@article{LuetzowHommesSchattmannNeffeetal.2018,
  author    = {L{\"u}tzow, Karola and Hommes-Schattmann, Paul J. and Neffe, Axel T. and Ahmad, Bilal and Williams, Gareth R. and Lendlein, Andreas},
  title     = {Perfluorophenyl azide functionalization of electrospun poly(para-dioxanone)},
  series = {Polymers for advanced technologies},
  volume    = {30},
  journal   = {Polymers for advanced technologies},
  number    = {5},
  publisher = {Wiley},
  address   = {Hoboken},
  issn      = {1042-7147},
  doi       = {10.1002/pat.4331},
  pages     = {1165 -- 1172},
  year      = {2018},
  abstract  = {Strategies to surface-functionalize scaffolds by covalent binding of biologically active compounds are of fundamental interest to control the interactions between scaffolds and biomolecules or cells. Poly(para-dioxanone) (PPDO) is a clinically established polymer that has shown potential as temporary implant, eg, for the reconstruction of the inferior vena cava, as a nonwoven fiber mesh. However, PPDO lacks suitable chemical groups for covalent functionalization. Furthermore, PPDO is highly sensitive to hydrolysis, reflected by short in vivo half-life times and degradation during storage. Establishing a method for covalent functionalization without degradation of this hydrolyzable polymer is therefore important to enable the surface tailoring for tissue engineering applications. It was hypothesized that treatment of PPDO with an N-hydroxysuccinimide ester group bearing perfluorophenyl azide (PFPA) under UV irradiation would allow efficient surface functionalization of the scaffold. X-ray photoelectron spectroscopy and attenuated total reflectance Fourier-transformed infrared spectroscopy investigation revealed the successful binding, while a gel permeation chromatography study showed that degradation did not occur under these conditions. Coupling of a rhodamine dye to the N-hydroxysuccinimide esters on the surface of a PFPA-functionalized scaffold via its amine linker showed a homogenous staining of the PPDO in laser confocal microscopy. The PFPA method is therefore applicable even to the surface functionalization of hydrolytically labile polymers, and it was demonstrated that PFPA chemistry may serve as a versatile tool for the (bio-)functionalization of PPDO scaffolds.},
  language  = {en}
}
@article{CzarneckiWessig2018,
  author    = {Czarnecki, Maciej and Wessig, Pablo},
  title     = {Scaling Up UV-Mediated Intramolecular Photodehydro-Diels-Alder Reactions Using a Homemade High-Performance Annular Continuous-Flow Reactor},
  series = {Organic Process Research \& Development},
  volume    = {22},
  journal   = {Organic Process Research \& Development},
  number    = {12},
  publisher = {American Chemical Society},
  address   = {Washington},
  issn      = {1083-6160},
  doi       = {10.1021/acs.oprd.8b00353},
  pages     = {1823 -- 1827},
  year      = {2018},
  abstract  = {Here we present a self-made annular continuous-flow reactor that can be used in the UV/vis range in an internal numbering-up manner. As a model reaction, we chose a powerful batch-scale-limited benzoannelation method, namely, an intramolecular photodehydro-Diels-Alder (IMPDDA) reaction. The scale-up potential of this particular photochemical benchmark reaction toward the preparation of macrocylic (1,7)naphthalenophanes by variation of selected flow parameters is presented.},
  language  = {en}
}
@article{HoangMertensWessigetal.2018,
  author    = {Hoang, Hoa T. and Mertens, Monique and Wessig, Pablo and Sellrie, Frank and Schenk, J{\"o}rg A. and Kumke, Michael Uwe},
  title     = {Antibody Binding at the Liposome-Water Interface},
  series = {ACS Omega},
  volume    = {3},
  journal   = {ACS Omega},
  number    = {12},
  publisher = {American Chemical Society},
  address   = {Washington},
  issn      = {2470-1343},
  doi       = {10.1021/acsomega.8b03016},
  pages     = {18109 -- 18116},
  year      = {2018},
  abstract  = {Different signal amplification strategies to improve the detection sensitivity of immunoassays have been applied which utilize enzymatic reactions, nanomaterials, or liposomes. The latter are very attractive materials for signal amplification because liposomes can be loaded with a large amount of signaling molecules, leading to a high sensitivity. In addition, liposomes can be used as a cell-like "bioscaffold" to directly test recognition schemes aiming at cell-related processes. This study demonstrates an easy and fast approach to link the novel hydrophobic optical probe based on [1,3]dioxolo[4,5-f]-[1,3]benzodioxole (DBD dye mm239) with tunable optical properties to hydrophilic recognition elements (e.g., antibodies) using liposomes for signal amplification and as carrier of the hydrophobic dye. The fluorescence properties of mm239 (e.g., long fluorescence lifetime, large Stokes shift, high photostability, and high quantum yield), its high hydrophobicity for efficient anchoring in liposomes, and a maleimide bioreactive group were applied in a unique combination to build a concept for the coupling of antibodies or other protein markers to liposomes (coupling to membranes can be envisaged). The concept further allowed us to avoid multiple dye labeling of the antibody. Here, anti-TAMRA-antibody (DC7-Ab) was attached to the liposomes. In proof-of-concept, steady-state as well as time-resolved fluorescence measurements (e.g., fluorescence depolarization) in combination with single molecule detection (fluorescence correlation spectroscopy, FCS) were used to analyze the binding interaction between DC7-Ab and liposomes as well as the binding of the antigen rhodamine 6G (R6G) to the antibody. Here, the Forster resonance energy transfer (FRET) between mm239 and R6G was monitored. In addition to ensemble FRET data, single-molecule FRET (PIE-FRET) experiments using pulsed interleaved excitation were used to characterize in detail the binding on a single-molecule level to avoid averaging out effects.},
  language  = {en}
}
@article{SunDongOsenbergetal.2018,
  author    = {Sun, Fu and Dong, Kang and Osenberg, Markus and Hilger, Andre and Risse, Sebastian and Lu, Yan and Kamm, Paul H. and Klaus, Manuela and Markoetter, Henning and Garcia-Moreno, Francisco and Arlt, Tobias and Manke, Ingo},
  title     = {Visualizing the morphological and compositional evolution of the interface of InLi-anode|thio-LISION electrolyte in an all-solid-state Li-S cell by in operando synchrotron X-ray tomography and energy dispersive diffraction},
  series = {Journal of materials chemistry : A, Materials for energy and sustainability},
  volume    = {6},
  journal   = {Journal of materials chemistry : A, Materials for energy and sustainability},
  number    = {45},
  publisher = {Royal Society of Chemistry},
  address   = {Cambridge},
  issn      = {2050-7488},
  doi       = {10.1039/c8ta08821g},
  pages     = {22489 -- 22496},
  year      = {2018},
  abstract  = {Dynamic and direct visualization of interfacial evolution is helpful in gaining fundamental knowledge of all-solid-state-lithium battery working/degradation mechanisms and clarifying future research directions for constructing next-generation batteries. Herein, in situ and in operando synchrotron X-ray tomography and energy dispersive diffraction were simultaneously employed to record the morphological and compositional evolution of the interface of InLi-anode|sulfide-solid-electrolyte during battery cycling. Compelling morphological evidence of interfacial degradation during all-solid-state-lithium battery operation has been directly visualized by tomographic measurement. The accompanying energy dispersive diffraction results agree well with the observed morphological deterioration and the recorded electrochemical performance. It is concluded from the current investigation that a fundamental understanding of the phenomena occurring at the solid-solid electrode|electrolyte interface during all-solid-state-lithium battery cycling is critical for future progress in cell performance improvement and may determine its final commercial viability.},
  language  = {en}
}
@article{ZivanovicKochovskiArenzetal.2018,
  author    = {Zivanovic, Vesna and Kochovski, Zdravko and Arenz, Christoph and Lu, Yan and Kneipp, Janina},
  title     = {SERS and Cryo-EM Directly Reveal Different Liposome Structures during Interaction with Gold Nanoparticles},
  series = {The journal of physical chemistry letters},
  volume    = {9},
  journal   = {The journal of physical chemistry letters},
  number    = {23},
  publisher = {American Chemical Society},
  address   = {Washington},
  issn      = {1948-7185},
  doi       = {10.1021/acs.jpclett.8b03191},
