TY - JOUR A1 - Grunwald, M. A. A1 - Hagenlocher, S. E. A1 - Turkanovic, L. A1 - Bauch, S. M. A1 - Wachsmann, S. B. A1 - Altevogt, L. A. A1 - Ebert, M. A1 - Knöller, J. A. A1 - Raab, A. R. A1 - Schulz, F. A1 - Kolmangadi, Mohamed A. A1 - Zens, A. A1 - Huber, P. A1 - Schönhals, Andreas A1 - Bilitiewski, U. A1 - Laschat, S. T1 - Does thermotropic liquid crystalline self-assembly control biological activity in amphiphilic amino acids? – tyrosine ILCs as a case study N2 - Amphiphilic amino acids represent promising scaffolds for biologically active soft matter. In order to understand the bulk self-assembly of amphiphilic amino acids into thermotropic liquid crystalline phases and their biological properties a series of tyrosine ionic liquid crystals (ILCs) was synthesized, carrying a benzoate unit with 0–3 alkoxy chains at the tyrosine unit and a cationic guanidinium head group. Investigation of the mesomorphic properties by polarizing optical microscopy (POM), differential scanning calorimetry (DSC) and X-ray diffraction (WAXS, SAXS) revealed smectic A bilayers (SmAd) for ILCs with 4-alkoxy- and 3,4-dialkoxybenzoates, whereas ILCs with 3,4,5-trisalkoxybenzoates showed hexagonal columnar mesophases (Colh ), while different counterions had only a minor influence. Dielectric measurements revealed a slightly higher dipole moment of non-mesomorphic tyrosine-benzoates as compared to their mesomorphic counterparts. The absence of lipophilic side chains on the benzoate unit was important for the biological activity. Thus, non-mesomorphic tyrosine benzoates and crown ether benzoates devoid of additional side chains at the benzoate unit displayed the highest cytotoxicities (against L929 mouse fibroblast cell line) and antimicrobial activity (against Escherichia coli DTolC and Staphylococcus aureus) and promising selectivity ratio in favour of antimicrobial activity. KW - Liquid Crystals PY - 2023 U6 - https://doi.org/10.1039/d3cp00485f SN - 1463-9076 VL - 25 IS - 26 SP - 17639 EP - 17656 PB - RCS AN - OPUS4-57796 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kang, Y. A1 - Nack, L. M. A1 - Liu, Y. A1 - Qi, B. A1 - Huang, Y. A1 - Liu, Z. A1 - Chakraborty, I. A1 - Schulz, F. A1 - Ahmed, A. A. A. A1 - Poveda, M. C. A1 - Hafizi, F. A1 - Roy, S. A1 - Mutas, M. A1 - Holzapfel, M. A1 - Sanchez-Cano, C. A1 - Wegner, Karl David A1 - Feliu, N. A1 - Parak, W. J. T1 - Quantitative considerations about the size dependence of cellular entry and excretion of colloidal nanoparticles for different cell types N2 - Most studies about the interaction of nanoparticles (NPs) with cells have focused on how the physicochemical properties of NPs will influence their uptake by cells. However, much less is known about their potential excretion from cells. However, to control and manipulate the number of NPs in a cell, both cellular uptake and excretion must be studied quantitatively. Monitoring the intracellular and extracellular amount of NPs over time (after residual noninternalized NPs have been removed) enables one to disentangle the influences of cell proliferation and exocytosis, the major pathways for the reduction of NPs per cell. Proliferation depends on the type of cells, while exocytosis depends in addition on properties of the NPs, such as their size. Examples are given herein on the role of these two different processes for different cells and NPs. KW - Cell proliferation KW - Exocytosis KW - Gold nanoparticles KW - Quantum dots KW - Fluorescence KW - Uptake studies PY - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-543476 SN - 2199-3793 VL - 8 IS - 1 SP - 1 EP - 8 PB - Springer CY - Berlin AN - OPUS4-54347 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Kang, Y. A1 - Nack, L. A1 - Liu, Y. A1 - Qi, B. A1 - Huang, Y. A1 - Liu, Z. A1 - Chakraborty, I. A1 - Schulz, F. A1 - Ahmed, A. A. A1 - Poveda, M. C. A1 - Hafizi, F. A1 - Roy, S. A1 - Mutas, M. A1 - Holzapfel, M. A1 - Sanchez-Cano, C. A1 - Wegner, Karl David A1 - Feliu, N. A1 - Parak, W. J. T1 - Correction to: Quantitative considerations about the size dependency for cellular entry and excretion of colloidal nanoparticles for different cell types N2 - We regret to inform that the labels "NPs which remain in endosomes/lysosomes" and "exocytosed NPs" had been erroneously swapped in the sketch on the right side in Figure 2. The corrected Fig. 2 is displayed below. WJP apologizes for this error. KW - Cell proliferation KW - Exocytosis KW - Gold nanoparticles KW - Quantum dots KW - Uptake studies PY - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-554519 VL - 8 IS - 17 SP - 1 EP - 2 PB - Springer CY - Berlin AN - OPUS4-55451 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Knelles, J. A1 - Wanner, C. A1 - Schulz, F. A1 - Freund, M. A1 - Kolmangadi, Mohamed Aejaz A1 - Baro, A. A1 - Huber, P. A1 - Schönhals, Andreas A1 - Lachat, S. T1 - Liquid crystalline hydrazones revisited: dipolar interactions vs hydrogen bonding affecting mesomorphic properties N2 - In order to understand the role of dipolar interactions vs. H-bonding, a series of hydrazones were synthesised from 4-alkoxy-, 3,4-dialkoxy- or 3,4,5-trialkoxybenzaldehydes and phenyl, bromo- or nitrophenylhydrazine, respectively. Their mesomorphic properties were investigated by differential scanning calorimetry (DSC), polarising optical microscopy (POM), X-ray diffraction (WAXS, SAXS) and compared with known members. Only those hydrazones derived from 3,4,5-trisalkoxybenzaldehyde and either meta, meta-dinitro- or ortho, para-dinitrophenylhydrazine displayed hexagonal columnar mesophases. All other derivatives were non-mesomorphic, even when H-bonds were present. Dipole moments of the various nitro-substituted hydrazones were experimentally determined by dielectric measurements and supported by theoretical DFT calculations, which indicated that the mesophase formation is mostly governed by strong dipole moment and further enforced by intramolecular H-bonding. KW - Discotic liquid crystals PY - 2021 U6 - https://doi.org/10.1080/02678292.2021.1873438 VL - 48 IS - 10 SP - 1382 EP - 1391 PB - Taylor & Francis AN - OPUS4-52409 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -