An initiator- and catalyst-free hydrogel coating process for 3D printed medical-grade poly(ε-caprolactone)

• Jochen Löblein,
• Thomas Lorson,
• Miriam Komma,
• Tobias Kielholz,
• Maike Windbergs,
• Paul D. Dalton and
• Robert Luxenhofer

Beilstein J. Org. Chem. 2021, 17, 2095–2101, doi:10.3762/bjoc.17.136

• ), however, this morphology is highly irregular. A change in wetting behavior could be demonstrated, and toluidine blue staining indicates successful SIPGP of HEMA on PCL scaffolds. However, to prove that this material is indeed PHEMA, we performed confocal Raman microscopy on the samples, which allows a

• , the high PCL signal intensity covers most of the signals originating from the thin PHEMA coating directly deposited on fibers (Supporting Information File 1, Figure S4; a 3D Raman reconstruction is provided in Supporting Information File 2). Scanning electron microscopy (SEM) corroborates this fiber

Chemical approaches to discover the full potential of peptide nucleic acids in biomedical applications

• Nikita Brodyagin,
• Martins Katkevics,
• Venubabu Kotikam,
• Christopher A. Ryan and
• Eriks Rozners

Beilstein J. Org. Chem. 2021, 17, 1641–1688, doi:10.3762/bjoc.17.116

• triplex, most likely due to reduced ability of R to π-stack [103]. As expected, fluorescence microscopy showed improved cellular uptake of the cationic guanidinium-modified PNAs [103]. PNA nucleobases for Hoogsteen recognition of adenine: Because the T•A–T triplets are reasonably stable under

Synthesis of 1-indolyl-3,5,8-substituted γ-carbolines: one-pot solvent-free protocol and biological evaluation

• Premansh Dudhe,
• Mena Asha Krishnan,
• Kratika Yadav,
• Diptendu Roy,
• Krishnan Venkatasubbaiah,
• Biswarup Pathak and
• Venkatesh Chelvam

Beilstein J. Org. Chem. 2021, 17, 1453–1463, doi:10.3762/bjoc.17.101

• experiments were performed. In brief, HeLa cells were incubated with carboline 3ac (10 μM and 100 nM), and the cellular uptake was examined using confocal microscopy (λex = 405 nm; λem = 420–470 nm). Compound 3ac showed excellent cytosolic uptake in cancer cells when incubated at a 10 μM concentration (Figure

• derivative 3ac (10 nM, 100 nM, 1 μM, 10 μM, and 100 μM), the cellular uptake and distribution was monitored by using confocal microscopy (λex = 405 nm; λem range = 420–470 nm). Selected examples of compounds containing the γ-carboline core. Single-crystal XRD structure of 3ac (CCDC: 1897787). UV–vis

• , 3ca, 3ga in the breast cancer cell line, MCF7 and (B) doxorubicin against the panel of tested cancer cell lines. Dose–response curve of γ-carbolines 3ac, 3bc, 3ca, 3ga in macrophage cell line, RAW264.7. Laser scanning confocal microscopy studies (λex = 405 nm; collection range = 420–470 nm) for uptake

Antiviral therapy in shrimp through plant virus VLP containing VP28 dsRNA against WSSV

• Santiago Ramos-Carreño,
• Ivone Giffard-Mena,
• Jose N. Zamudio-Ocadiz,
• Alfredo Nuñez-Rivera,
• Ricardo Valencia-Yañez,
• Jaime Ruiz-Garcia,
• Maria Teresa Viana and
• Ruben D. Cadena-Nava

Beilstein J. Org. Chem. 2021, 17, 1360–1373, doi:10.3762/bjoc.17.95

• in a horizontal agarose gel system (FBSB710 Fisher Scientific) for 4 h at 50 volts (virus buffer), 4 °C and then, the gel was stained with ethidium bromide. The image was captured using a documentation system (MS Major Science). Transmission electron microscopy analysis of VLPs. 6 µL of VLP-dsRNAvp28

• to the wild type CCMV (lane 2 and 3, respectively, in Figure 1). In contrast, the free dsRNAvp28 ran faster (lane 4 in Figure 1) in comparison with the sample and wild type CCMV, as an indication of VLPs formation. The VLPs assembly at each stage was analyzed by transmission electron microscopy (TEM

Icilio Guareschi and his amazing “1897 reaction”

• Gian Cesare Tron,
• Alberto Minassi,
• Giovanni Sorba,
• Mara Fausone and
• Giovanni Appendino

Beilstein J. Org. Chem. 2021, 17, 1335–1351, doi:10.3762/bjoc.17.93

• differential scanning microscopy studies [64]. In connection with the work on the restauration of parchments, Guareschi developed an interest in the chemistry and technology of ancient inks and dyes, a topic he covered in some monumental monographs [65]. These, and the study on the history of chemistry, filled

Photoinduced post-modification of graphitic carbon nitride-embedded hydrogels: synthesis of 'hydrophobic hydrogels' and pore substructuring

• Cansu Esen and
• Baris Kumru

Beilstein J. Org. Chem. 2021, 17, 1323–1334, doi:10.3762/bjoc.17.92

• analysis to evaluate the vTA incorporation, and microscopy techniques were employed to examine the impact on their morphology. In terms of applicability, water contact angle measurement, equilibrium swelling ratio analysis, and dye releasing efficiency experiment were also conducted. All hydrogel samples

• , Figure S1). Scanning electron microscopy was performed to investigate the morphology of freeze-dried HGCM and HGCM-vTA. As shown in Figure 2a, HGCM exhibits a significantly porous and uniform morphology. Formation of accessible pores for vTA was the key point to reach in order to activate g-CN nanosheets

• performed via inductively coupled plasma optical emission spectroscopy (ICP-OES Optima 8000). Scanning electron microscopy (SEM) and EDX elemental mapping were performed using a JSM-7500F (JEOL) microscope equipped with an Oxford Instruments X-Max 80 mm2 detector for the determination of both elemental

A new glance at the chemosphere of macroalgal–bacterial interactions: In situ profiling of metabolites in symbiosis by mass spectrometry

• Marine Vallet,
• Filip Kaftan,
• Veit Grabe,
• Fatemeh Ghaderiardakani,
• Simona Fenizia,
• Aleš Svatoš,
• Georg Pohnert and
• Thomas Wichard

Beilstein J. Org. Chem. 2021, 17, 1313–1322, doi:10.3762/bjoc.17.91

• -pyrimidinecarboxylic acid) was found in bacterial presence. Ectoine was used as a metabolic marker for localisation studies of Roseovarius sp. within the tripartite community because it was produced exclusively by these bacteria. By combining confocal laser scanning microscopy (cLSM) and AP-SMALDI-HRMS, we proved that

• reveal any information on the metabolically active bacteria and the spatial distribution of substances exchanged. While the study of bacterial symbiosis is often limited to either chemistry or microscopy work, recent functional and metabolomics methods are available to enable chemical imaging of

• profile fingerprint matching [26][27][28]. Our research combines cutting-edge laser scanning microscopy and high-resolution mass spectrometry to uncover Ulva/bacteria interactions and specialised metabolites at the microscale level. In this study, we demonstrate that the chemosphere of U. mutabilis

Enhanced target cell specificity and uptake of lipid nanoparticles using RNA aptamers and peptides

• Roslyn M. Ray,
• Anders Højgaard Hansen,
• Maria Taskova,
• Bernhard Jandl,
• Jonas Hansen,
• Citra Soemardy,
• Kevin V. Morris and
• Kira Astakhova

Beilstein J. Org. Chem. 2021, 17, 891–907, doi:10.3762/bjoc.17.75

• assessed by nanoparticle tracking analysis (NTA, Table 3) and transmission electron microscopy (TEM, Supporting Information File 1, Figure S2). After postinsertion, LNP sizes were found by NTA to range from 54–66 nm (Table 3), while TEM analysis revealed average sizes between 45–52 nm (Supporting

• a tight junction barrier has formed within these cells and can be used to determine the ability of the LNPs to pass through the BBB (Supporting Information File 1, Figure S3A). Additionally, we further confirmed our junctions using fluorescent microscopy on the barrier layers to confirm expression

• (phosphate-buffered saline, PBS) conditions (Figure 4A). Additionally, we confirmed LNP uptake by the monocyte-derived macrophages (MDMs) using fluorescent microscopy (Figure 4B). We found that all LNPs containing the Cy5 oligonucleotide were observable under the microscope (Figure 4B) and that all

DNA with zwitterionic and negatively charged phosphate modifications: Formation of DNA triplexes, duplexes and cell uptake studies

• Yongdong Su,
• Maitsetseg Bayarjargal,
• Tracy K. Hale and
• Vyacheslav V. Filichev

Beilstein J. Org. Chem. 2021, 17, 749–761, doi:10.3762/bjoc.17.65

• microscopy. Figure 3 shows that FAM-labelled Ts and N+-modified DNAs are concentrated in vesicles (punctate foci in the oligo/FAM panel) that accumulate around the edge of the nucleus. Interestingly, the Ts-modified oligo is also present in the nucleus as indicated by the colocalisation of the ON (Figure 3E

• are shown for each section, along with merge where pseudo-coloured panels are overlaid, nucleus (blue) and oligo (magenta). Scale bar: 40 μm. Representative confocal microscopy section showing the FAM vesicles inside the cell. Mouse NIH 3T3 fibroblasts were incubated with 20 µM of the FAM-labelled 4Ts

• Information Supporting Information File 62: Experimental part. Acknowledgements Manawatu Microscopy and Imaging Centre, NMR and mass spectrometry facilities at Massey University, and the assistance of Mr. Raoul Solomon, Dr. Patrick J. B. Edwards, and Mr. David Lun are gratefully acknowledged. We thank Dr

A new and efficient methodology for olefin epoxidation catalyzed by supported cobalt nanoparticles

• Lucía Rossi-Fernández,
• Viviana Dorn and
• Gabriel Radivoy

Beilstein J. Org. Chem. 2021, 17, 519–526, doi:10.3762/bjoc.17.46

• confirming the heterogeneous nature of the catalytic method. The freshly prepared CoNPs/MgO catalyst was characterized by means of transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDX), inductively coupled plasma atomic emission spectroscopy (ICP-AES), X-ray diffraction (XRD) and

• determined with a Shimadzu GC-14B instrument equipped with a flame-ionisation detector and a 30 m column (HP-5MS, 0.25 mm, 0.25 μm), using nitrogen as carrier gas. Catalyst characterization The freshly prepared catalyst was characterized by transmission electron microscopy (TEM) in a JEOL 100CX2 instrument

Synthesis and physicochemical evaluation of fluorinated lipopeptide precursors of ligands for microbubble targeting

• Masayori Hagimori,
• Estefanía E. Mendoza-Ortega and
• Marie Pierre Krafft

Beilstein J. Org. Chem. 2021, 17, 511–518, doi:10.3762/bjoc.17.45

• increase MB half-lives. The microbubbles were prepared by mechanical agitation using a Vialmix shaker and were characterized by optical microscopy immediately after the preparation and over time. The results show that the incorporation of F-lipopeptides 1–3 led to MBs that are somewhat smaller than those

¹⁹F NMR as a tool in chemical biology

• Diana Gimenez,
• Aoife Phelan,
• Cormac D. Murphy and
• Steven L. Cobb

Beilstein J. Org. Chem. 2021, 17, 293–318, doi:10.3762/bjoc.17.28

• their functional architecture. Such an approach typically includes the use of a variety of high-resolution proteomic tools, cryo-electron microscopy and X-ray crystallography to achieve full molecular characterization at the atomic level. However, macromolecules such as DNA/RNA and proteins are not

• ionization and ion mobility), CD spectroscopy and atomic force microscopy, the authors were able to obtain detailed information about the size and secondary structure associated with some of the soluble intermediates. These included: large β-sheet oligomers formed immediately after solubilization (oligomer

Multiswitchable photoacid–hydroxyflavylium–polyelectrolyte nano-assemblies

• Alexander Zika and
• Franziska Gröhn

Beilstein J. Org. Chem. 2021, 17, 166–185, doi:10.3762/bjoc.17.17

• were used. Atomic force microscopy (AFM) was performed using a NanoWizard 4 from JPK instrument (Berlin, Germany) operated in the tapping-mode with a fixed-spring cantilever holder and a USC-F0.3-k0.3-10 ultrashort cantilever with a force constant of 0.3 Nm−1. The cantilever has been tested and

Tuning the solid-state emission of liquid crystalline nitro-cyanostilbene by halogen bonding

• Subrata Nath,
• Alexander Kappelt,
• Matthias Spengler,
• Bibhisan Roy,
• Jens Voskuhl and
• Michael Giese

Beilstein J. Org. Chem. 2021, 17, 124–131, doi:10.3762/bjoc.17.13

• subsequent drying in vacuo yielded the desired assemblies. The mesomorphic behaviour of the assemblies was investigated by polarised optical microscopy (POM) and differential scanning calorimetry (DSC). It should be noted that the individual building blocks F4St and F4Az as well as NO2-C8 and NO2-C9 do not

Supramolecular polymerization of sulfated dendritic peptide amphiphiles into multivalent L-selectin binders

• David Straßburger,
• Svenja Herziger,
• Katharina Huth,
• Moritz Urschbach,
• Rainer Haag and
• Pol Besenius

Beilstein J. Org. Chem. 2021, 17, 97–104, doi:10.3762/bjoc.17.10

• Research Center of Electron Microscopy, Freie Universität Berlin, Fabeckstr. 34a, 14195 Berlin 10.3762/bjoc.17.10 Abstract The synthesis of a sulfate-modified dendritic peptide amphiphile and its self-assembly into one-dimensional rod-like architectures in aqueous medium is reported. The influence of the

• ionic strength on the supramolecular polymerization was probed via circular dichroism spectroscopy and cryogenic transmission electron microscopy. Physiological salt concentrations efficiently screen the charges of the dendritic building block equipped with eight sulfate groups and trigger the formation

• the effect of sulfate modification on the self-assembly properties of the dendritic peptide amphiphiles were performed using circular dichroism (CD) spectroscopy and electron transmission microscopy (TEM) as well as cryogenic TEM. Finally, the binding affinity of the sulfated supramolecular polymers

Control over size, shape, and photonics of self-assembled organic nanocrystals

• Chen Shahar,
• Yaron Tidhar,
• Yunmin Jung,
• Haim Weissman,
• Sidney R. Cohen,
• Ronit Bitton,
• Iddo Pinkas,
• Gilad Haran and
• Boris Rybtchinski

Beilstein J. Org. Chem. 2021, 17, 42–51, doi:10.3762/bjoc.17.5

• medium. The ONCs have a thin rectangular shape, with an aspect ratio that is controlled by the content of the organic cosolvent (THF). The nanocrystals were characterized in solution by cryogenic transmission electron microscopy (cryo-TEM) and small-angle X-ray scattering. The ONCs retain their structure

• upon drying, as was evidenced by TEM and atom force microscopy. Photophysical studies, including femtosecond transient absorption spectroscopy, revealed a distinct influence of the ONC morphology on their photonic properties (excitation energy transfer was observed only in the high-aspect ONCs

• inversion, red shift, and significant broadening in comparison to the molecularly dissolved system (Figure 1B). This is a typical spectral signature of ordered PDI systems and crystals [38][43][44][45][46][47] having a face-to-face orientation of the π-systems. Cryogenic transmission electron microscopy