  pages     = {6767 -- 6772},
  year      = {2018},
  abstract  = {The combination of gold nanoparticles with liposomes is important for nano- and biotechnology. Here, we present direct, label-free characterization of liposome structure and composition at the site of its interaction with citrate-stabilized gold nanoparticles by surface-enhanced Raman scattering (SERS) and cryogenic electron microscopy (cryo-EM). Evidenced by the vibrational spectra and cryo-EM, the gold nanoparticles destroy the bilayer structure of interacting liposomes in the presence of a high amount of citrate, while at lower citrate concentration the nanoparticles interact with the surface of the intact liposomes. The spectra of phosphatidylcholine and phosphatidylcholine/sphingomyelin liposomes show that at the site of interaction the lipid chains are in the gel phase. The SERS spectra indicate that cholesterol has strong effects on the contacts of the vesicles with the nanoparticles. By combining cryo-EM and SERS, the structure and properties of lipid nanoparticle composites could be tailored for the development of drug delivery systems.},
  language  = {en}
}
@article{SchultzeSchmidt2018,
  author    = {Schultze, Christiane and Schmidt, Bernd},
  title     = {Ring-closing-metathesis-based synthesis of annellated coumarins from 8-allylcoumarins},
  series = {Beilstein journal of organic chemistry},
  volume    = {14},
  journal   = {Beilstein journal of organic chemistry},
  publisher = {Beilstein-Institut zur F{\"o}rderung der Chemischen Wissenschaften},
  address   = {Frankfurt, Main},
  issn      = {1860-5397},
  doi       = {10.3762/bjoc.14.278},
  pages     = {2991 -- 2998},
  year      = {2018},
  abstract  = {8-Allylcoumarins are conveniently accessible through a microwave-promoted tandem Claisen rearrangement/Wittig olefination/cyclization sequence. They serve as a versatile platform for the annellation of five- to seven-membered rings using ring-closing olefin metathesis (RCM). Furano-, pyrano-, oxepino- and azepinocoumarins were synthesized from the same set of precursors using Ru-catalyzed double bond isomerizations and RCM in a defined order. One class of products, pyrano[2,3-f]chromene-2,8-diones, were inaccessible through direct RCM of an acrylate, but became available from the analogous allyl ether via an assisted tandem catalytic RCM/allylic oxidation sequence.},
  language  = {en}
}
@article{NguyenLeeAudoerschetal.2018,
  author    = {Nguyen, Hiep N. and Lee, Hyeunjoo and Aud{\"o}rsch, Stephan and Reznichenko, Alexander L. and Nawara-Hultzsch, Agnieszka J. and Schmidt, Bernd and Hultzsch, Kai C.},
  title     = {Asymmetric Intra- and Intermolecular Hydroamination Catalyzed by 3,3′-Bis(trisarylsilyl)- and 3,3′-Bis(arylalkylsilyl)-Substituted Binaphtholate Rare-Earth-Metal Complexes},
  series = {Organometallics},
  volume    = {37},
  journal   = {Organometallics},
  number    = {23},
  publisher = {American Chemical Society},
  address   = {Washington},
  issn      = {0276-7333},
  doi       = {10.1021/acs.organomet.8b00510},
  pages     = {4358 -- 4379},
  year      = {2018},
  abstract  = {The series of novel 3,3′-bis(trisarylsilyl)- and 3,3′-bis(arylalkylsilyl)-substituted binaphtholate rare-earth-metal complexes 2a-i (SiR3 = Si(o-biphenylene)Ph (a), SiCyPh2 (b), Si-t-BuPh2 (c), Si(i-Pr)3 (d), SiCy2Ph (e), Si(2-tolyl)Ph2 (f), Si(4-t-Bu-C6H4)3 (g), Si(4-MeO-C6H4)Ph2 (h), SiBnPh2 (i)) have been prepared via arene elimination from [Ln(o-C6H4CH2NMe2)3] (Ln = Y, Lu) and the corresponding 3,3′-bis(silyl)-substituted binaphthol. The complexes exhibit high catalytic activity in the hydroamination/cyclization of aminoalkenes, with activities exceeding 1000 h-1 for (R)-2f-Ln, (R)-2g-Ln, and (R)-2h-Ln in the cyclization of 2,2-diphenylpent-4-enylamine (3a) at 25 °C, while the rigid dibenzosilole-substituted complexes (R)-2a-Ln and the triisopropylsilyl-substituted complexes (R)-2d-Ln exhibited the lowest activity in the range of 150-270 h-1. Catalysts (R)-2b-Lu, (R)-2c-Lu, (R)-2f-Lu, and (R)-2i-Lu provide the highest selectivities for the majority of the substrates, while the yttrium congeners are usually less selective. The highest enantioselectivities of 96\% ee were observed using (R)-2a-Lu and (R)-2c-Lu in the cyclization of (4E)-2,2,5-triphenylpent-4-enylamine (9). The reactions show apparently zero-order