Interactions between shape-persistent macromolecules as probed by AFM

• Johanna Blass,
• Jessica Brunke,
• Franziska Emmerich,
• Cédric Przybylski,
• Vasil M. Garamus,
• Artem Feoktystov,
• Roland Bennewitz,
• Gerhard Wenz and
• Marcel Albrecht

Beilstein J. Org. Chem. 2017, 13, 938–951, doi:10.3762/bjoc.13.95

• spectroscopy, quartz crystal microbalance (QCM), surface plasmon resonance (SPR) and atomic force microscopy (AFM) have been employed to quantify the strength of the multivalent interactions [8]. Because binding affinities can be very high for multivalent supramolecular systems, the constituents are commonly

• attachment. The distribution of the maximum rupture lengths in the force microscopy experiments confirms the molecular weight distribution of the CD polymers estimated by MALDI–TOF and the average contour length determined by SANS/SAXS. In addition, force microscopy experiments emphasize the longest polymer

Expression, purification and structural analysis of functional GABA transporter 1 using the baculovirus expression system

• Jing Hu,
• Chris Weise,
• Christoph Böttcher,
• Hua Fan and
• Jian Yin

Beilstein J. Org. Chem. 2017, 13, 874–882, doi:10.3762/bjoc.13.88

• and size-exclusion fast protein liquid chromatography (SE-FPLC). A yield of 200–300 μg of the GAT1/GFP protein could be purified from 400–600 mL of infected Sf9 cells. The purified protein was analyzed by transmission electron microscopy (TEM), which revealed that the GAT1/GFP fusion protein was

• microscopy (Figure 1B). The expression of GAT1/GFP in insect cells was further determined by sodium dodecyl sulfate polyacrylamide gel electrophoresis SDS-PAGE, followed by Western blotting with either anti-GFP pAb (Figure 1C) or anti-GAT1 pAb (Figure 1D) and silver staining (Figure 1E) after

• molecular weight of approximately 70 kDa, and the overlapping peak 2 (14.7 mL) corresponds to a molecular weight of 45 kDa, which was determined by comparison with the protein standards (Figure 4B). Transmission electron microscopy (TEM) analysis Cryogenic TEM (cryo-TEM) was employed to analyze both peaks

Continuous-flow processes for the catalytic partial hydrogenation reaction of alkynes

• Carmen Moreno-Marrodan,
• Francesca Liguori and
• Pierluigi Barbaro

Beilstein J. Org. Chem. 2017, 13, 734–754, doi:10.3762/bjoc.13.73

• structural components distinguishable by optical microscopy” [102]. According to this definition, honeycombs do not fall within this category. In the recent years, porous monoliths have attracted considerable interest in several flow-through applications for the fine chemistry, including chromatography and

Membrane properties of hydroxycholesterols related to the brain cholesterol metabolism

• Malte Hilsch,
• Ivan Haralampiev,
• Peter Müller,
• Daniel Huster and
• Holger A. Scheidt

Beilstein J. Org. Chem. 2017, 13, 720–727, doi:10.3762/bjoc.13.71

• of several hydroxycholesterols with those of cholesterol using 2H NMR spectroscopy, a membrane permeability assay, and fluorescence microscopy experiments. It is shown that hydroxycholesterols do not exert the unique impact on membrane properties characteristic for cholesterol with regard to the

• properties such as lipid chain packing, membrane permeability, and membrane domain formation is investigated. These parameters are compared with those obtained for cholesterol by using various biophysical techniques such as NMR and fluorescence spectroscopy as well as fluorescence microscopy. Results Lipid

• of the vesicles. The fluorescence microscopy images of cholesterol-containing GUVs show large membrane regions of low and of high fluorescence intensity, representing the lo and ld phase, respectively (Figure 4A). Note, that the vesicle shown in Figure 4A probably forms another dark lo domain on the

Fluorescent carbon dots from mono- and polysaccharides: synthesis, properties and applications

• Stephen Hill and
• M. Carmen Galan

Beilstein J. Org. Chem. 2017, 13, 675–693, doi:10.3762/bjoc.13.67

• internalisation studies with HepG2 cells [29]. The green CDs were non-toxic to cells at concentrations of up to 625 μg/mL and exposures of 72 h. Laser scanning confocal microscopy (LSCM) demonstrated cell internalization, making these materials a good candidate as a bioimaging agent. In 2011 Qu et al. developed a

• labelled with either TAT (a cell-penetrating peptide), or folate and then incubated with HeLa cells. Fluorescence microscopy images confirmed that incubation times of 3–6 hours were adequate to allow for CD labelling of the cells. Further toxicity assays indicated that concentrations of up to 200 μg/mL

• the CDs, while significant toxicity was seen at concentrations at and above 400 μg/mL. CDs (100 μg/mL) were also incubated with HepG2 for 24 h and laser scanner confocal microscopy (LCSM) was used to image the internalization of the CDs within the cells using the green, yellow and red channels

Isoxazole derivatives as new nitric oxide elicitors in plants

• Anca Oancea,
• Emilian Georgescu,
• Florentina Georgescu,
• Alina Nicolescu,
• Elena Iulia Oprita,
• Catalina Tudora,
• Lucian Vladulescu,
• Marius-Constantin Vladulescu,
• Florin Oancea and
• Calin Deleanu

Beilstein J. Org. Chem. 2017, 13, 659–664, doi:10.3762/bjoc.13.65

• of both NO and ROS was proven by fluorescence microscopy using specific fluorescence indicators that help to exactly define the sites of generation. We used Arabidopsis thaliana wild type seeds, cultivated for six weeks in laboratory in Arasystem [60]. Arabidopsis thaliana was selected as model

• 50 μg/mL, respectively) and collected after 24 h. Collected leaves were washed with distilled water and incubated with the specific fluorescence indicator for histochemical analysis of ROS and NO by fluorescence microscopy. Arabidopsis leaves untreated with inductor suspensions have been used as

• diacetate), a non-fluorescent compound, which reacts with NO to form a fluorescent benzotriazole and does not react with any ROS [64][65][66][67]. Fluorescence microscopy images of all 3,5-disubstituted isoxazoles-treated Arabidopsis leaves showed a pronounced presence of ROS at both concentrations of

Fast and efficient synthesis of microporous polymer nanomembranes via light-induced click reaction

• Qi An,
• Youssef Hassan,
• Xiaotong Yan,
• Peter Krolla-Sidenstein,
• Tawheed Mohammed,
• Mathias Lang,
• Stefan Bräse and
• Manuel Tsotsalas

Beilstein J. Org. Chem. 2017, 13, 558–563, doi:10.3762/bjoc.13.54

• selectively dissolved using cyclohexane. Afterwards we dissolved the sacrificial substrate to obtain the freestanding CMP membranes. To investigate the freestanding CMP nanomembrane we transferred it to a copper grid and recorded scanning electron microscopy (SEM) images. Figure 4 shows the SEM images of the

• electron microscopy (SEM): We recorded SEM images using a FEI Philips XL30 (FEI Co., Eindhoven, NL), a field emission gun environmental scanning electron microscope (FEG-ESEM). Samples have been coated with a thin layer (about 5 nm) of a gold/palladium film in order to avoid charging and improve samples

• conductivity. All specimen were imaged under high-vacuum conditions (1.0 Torr), using an acceleration voltage of 20 keV. Atomic force microscopy (AFM): AFM-imaging was performed using an Asylum Research Atomic Force Microscope, MFP-3D BIO. The AFM was operated at 25 °C in an isolated chamber in alternating

A new class of organogelators based on triphenylmethyl derivatives of primary alcohols: hydrophobic interactions alone can mediate gelation

• Wangkhem P. Singh and
• Rajkumar S. Singh

Beilstein J. Org. Chem. 2017, 13, 138–149, doi:10.3762/bjoc.13.17

• the gel were carried out using scanning electron microscopy, FTIR spectroscopy, rheology and powder XRD techniques. This gel also showed a good absorption profile for a water soluble dye. Given the non-polar nature of this molecule, gel formation is likely to be mediated by hydrophobic interactions

• microscopic structures and morphologies of the gels formed by the gelators, scanning electron microscopy (SEM) studies were performed with the dried gels [33]. Dried gels (xerogels) were obtained from the gels by evaporation of the solvent. The morphologies for TPM-G12 and TPM-G5 are drastically different

• with minimum gelation concentration in the range of 0.5–4.0%, w/v. 1,8-Bis(trityloxy)octane, the ditrityl derivative of 1,8-octanediol was found to be an excellent gelator of some polar solvents. Detailed characterizations of the gel were carried out using scanning electron microscopy, FTIR

A postsynthetically 2’-“clickable” uridine with arabino configuration and its application for fluorescent labeling and imaging of DNA

• Heidi-Kristin Walter,
• Bettina Olshausen,
• Ute Schepers and
• Hans-Achim Wagenknecht

Beilstein J. Org. Chem. 2017, 13, 127–137, doi:10.3762/bjoc.13.16

• transfected with 15 pmol of the above mentioned DNA duplexes and Screenfect®, for 24 hours at a concentration, which was not toxic for the cells (see cytotoxicity test in Supporting Information File 1), and imaged by confocal fluorescent microscopy using the excitation wavelength of the energy donor (D1, λexc

• to the cells. The cells were incubated for 24 h with the respective transfection mixture at 37 °C in a 5% CO2 atmosphere. The visualization of the DNA duplexes was performed by confocal laser scanning microscopy using a Leica TCS SPE (DMi8) inverted microscope with an ACS APO 63×/1.30 oil objective

• handheld UV lamp. Confocal microscopy of HeLa cells after transfection with DNA2aD1–DNA3rD5 (row 1), DNA2rD1–DNA3aD8 (row 2), DNA2aD2–DNA3aD8 (row 3) and DNA2rD4–DNA3aD8 (row 4). The visualization was performed using a Leica TCS-SPE (DMi8) inverted microscope with an ACS APO 63×/1.30 oil objective. For

Synthesis of multi-lactose-appended β-cyclodextrin and its cholesterol-lowering effects in Niemann–Pick type C disease-like HepG2 cells

• Keiichi Motoyama,
• Rena Nishiyama,
• Yuki Maeda,
• Taishi Higashi,
• Yoichi Ishitsuka,
• Yuki Kondo,
• Tetsumi Irie,
• Takumi Era and
• Hidetoshi Arima

Beilstein J. Org. Chem. 2017, 13, 10–18, doi:10.3762/bjoc.13.2

• of multi-Lac-β-CD (DSL5.6) The intracellular distribution of TRITC-multi-Lac-β-CD (DS5.6) in NPC-like HepG2 cells was assayed by confocal laser scanning microscopy, as reported previously [14]. Intracellular cholesterol levels post treatment with multi-Lac-β-CD (DSL5.6) The intracellular cholesterol

• . Cells were incubated in medium [FBS (−)] with or without 100 μM TRITC-CDs for 24 h. (B) The fluorescence intensities of TRITC-CDs were determined in ten randomly selected cells per image by confocal laser scanning microscopy and BZ-II analyzer. Data represents mean ± S.E.M. of three experiments. *p

Supramolecular frameworks based on [60]fullerene hexakisadducts

• Andreas Kraft,
• Johannes Stangl,
• Ana-Maria Krause,
• Klaus Müller-Buschbaum and
• Florian Beuerle

Beilstein J. Org. Chem. 2017, 13, 1–9, doi:10.3762/bjoc.13.1

• electron microscopy were carried out on activated and non-activated samples of HFF-3. They corroborate the strong anisotropic character of crystalline needles of the X-ray structure determination and do not show changes upon activation (see Figure S13 in Supporting in Information File 1). However, powder X

Versatile synthesis of end-reactive polyrotaxanes applicable to fabrication of supramolecular biomaterials

• Atsushi Tamura,
• Asato Tonegawa,
• Yoshinori Arisaka and
• Nobuhiko Yui

Beilstein J. Org. Chem. 2016, 12, 2883–2892, doi:10.3762/bjoc.12.287

• 7 could be utilized for monitoring the intracellular internalization of the PRXs, the intracellular uptake of 7 was investigated. HeLa cells were treated with 7 for 26 h, before observation by confocal laser scanning microscopy (CLSM) (Figure 5). The punctate 7 is clearly observed at the perinuclear

• installation of two fluorescent molecules at the terminals of the PRX is sufficient for detecting the intracellular trafficking and biodistribution of PRXs by fluorescence microscopy [38]. In addition, the terminal azide groups in the PRXs can act as installation moieties for magnetic resonance imaging (MRI

Computational methods in drug discovery

• Sumudu P. Leelananda and
• Steffen Lindert

Beilstein J. Org. Chem. 2016, 12, 2694–2718, doi:10.3762/bjoc.12.267

• , cryo-electron microscopy (cryoEM) has experienced a ‘resolution revolution’, leading to an increasing number of near-atomic resolution structures [18]. Experimental methods such as X-ray crystallography and NMR spectroscopy are associated with cost and time constraints, and are also limited by

