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Search for "microscopy" in Full Text gives 309 result(s) in Beilstein Journal of Organic Chemistry. Showing first 200.
Anthelmintic drug discovery: target identification, screening methods and the role of open science
Beilstein J. Org. Chem. 2020, 16, 1203–1224, doi:10.3762/bjoc.16.105
- discovery by enabling finely detailed individual worm longitudinal microscopy. They have the potential to greatly reduce the amount of compound required for a screen hence enabling larger libraries to be economically screened. Encouragingly, some authors have made their microfluidic chip designs openly
Activated carbon as catalyst support: precursors, preparation, modification and characterization
Beilstein J. Org. Chem. 2020, 16, 1188–1202, doi:10.3762/bjoc.16.104
- properties with the preparation and modification methods. In the following, typical characterization techniques are introduced and the information obtained from the analytical methods is discussed on selected examples. Surface characterization Scanning electron microscopy (SEM): Surface morphology of
- constant. The activation process leads to an increase of oxygen, while all other elements decrease. Thus, the activation reagent (KOH) oxidizes the initial material during this step. As expected, the ammoxidation results in an enrichment of nitrogen [10]. Scanning electron microscopy with energy-dispersive
The charge-assisted hydrogen-bonded organic framework (CAHOF) self-assembled from the conjugated acid of tetrakis(4-aminophenyl)methane and 2,6-naphthalenedisulfonate as a new class of recyclable Brønsted acid catalysts
Beilstein J. Org. Chem. 2020, 16, 1124–1134, doi:10.3762/bjoc.16.99
- vessel saturated with the vapors of these compounds. The absorbed material changed its PRXD reversibly, returning to its original structure after the absorbed solvent was allowed to evaporate from the sample. The morphology of uncrystallized F-1 was studied by scanning electron microscopy (SEM) analysis
Synthesis of new asparagine-based glycopeptides for future scanning tunneling microscopy investigations
Beilstein J. Org. Chem. 2020, 16, 888–894, doi:10.3762/bjoc.16.80
- cell surfaces for future investigations by combined preparative mass spectroscopy and scanning tunneling microscopy (STM) using soft-landing electrospray beam deposition (ES-IBD), on metal surfaces. Keywords: amino acids; asparagine; carbohydrates; glycopeptides; peptidomimetics; Introduction
The use of isoxazoline and isoxazole scaffolding in the design of novel thiourea and amide liquid-crystalline compounds
Beilstein J. Org. Chem. 2020, 16, 175–184, doi:10.3762/bjoc.16.20
- synthetizing new thioureas and amides by the installation of mesogenic cores derived from isoxazoline and isoxazole scaffolds and 4-n-alkoxybenzoic acid with liquid crystal properties. The liquid crystal properties of the compounds were investigated by polarized optical microscopy analysis (POM) and
Synthesis, liquid crystalline behaviour and structure–property relationships of 1,3-bis(5-substituted-1,3,4-oxadiazol-2-yl)benzenes
Beilstein J. Org. Chem. 2020, 16, 149–158, doi:10.3762/bjoc.16.17
- perfluoroalkyl as terminal chains were synthesized and characterized. Liquid crystal properties of the synthesized compounds have been investigated by polarizing optical microscopy, differential scanning calorimetry and X-ray diffraction techniques. Conformation effects of the synthesized products on the dipole
- compounds 2 and 4 is constituted by a rigid core (three aromatic rings) to which are attached the terminal chains. Based on this structure, some liquid crystalline mesophases were expected. Differential scanning calorimetry (DSC), polarized optical microscopy (POM) and X-ray diffraction pattern analysis
- intermediate phase between 118.0 °C and 138.4 °C in heating and between 96.5 °C and 121.1 °C in cooling, indicating a remarkable stabilization in a temperature range of 20 °C. Polarized optical microscopy (POM) In order to achieve a further illustration of the liquid crystal behavior, POM observations were
Potent hemithioindigo-based antimitotics photocontrol the microtubule cytoskeleton in cellulo