Molecular basis for protein–protein interactions

• Brandon Charles Seychell and
• Tobias Beck

Beilstein J. Org. Chem. 2021, 17, 1–10, doi:10.3762/bjoc.17.1

• microscopy (cryo-EM) [14]. Traditionally, X-ray crystallography was the preferred method to solve the protein structure and determine protein–protein interfaces. However, protein crystallography has the limitation that some protein assemblies have a low diffraction quality and are difficult to crystallise

• [15]. In the past few years, advances in the cryo-EM technology attracted the interest of more and more structural biologists. In fact, the number of cryo-EM structures has steadily been increasing over the recent years, with over 12,500 electron density maps being deposited in the Electron Microscopy

Selected peptide-based fluorescent probes for biological applications

• Debabrata Maity

Beilstein J. Org. Chem. 2020, 16, 2971–2982, doi:10.3762/bjoc.16.247

• . Thus, it acts as inhibitor by preventing the substrate to reach the active sites in β-tryptase. Confocal laser scanning microscopy (CLSM) confirms that peptide 9 is mast-cell permeable and exhibits inhibitory activity within cells by suppressing their growth (Figure 8B). Heparin detection Heparin is a

• laser scanning microscopy images of CHMAS cells treated with 10 μM peptide 9 for 30 min. Reproduced from [51], “A fluorescent light-up probe as an inhibitor of intracellular β-tryptase”, © 2014 Wang et al., licensed under a Creative Commons Attribution 3.0 Unported Licence, https://creativecommons.org

Ultrasound-assisted Strecker synthesis of novel 2-(hetero)aryl-2-(arylamino)acetonitrile derivatives

• Emese Gal,
• Luiza Gaina,
• Hermina Petkes,
• Alexandra Pop,
• Castelia Cristea,
• Gabriel Barta,
• Dan Cristian Vodnar and
• Luminiţa Silaghi-Dumitrescu

Beilstein J. Org. Chem. 2020, 16, 2929–2936, doi:10.3762/bjoc.16.242

• precipitated from the reaction mixture in crystalline form as depicted by scanning electron microscopy (SEM) analysis. The single crystal X-ray diffraction analysis disclosed the arrangement of the α-(arylamino)acetonitrile molecules in the aggregated crystalline state as a racemic mixture. The mutagenic

• angle of 64.5°. The intermolecular distances are situated in the range 2.3–2.6 Å disclosing the lack of intermolecular interactions in the crystal structure. Scanning electron microscopy (SEM) analysis Besides process intensification leading to a shorter reaction time, another advantage of the

A novel and robust heterogeneous Cu catalyst using modified lignosulfonate as support for the synthesis of nitrogen-containing heterocycles

• Bingbing Lai,
• Meng Ye,
• Ping Liu,
• Minghao Li,
• Rongxian Bai and
• Yanlong Gu

Beilstein J. Org. Chem. 2020, 16, 2888–2902, doi:10.3762/bjoc.16.238

• results indicated that all prepared materials could remain stable in the system when used to catalyze organic reactions. FSEM (field emission scanning electron microscopy) and FTEM (field emission transmission electron microscopy) were used to observe the surface morphologies of different catalysts, and

• ) conditions. ICP-MS data were recorded on ELAN DRC-e device. The morphologies of samples were observed by scanning electron microscopy (SEM, Sirion 200, Holland) equipped with an energy dispersive X-ray (EDX) spectroscopy and transmission electron microscopy (TEM, Talos F200X), respectively. 1H and 13C NMR

Dirhamnolipid ester – formation of reverse wormlike micelles in a binary (primerless) system

• David Liese,
• Hans Henning Wenk,
• Xin Lu,
• Jochen Kleinen and
• Gebhard Haberhauer