Synthesis of three-dimensional porous hyper-crosslinked polymers via thiol–yne reaction

• Mathias Lang,
• Alexandra Schade and
• Stefan Bräse

Beilstein J. Org. Chem. 2016, 12, 2570–2576, doi:10.3762/bjoc.12.252

• crosslinking reaction conditions. The obtained HCPs showed BET surface areas up to 650 m²/g and are insoluble in common organic solvents. The characterisation of the networks was performed using IR spectroscopy, elemental analysis, thermogravimetric analysis (TGA), scanning electron microscopy (SEM), powder X

Effects of solvent additive on “s-shaped” curves in solution-processed small molecule solar cells

• John A. Love,
• Shu-Hua Chou,
• Ye Huang,
• Guilllermo C. Bazan and
• Thuc-Quyen Nguyen

Beilstein J. Org. Chem. 2016, 12, 2543–2555, doi:10.3762/bjoc.12.249

• -on” orientation adopted by p-SIDT(FBTTh2)2 [40], demonstrating how sensitive molecular self-assembly can be to relatively small molecular design choices. However, consistent with previous reports of related molecules, DIO does seem to improve crystallinity. Atomic force microscopy (AFM) topography

A self-assembled cyclodextrin nanocarrier for photoreactive squaraine

• Ulrike Kauscher and
• Bart Jan Ravoo

Beilstein J. Org. Chem. 2016, 12, 2535–2542, doi:10.3762/bjoc.12.248

• cyclodextrin vesicle surface. The supramolecular immobilization was monitored by using fluorescence spectroscopy and microscopy and the photochemistry of the squaraine was investigated by using absorption spectroscopy. Keywords: cyclodextrin; host–guest chemistry; photodynamic therapy; self-assembly

• amphiphilic cyclodextrins were formed by electroformation [35]. The obtained vesicles have a size of several micrometers and are thus directly visible by fluorescence microscopy. AdSq were added to a solution of the GUVs and immobilization of the molecules was examined with confocal fluorescence spectroscopy

• . The images taken show GUVs with a red luminescent membrane due to the squaraines bound to the GUV surface (Figure 4). Thus, fluorescence microscopy provided direct evidence for the immobilization of AdSq on the CDV. After the immobilization of AdSq on the surface of CDV was demonstrated, we

Inhibition of peptide aggregation by means of enzymatic phosphorylation

• Kristin Folmert,
• Malgorzata Broncel,
• Hans v. Berlepsch,
• Christopher H. Ullrich,
• Mary-Ann Siegert and
• Beate Koksch

Beilstein J. Org. Chem. 2016, 12, 2462–2470, doi:10.3762/bjoc.12.240

• and normalized to the starting value at t = 5 min of one. The shown plots represent an average of three independent measurements. Transmission electron microscopy Peptides, prepared as for CD spectroscopy measurements, were examined after 24 hours. Aliquots (6 µL) of the corresponding solution were

High performance p-type molecular electron donors for OPV applications via alkylthiophene catenation chromophore extension

• Paul B. Geraghty,
• Calvin Lee,
• Jegadesan Subbiah,
• Wallace W. H. Wong,
• James L. Banal,
• Mohammed A. Jameel,
• Trevor A. Smith and
• David J. Jones

Beilstein J. Org. Chem. 2016, 12, 2298–2314, doi:10.3762/bjoc.12.223

• optical microscopy (POM). POM was utilized in conjunction with a heating platform to directly observe these phase transitions and elucidate thin film structure. On heating at 10 °C·min−1 BQR shows a single phase transition to the isotropic melt at 202 °C, while on cooling we have identified an initial

Practical synthetic strategies towards lipophilic 6-iodotetrahydroquinolines and -dihydroquinolines

• David R. Chisholm,
• Garr-Layy Zhou,
• Ehmke Pohl,
• Roy Valentine and
• Andrew Whiting

Beilstein J. Org. Chem. 2016, 12, 1851–1862, doi:10.3762/bjoc.12.174

• range from the classic Skraup–Doebner–von Miller syntheses, to catalytic and asymmetric methods [2][3][4]. We required a straightforward synthesis of THQs and DHQs for the synthesis of a library of biocompatible fluorophores with the potential to be used in fluorescence microscopy applications. The