Beilstein J. Org. Chem. 2020, 16, 125–134, doi:10.3762/bjoc.16.14
- network within cells treated with HITubs and documented the resulting disruption of the physiological MT network integrity, and consequently also changes in cell morphology by confocal microscopy. Cells exposed to HITub-4 (1 μM) in the dark or under λ = 530 nm illumination (to maintain exclusively Z
- antiproliferative potencies at λ = 450 and 530 nm/dark conditions (75 ms pulsing every 15 s). b) EC50 values of HITubs from cellular antiproliferation assays under dark conditions and at λ = 450 nm. The ratio of lit/dark EC50 values shows the fold change in photoswitchable bioactivity. Confocal microscopy images of
Influence of the cis/trans configuration on the supramolecular aggregation of aryltriazoles
Beilstein J. Org. Chem. 2019, 15, 2881–2888, doi:10.3762/bjoc.15.282
- and distilled before use. ECD was recorded in the range of 200–400 nm at room temperature by using 10 mm quartz cells. SEM images were taken by a TEM, JEOL JEM 1010 belonging to the Electronic Microscopy Service (SEGAI) of the University of La Laguna, Spain. Compounds 7f, 8f, 9, 10, 11, and 12 were
Chemical tuning of photoswitchable azobenzenes: a photopharmacological case study using nicotinic transmission
Beilstein J. Org. Chem. 2019, 15, 2812–2821, doi:10.3762/bjoc.15.274
- transfected with either wild-type (WT) α4β2 or mutant (E61C) nicotinic acetylcholine receptors [16]. Cells with successful ion channel expression co-expressed YFP visualized using epi-fluorescence microscopy. Cover slips were treated with all trans-1 (0.05 mM in physiological buffer) for 20 min in the dark
A photochemical determination of luminescence efficiency of upconverting nanoparticles
Beilstein J. Org. Chem. 2019, 15, 2671–2677, doi:10.3762/bjoc.15.260
- good agreement with measurements obtained on bulk samples by using integrating spheres [33], and the order of magnitude of the emissive power of a single NP is close to what was achieved by microscopy on nanoparticles of similar composition but at a higher laser power (49 × 10−16 W under 976 nm
Plasma membrane imaging with a fluorescent benzothiadiazole derivative
Beilstein J. Org. Chem. 2019, 15, 2644–2654, doi:10.3762/bjoc.15.257
- (pH 7.4) at room temperature and the coverslips were mounted over glass slides using ProLong Gold Antifade (Invitrogen, OR, USA) according to the manufacturer’s recommendations. These two main samples (of live and fixed cells) were analyzed using confocal microscopy and excited using 405 nm wavelength
- . Afterwards, the cells were washed three times in PBS and the samples were mounted over glass slides by using antifade agent Prolong Gold (Invitrogen, OR, USA) according to the manufacture’s recommendations. The samples were analyzed using confocal microscopy. CellMask was excited at 633 nm wavelength and the
- incubated with BTD-4APTEG (1 μM) in live (A) and (B) and fixed cells (C) and (D). (A) and (C) show the staining distribution of the new dye BTD-4APTEG in the plasma membrane of the cells. (B) and (D) show the normal morphological aspects of the samples by phase contrast microscopy. The dye was found
A new approach to silicon rhodamines by Suzuki–Miyaura coupling – scope and limitations
Beilstein J. Org. Chem. 2019, 15, 2569–2576, doi:10.3762/bjoc.15.250
- application in STED (stimulated emission depletion) microscopy, as sensor molecules for, e.g., ions and as fluorophores for the optical imaging of tumors. Different strategies were already employed for their synthesis. Because of just three known literature examples in which Suzuki–Miyaura cross couplings
- in super-resolution microscopy [1][2][3][4][5][6][7][8] and as probes for targeting various biomolecules [9][10][11][12] or sensors for metal ions [13][14][15][16][17], pH [15], voltage [18] or metabolites [19][20][21][22]. Since our group is interested in synthesizing new tumor tracers for
Probing of local polarity in poly(methyl methacrylate) with the charge transfer transition in Nile red
Beilstein J. Org. Chem. 2019, 15, 2552–2562, doi:10.3762/bjoc.15.248
