, sensitivity) are evaluated. A holistic NMR profiling of heparin products can now also be used for the quantitative determination of inorganic compounds in a single analytical run using a single sample. In general, the new standardization methodology provides an appealing alternative for the NMR screening of inorganic and organic components in pharmaceutical products.},
  language  = {en}
}
@article{BurgerLindnerRumpfetal.2022,
  author    = {Burger, Ren{\´e} and Lindner, Simon and Rumpf, Jessica and Do, Xuan Tung and Diehl, Bernd W.K. and Rehahn, Matthias and Monakhova, Yulia and Schulze, Margit},
  title     = {Benchtop versus high field NMR: Comparable performance found for the molecular weight determination of lignin},
  series = {Journal of Pharmaceutical and Biomedical Analysis},
  volume    = {212},
  journal   = {Journal of Pharmaceutical and Biomedical Analysis},
  number    = {Article number: 114649},
  publisher = {Elsevier},
  address   = {New York, NY},
  isbn      = {0731-7085},
  doi       = {10.1016/j.jpba.2022.114649},
  year      = {2022},
  abstract  = {Lignin is a promising renewable biopolymer being investigated worldwide as an environmentally benign substitute of fossil-based aromatic compounds, e.g. for the use as an excipient with antioxidant and antimicrobial properties in drug delivery or even as active compound. For its successful implementation into process streams, a quick, easy, and reliable method is needed for its molecular weight determination. Here we present a method using 1H spectra of benchtop as well as conventional NMR systems in combination with multivariate data analysis, to determine lignin's molecular weight (Mw and Mn) and polydispersity index (PDI). A set of 36 organosolv lignin samples (from Miscanthus x giganteus, Paulownia tomentosa and Silphium perfoliatum) was used for the calibration and cross validation, and 17 samples were used as external validation set. Validation errors between 5.6\% and 12.9\% were achieved for all parameters on all NMR devices (43, 60, 500 and 600 MHz). Surprisingly, no significant difference in the performance of the benchtop and high-field devices was found. This facilitates the application of this method for determining lignin's molecular weight in an industrial environment because of the low maintenance expenditure, small footprint, ruggedness, and low cost of permanent magnet benchtop NMR systems.},
  language  = {en}
}
@article{MonakhovaSobolevaFedotovaetal.2022,
  author    = {Monakhova, Yulia and Soboleva, Polina M. and Fedotova, Elena S. and Musina, Kristina T. and Burmistrova, Natalia A.},
  title     = {Quantum chemical calculations of IR spectra of heparin disaccharide subunits},
  series = {Computational and Theoretical Chemistry},
  volume    = {1217},
  journal   = {Computational and Theoretical Chemistry},
  number    = {Article number: 113891},
  publisher = {Elsevier},
  address   = {New York, NY},
  isbn      = {2210-271X},
  doi       = {10.1016/j.comptc.2022.113891},
  year      = {2022},
  abstract  = {Heparin is a natural polysaccharide, which plays essential role in many biological processes. Alterations in building blocks can modify biological roles of commercial heparin products, due to significant changes in the conformation of the polymer chain. The variability structure of heparin leads to difficulty in quality control using different analytical methods, including infrared (IR) spectroscopy. In this paper molecular modelling of heparin disaccharide subunits was performed using quantum chemistry. The structural and spectral parameters of these disaccharides have been calculated using RHF/6-311G. In addition, over-sulphated chondroitin sulphate disaccharide was studied as one of the most widespread contaminants of heparin. Calculated IR spectra were analyzed with respect to specific structure parameters. IR spectroscopic fingerprint was found to be sensitive to substitution pattern of disaccharide subunits. Vibrational assignments of calculated spectra were correlated with experimental IR spectral bands of native heparin. Chemometrics was used to perform multivariate analysis of simulated spectral data.},
  language  = {en}
}
@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}
}