rate dependence on substrate concentration and first-order rate dependence on catalyst concentration, with some reactions exhibiting a slightly accelerated rate at high conversion due to a shift in the equilibrium between a less active, higher coordinate catalyst species in favor of a more active, lower coordinate species as a result of weaker binding of the hydroamination product in comparison to the aminoalkene substrate. The shift in equilibrium from the higher to the lower coordinate species is also entropically favored at elevated temperatures, which results in an unusual increase in selectivity in the cyclization of 2,2-dimethylpent-4-enylamine (3d), presumably due to a higher selectivity of the lower coordinate catalyst species. All binaphtholate yttrium complexes, except (R)-2a-Y, are catalytically active in the intermolecular hydroamination of benzylamines with terminal alkenes. The highest selectivity of 66\% ee was observed for the reaction of benzylamine with 4-phenyl-1-butene using (R)-2h-Y at 110 °C.},
  language  = {en}
}
@article{ParamonovKlamrothLuetal.2018,
  author    = {Paramonov, Guennaddi K. and Klamroth, Tillmann and Lu, H. Z. and Bandrauk, Andre D.},
  title     = {Quantum dynamics, isotope effects, and power spectra of H-2(+) and HD+ excited to the continuum by strong one-cycle laser pulses: Three-dimensional non-Born-Oppenheimer simulations},
  series = {Physical review : A, Atomic, molecular, and optical physics},
  volume    = {98},
  journal   = {Physical review : A, Atomic, molecular, and optical physics},
  number    = {6},
  publisher = {American Physical Society},
  address   = {College Park},
  issn      = {2469-9926},
  doi       = {10.1103/PhysRevA.98.063431},
  pages     = {16},
  year      = {2018},
  abstract  = {Non-Born-Oppenheimer quantum dynamics of H-2(+) and HD+ excited by single one-cycle laser pulses linearly polarized along the molecular (z) axis have been studied within a three-dimensional model, including the internuclear distance R and electron coordinates z and rho, by means of the numerical solution of the time-dependent Schrodinger equation on the timescale of about 200 fs. Laser carrier frequencies corresponding to the wavelengths of lambda(l) = 400 and 50 nm have been used and the amplitudes of the pulses have been chosen such that the energies of H-2(+) and HD+ are above the dissociation threshold after the ends of the laser pulses. It is shown that excitation of H-2(+) and HD+ above the dissociation threshold is accompanied by formation of vibrationally "hot" and "cold" ensembles of molecules. Dissociation of vibrationally "hot" molecules does not prevent the appearance of post-laser-pulse electronic oscillations, parallel z oscillations, and transversal rho oscillations. Moreover, dissociation of "hot" molecules does not influence characteristic frequencies of electronic z and rho oscillations. The main difference between the laser-induced quantum dynamics of homonuclear H-2(+) and its heteronuclear isotope HD+ is that fast post-laser-pulse electronic z oscillations in H-2(+) are regularly shaped with the period of tau(shp) approximate to 30 fs corresponding to nuclear oscillations in H-2(+), while electronic z oscillations in HD+ arise as "echo pulses" of its initial excitation and appear with the period of tau(echo) approximate to 80 fs corresponding to nuclear motion in HD+. Accordingly, corresponding power spectra of nuclear motion contain strong low-frequency harmonics at omega(shp) = 2 pi/tau(shp) in H2(+) and omega(echo) = 2 pi/tau(echo) in HD+. Power spectra related to both electronic and nuclear motion have been calculated in the acceleration form. Both higher- and lower-order harmonics are generated at the laser wavelength lambda(l) = 400 nm, while only lower-order harmonics are well pronounced at lambda(l) = 50 nm. It is also shown that a rationalized harmonic order, defined in terms of the frequency of the laser-induced electronic z oscillations, agrees with the concept of inversion symmetry for electronic motion in diatomic molecules.},
  language  = {en}
}
@article{BalderasValadezEstevezEspinozaSalazarKurietal.2018,
  author    = {Balderas-Valadez, Ruth Fabiola and Estevez-Espinoza, J. O. and Salazar-Kuri, U. and Pacholski, Claudia and Mochan, Wolf Luis and Agarwal, Vivechana},
  title     = {Fabrication of ordered tubular porous silicon structures by colloidal lithography and metal assisted chemical etching},
  series = {Applied surface science : a journal devoted to applied physics and chemistry of surfaces and interfaces},
  volume    = {462},
  journal   = {Applied surface science : a journal devoted to applied physics and chemistry of surfaces and interfaces},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0169-4332},
  doi       = {10.1016/j.apsusc.2018.08.120},
  pages     = {783 -- 790},
  year      = {2018},
  abstract  = {Fabrication of well-ordered porous silicon tubular structures using colloidal lithography and metal assisted chemical etching is reported. A continuous hexagonal hole/particle gold pattern was designed over monocrystalline silicon through deposition of polyNIPAM microspheres, followed by the surface decoration with gold nanoparticles and thermal treatment. An etching reaction with HF, ethanol and H2O2 dissolved the silicon in contact with the metal nanoparticles (NP), creating a porous tubular array in the "off-metal area". The morphological characterization revealed the formation of a cylindrical hollow porous tubular shape with external and internal diameter of approx. 900 nm and 400 nm respectively, though it can be tuned to other desired sizes by choosing an appropriate dimension for the microspheres. The porous morphology and optical properties were studied as a function of resistivity of silicon substrates. Compared to two different gold templates on cSi and nontubular porous pillar structures, porous silicon tubular framework revealed a maximum surface enhanced Raman scattering enhancement factor of 10(6) for the detection of 6-mercaptopurine (6-MP). Due to the large surface area available for any surface modification, open nanostructured platforms such as those studied here have potential applications in the field of reflection/photoluminescene and SERS based optical bio-/chemical sensors.},
  language  = {en}
}
@article{AbbasVranicHoffmannetal.2018,
  author    = {Abbas, Ioana M. and Vranic, Marija and Hoffmann, Holger and El-Khatib, Ahmed H. and Montes-Bay{\´o}n, Mar{\´i}a and M{\"o}ller, Heiko Michael and Weller, Michael G.},
  title     = {Investigations of the Copper Peptide Hepcidin-25 by LC-MS/MS and NMR⁺},
  series = {International Journal of Molecular Sciences},
  volume    = {19},
  journal   = {International Journal of Molecular Sciences},
  number    = {8},
  publisher = {Molecular Diversity Preservation International},
  address   = {Basel},
  issn      = {1422-0067},
  doi       = {10.3390/ijms19082271},
  pages     = {16},
  year      = {2018},
  abstract  = {Hepcidin-25 was identified as themain iron regulator in the human body, and it by binds to the sole iron-exporter ferroportin. Studies showed that the N-terminus of hepcidin is responsible for this interaction, the same N-terminus that encompasses a small copper(II) binding site known as the ATCUN (amino-terminal Cu(II)- and Ni(II)-binding) motif. Interestingly, this copper-binding property is largely ignored in most papers dealing with hepcidin-25. In this context, detailed investigations of the complex formed between hepcidin-25 and copper could reveal insight into its biological role. The present work focuses on metal-bound hepcidin-25 that can be considered the biologically active form. The first part is devoted to the reversed-phase chromatographic separation of copper-bound and copper-free hepcidin-25 achieved by applying basic mobile phases containing 0.1\% ammonia. Further, mass spectrometry (tandemmass spectrometry (MS/MS), high-resolutionmass spectrometry (HRMS)) and nuclear magnetic resonance (NMR) spectroscopy were employed to characterize the copper-peptide. Lastly, a three-dimensional (3D)model of hepcidin-25with bound copper(II) is presented. The identification of metal complexes and potential isoforms and isomers, from which the latter usually are left undetected by mass spectrometry, led to the conclusion that complementary analytical methods are needed to characterize a peptide calibrant or referencematerial comprehensively. Quantitative nuclear magnetic resonance (qNMR), inductively-coupled plasma mass spectrometry (ICP-MS), ion-mobility spectrometry (IMS) and chiral amino acid analysis (AAA) should be considered among others.},
  language  = {en}
}