Beilstein J. Org. Chem. 2020, 16, 2820–2830, doi:10.3762/bjoc.16.232

• is typical for wormlike micelle systems, the normalized Cole–Cole plot of G''/G''max against G'/G''max was obtained as a semicircle centered at G'/G''max = 1. The formation of network structures was also verified by polarized light microscopy. The sample was birefringent at ambient temperature and

• supported by rheological measurements [42] and finally validated by transmission electron microscopy at cryogenic temperature (cryo-TEM) [43]. Temperature-dependent rheology Next, the temperature dependence of the rheology for the RWLM will be described. Oscillatory-shear experiments were performed for the

• due to the intramicellar branches and/or the inverse character of the micelles, as Equation 9 and Equation 10 are defined for normal linear micelles. The behavior of G0 varying with the temperature for inverse micelles was also found by other authors [53][54]. Microscopy Polarized optical microscopy

Selective recognition of ATP by multivalent nano-assemblies of bisimidazolium amphiphiles through “turn-on” fluorescence response

• Rakesh Biswas,
• Surya Ghosh,
• Shubhra Kanti Bhaumik and
• Supratim Banerjee

Beilstein J. Org. Chem. 2020, 16, 2728–2738, doi:10.3762/bjoc.16.223

• derivatives in aqueous buffer (5 mM tris-HCl, 10 mM NaCl, water/DMSO 99.5:0.5, pH 7.4) were investigated using a combination of absorption and emission spectral studies, dynamic light scattering (DLS) and field emission scanning electron microscopy (FESEM). In a “good solvent” such as DMSO, in which all

Enzyme-instructed morphological transition of the supramolecular assemblies of branched peptides

• Dongsik Yang,
• Hongjian He and
• Bing Xu

Beilstein J. Org. Chem. 2020, 16, 2709–2718, doi:10.3762/bjoc.16.221

• nanofibers in the HeLa cells. Then, we used confocal laser scanning microscopy (CLSM) to examine whether these compounds deliver RPE into HeLa cells. After mixing R-phycoerythrin (RPE) [49], a red fluorescent protein, with 1 or 2 at different concentrations, we incubated the mixtures with HeLa cells for 2 h

Optical detection of di- and triphosphate anions with mixed monolayer-protected gold nanoparticles containing zinc(II)–dipicolylamine complexes

• Lena Reinke,
• Julia Bartl,
• Marcus Koch and
• Stefan Kubik

Beilstein J. Org. Chem. 2020, 16, 2687–2700, doi:10.3762/bjoc.16.219

• )–dipicolylamine complexes beyond 25% had a negative impact on the limit of detection and the optical response. Transmission electron microscopy provided evidence that the changes of the nanoparticle properties observed in the presence of the phosphates were due to a nanoparticle crosslinking, consistent with the

• signals of the immobilized ligand molecules but no sharp signals, showing that the nanoparticles were not contaminated with unbound ligands or residual citrate. According to transmission electron microscopy (TEM), NPrac-1 had an average diameter of 9.1 ± 2.4 nm and a maximum of the SPR band in the UV–vis

Particle size effect in the mechanically assisted synthesis of β-cyclodextrin mesitylene sulfonate

• Stéphane Menuel,
• Sébastien Saitzek,
• Eric Monflier and
• Frédéric Hapiot

Beilstein J. Org. Chem. 2020, 16, 2598–2606, doi:10.3762/bjoc.16.211

• highlighting the advantages of the mechanically assisted synthesis. Results and Discussion Analysis of ground CDs Scanning electron microscopy (SEM) SEM enables particle size evolution upon grinding to be monitored. The SEM images in Figure 1 show the surface topography changes of polycrystalline β-CD for six

• speed of 0.4°/min) using the Bragg–Brentano configuration. Scanning electron microscopy Scanning electron microscopy (SEM) images were recorded on a SEM JEOL JSM-7800F LV instrument at 3.0 kV. The powder was deposited on a carbon-coated copper grid. The particle size distributions were determined from