Effect of the π-conjugation length on the properties and photovoltaic performance of A–π–D–π–A type oligothiophenes with a 4,8-bis(thienyl)benzo[1,2-b:4,5-b′]dithiophene core

• Ni Yin,
• Lilei Wang,
• Yi Lin,
• Jinduo Yi,
• Lingpeng Yan,
• Junyan Dou,
• Hai-Bo Yang,
• Xin Zhao and
• Chang-Qi Ma

Beilstein J. Org. Chem. 2016, 12, 1788–1797, doi:10.3762/bjoc.12.169

• best performance for cells based on COOP-capped BDT derivatives [21][22][23][35][36][37]. Surface morphology of the blended films The surface morphology of the COOP-nHT-TBDT:PC61BM films was scrutinized with atomic force microscopy (AFM). Figure 4 depicts the topological images of the blended films

Synthesis and characterization of benzodithiophene and benzotriazole-based polymers for photovoltaic applications

• Desta Gedefaw,
• Marta Tessarolo,
• Margherita Bolognesi,
• Mario Prosa,
• Renee Kroon,
• Wenliu Zhuang,
• Patrik Henriksson,
• Kim Bini,
• Ergang Wang,
• Michele Muccini,
• Mirko Seri and
• Mats R. Andersson

Beilstein J. Org. Chem. 2016, 12, 1629–1637, doi:10.3762/bjoc.12.160

• force microscopy (AFM) images, recorded directly on tested devices, were taken with a Solver Pro (NT-934 MDT) scanning probe microscope in tapping mode. UV–visible absorption spectra of the pristine PTzBDT-1 and PTzBDT-2 (A) in chlorobenzene and chloroform, respectively and thin film processed from

Synthesis of a deuterated probe for the confocal Raman microscopy imaging of squalenoyl nanomedicines

• Eric Buchy,
• Branko Vukosavljevic,
• Maike Windbergs,
• Dunja Sobot,
• Camille Dejean,
• Simona Mura,
• Patrick Couvreur and
• Didier Desmaële

Beilstein J. Org. Chem. 2016, 12, 1127–1135, doi:10.3762/bjoc.12.109

• temperature 37 °C) for about 3–5 minutes. Evaporation was continued till the weight of the contents decreased to 0.8–0.9 g. Then, the volume of the suspension in the flask was made-up to 1.0 g using either 5% dextrose solution or milli-Q water. The colloidal dispersions were stored at 4 °C. Raman microscopy

• measurements. Confocal Raman microscopy measurements were performed with a WITec alpha 300R+ (WITec GmbH, Ulm, Germany). The excitation source was a diode laser with a wavelength of 532 nm adjusted to a power of 40 mW before the objective. A confocal pinhole of 50 μm rejected signals from out-of-focus regions

Separation and identification of indene–C₇₀ bisadduct isomers

• Bolong Zhang,
• Jegadesan Subbiah,
• David J. Jones and
• Wallace W. H. Wong

Beilstein J. Org. Chem. 2016, 12, 903–911, doi:10.3762/bjoc.12.88

• continuous interpenetrating networks. Some indications on the degree of phase separation can be obtained in tapping mode atomic force microscopy (AFM) experiments (see Supporting Information File 1 for experimental details). Both height and phase AFM images suggested unfavourable phase separation for blend

Syntheses of dibenzo[d,d']benzo[2,1-b:3,4-b']difuran derivatives and their application to organic field-effect transistors

• Minh Anh Truong and
• Koji Nakano

Beilstein J. Org. Chem. 2016, 12, 805–812, doi:10.3762/bjoc.12.79

• anti-DNBDF derivatives [39]. Analysis of thin films The vapor-deposited thin films of syn-DBBDF 5 and syn-DNBDF 6 were analyzed by X-ray diffraction (XRD) and atomic force microscopy (AFM). Figure 6 shows the out-of-plane XRD pattern and an AFM image of the thin film of syn-DNBDF 6 on the HMDS-treated

Creating molecular macrocycles for anion recognition

• Amar H. Flood

Beilstein J. Org. Chem. 2016, 12, 611–627, doi:10.3762/bjoc.12.60

• microscopy (STM) imaging. Their shape persistence makes them ideal for the study of structure–property relationships to enable deep understanding of anion recognition phenomena. The identification of 1,2,3-triazoles as linkers, ligands and building blocks. The synthetic creation of macrocycles sets the scene