- fluorescence was used to detect a lipid droplet in monkey aortic smooth muscle cells [16], for visualizing different proteins, such as lactoglobulin, casein and albumin [17]. In fluorescence lifetime imaging microscopy τf as a viable contrast parameter was employed to image lipid droplets in living HeLa cells
Ultrafast processes triggered by one- and two-photon excitation of a photochromic and luminescent hydrazone
Beilstein J. Org. Chem. 2019, 15, 2438–2446, doi:10.3762/bjoc.15.236
- ], drug delivery [8][9], design of molecular machines [10][11][12][13], super resolution microscopy [14][15], together with biological applications, among which photopharmacology is currently gaining increasing attention [16][17][18][19]. Photochromic molecules, which respond to light as an external
Targeted photoswitchable imaging of intracellular glutathione by a photochromic glycosheet sensor
Beilstein J. Org. Chem. 2019, 15, 2380–2389, doi:10.3762/bjoc.15.230
- broad and strong absorption makes the 2D MnO2 nanosheets a potential energy acceptor for the fluorophores which are stacked on the nanosheets plane, leading to the fluorescence quenching through FRET mechanism [32][34]. The transmission electron microscopy (TEM) image of the prepared product revealed
Mono- and bithiophene-substituted diarylethene photoswitches with emissive open or closed forms
Beilstein J. Org. Chem. 2019, 15, 2344–2354, doi:10.3762/bjoc.15.227
- large fluorescence quantum yield, compound SyOTh1 emerged as a candidate for single-molecule based super-resolution fluorescence microscopy. Keywords: diarylethenes; dyes; fluorescence; organic synthesis; photochromism; photoswitching; Introduction Reversibly photoswitchable diarylethenes (DAEs) with
- asymmetric DAEs with oxidized 2-ethylbenzo[b]thiophene-3-yl units have high cycloreversion quantum yields (a desirable feature for super-resolution RESOLFT microscopy), large Stokes shifts and acceptable absorptivity [5]. Yet unknown asymmetric “thiophenylated” DAEs may have unique properties
- to monothiophene and then to bithiophene derivatives). In all cases, asymmetric substitution allowed faster cycloreversion than symmetric substitution, which is a positive effect regarding potential application of these dyes as reversible fluorescent markers in RESOLFT microscopy [5]. Two processes
Synthesis of a dihalogenated pyridinyl silicon rhodamine for mitochondrial imaging by a halogen dance rearrangement
Beilstein J. Org. Chem. 2019, 15, 2333–2343, doi:10.3762/bjoc.15.226
- microscopy [2][3][4][5][6][7][8][9], as direct probes for various biomolecules [10][11][12][13] or as sensors for metal ions [14][15][16][17][18], pH [16], voltage [19] or metabolites [20][21][22][23]. Several attempts were made, partially supported by DFT calculations, to correlate the dyes’ structural
- different silicon rhodamines. Optimization of the HD rearrangement of 19 and subsequent reaction with xanthone 17 to the silicon rhodamine dye 15. Supporting Information Synthesis of dye 15, its optical characterization and detailed information on microscopy experiments, including videos showing
Fluorescent phosphorus dendrimers excited by two photons: synthesis, two-photon absorption properties and biological uses
Beilstein J. Org. Chem. 2019, 15, 2287–2303, doi:10.3762/bjoc.15.221
- widespread popularity of TPE (also named TPA, for two-photon absorption) in the biology community, with on one side, the advent of two-photon excitation fluorescence microscopy [4], even for research clinical uses [5], and on the other side with the discovery of the TPA properties of quantum dots (inorganic
Aggregation-induced emission effect on turn-off fluorescent switching of a photochromic diarylethene
Beilstein J. Org. Chem. 2019, 15, 2204–2212, doi:10.3762/bjoc.15.217
- , fluorescence switching for molecular level recording [4], multiple-fluorescence for logic circuits [5] as well as biological applications [6] and super-resolution microscopy for bio-imaging [7][8]. The fluorescence switching in solid state is attracting much attention from both scientific and technological
Bipolenins K–N: New sesquiterpenoids from the fungal plant pathogen Bipolaris sorokiniana
Beilstein J. Org. Chem. 2019, 15, 2020–2028, doi:10.3762/bjoc.15.198
- research was undertaken with the assistance of resources and services from the National Computational Infrastructure (NCI), which is supported by the Australian Government. Authors acknowledge the facilities of Microscopy Australia at the Centre for Microscopy, Characterisation & Analysis, The University
Archangelolide: A sesquiterpene lactone with immunobiological potential from Laserpitium archangelica
Beilstein J. Org. Chem. 2019, 15, 1933–1944, doi:10.3762/bjoc.15.189
- , the endoplasmic reticulum was visualized by transfection with a plasmid DNA coding mCherry-ER (0.5 µg) using Fugene HD (Promega, USA; DNA/Fugene HD = 1:3). Fluorescence microscopy The intracellular localization of compound 5 was studied by real-time live-cell fluorescence microscopy using an inverse
- sesquiterpene lactones archangelolide (1) and trilobolide (2). Intracellular localization of archangelolide-dansyl (5) in human cells from osteosarcoma (U-2 OS). A, C) Bright-field images; B, D) fluorescence microscopy of living cells treated with 1 µM concentration of compound 5 for 90 min. Co-localization of
- dansylarchangelolide 5 with a marker of endoplasmic reticulum (top row) and with a mitochondrial marker (bottom row) in human cells from osteosarcoma (U-2 OS). A, E) Bright-field images. Fluorescence microscopy of living cells treated with 1 µM concentration of compound 5 (90 min; images B and F) and a mitochondria
Morphology-tunable and pH-responsive supramolecular self-assemblies based on AB2-type host–guest-conjugated amphiphilic molecules for controlled drug delivery
Beilstein J. Org. Chem. 2019, 15, 1925–1932, doi:10.3762/bjoc.15.188
- -assembly and the size of β-CD-BM2-based supramolecular self-assemblies under neutral and acidic pH were first investigated by employing transmission electron microscopy (TEM) and dynamic light scattering (DLS). The prepared β-CD-BM2 were dissolved under neutral pH solution to form FSSAs. TEM revealed that
- -loaded supramolecular self-assemblies Confocal laser scanning microscopy (CLSM) was further utilized to confirm the intracellular uptake of DOX-loaded FSSAs (Figure 6). The PC-3 cells treated with DOX-loaded FSSAs indicated Hoechst 33342 blue fluorescence in their nuclei and DOX red fluorescence in their
Nanopatterns of arylene–alkynylene squares on graphite: self-sorting and intercalation
Beilstein J. Org. Chem. 2019, 15, 1848–1855, doi:10.3762/bjoc.15.180
- , Uniwersytet Wrocławski, ul. F. Joliot-Curie 14, 50-383 Wrocław, Poland 10.3762/bjoc.15.180 Abstract Supramolecular nanopatterns of arylene–alkynylene squares with side chains of different lengths are investigated by scanning tunneling microscopy at the solid/liquid interface of highly oriented pyrolytic
- and non-planar coronoid polycyclic aromatic hydrocarbons (i.e., butyloxy-substituted kekulene and octulene derivatives) are found to be able to intercalate into the intramolecular nanopores. Keywords: macrocycles; scanning tunneling microscopy; self-assembled monolayers; self-sorting; solid/liquid
- tunneling microscopy (STM). Throughout all STM images, surface regions covered by arylene–alkynylene backbones and (intermolecularly interdigitating) alkoxy side chains appear in bright and dark colors, which indicate high and low tunneling currents, respectively [31]. In most of our STM images, we achieve
Norbornadiene-functionalized triazatriangulenium and trioxatriangulenium platforms
Beilstein J. Org. Chem. 2019, 15, 1815–1821, doi:10.3762/bjoc.15.175
- as realized in compound 1. Consequently, future surface chemistry investigations will be performed with compound 1 including the TATA platform and an ethynyl spacer. STM Measurements The adsorption behaviour of the NBD 1a on Au(111) surfaces was studied by scanning tunnelling microscopy (STM) at room
Synthesis and conformational preferences of short analogues of antifreeze glycopeptides (AFGP)
Beilstein J. Org. Chem. 2019, 15, 1581–1591, doi:10.3762/bjoc.15.162
- into the ice lattice [12], others investigated the adsorption process on different surfaces via atomic force microscopy [10][13][14]. The antifreeze activity has been correlated with long-range perturbation of hydration dynamics [15]. Latest molecular dynamics simulations suggest that AFGP reversibly
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