Pyridinium based amphiphilic hydrogelators as potential antibacterial agents

• Sayanti Brahmachari,
• Sisir Debnath,
• Sounak Dutta and
• Prasanta Kumar Das

Beilstein J. Org. Chem. 2010, 6, 859–868, doi:10.3762/bjoc.6.101

• microscopy (FESEM), atomic force microscopy (AFM), photoluminescence, FTIR studies, X-ray diffraction (XRD) and 2D NOESY experiments were carried out to elucidate the different non-covalent interactions responsible for the self-assembled gelation. The formation of three-dimensional supramolecular aggregates

• fluorescence spectroscopy. The topographical features of the soft matter were visualized using different microscopic techniques (scanning electron microscopy (SEM), atomic force microscopy (AFM)). Interestingly, these compounds were found to show excellent antibacterial activity against Gram-positive and Gram

• architecture of 2 at the aggregated state was further confirmed by Atomic Force Microscopic (AFM) images. Two and three dimensional AFM images of xerogel 2 (Figure 3c, d) showed the involvement of fibrillar networks in self-assembled hydrogelation. The dimension of the fibril network observed in the AFM image

Self-assembled ordered structures in thin films of HAT5 discotic liquid crystal

• Piero Morales,
• Jan Lagerwall,
• Paolo Vacca,
• Sabine Laschat and
• Giusy Scalia

Beilstein J. Org. Chem. 2010, 6, No. 51, doi:10.3762/bjoc.6.51

• compared to the bulk situation, where the same material crystallizes into a polymorphic structure at 68 °C. Keywords: AFM; discotic liquid crystals; hexapentyloxytriphenylene; self-organization; thin films; Introduction Discotic liquid crystals are an interesting type of organic semiconductors that allow

• ensured thinner films had a uniformly black aspect. The origin of the black background is the extremely small thickness of the LC film, giving negligible effective birefringence, even for a director in planar orientation. The analysis of these regions thus relied mainly on atomic force microscopy (AFM

• ellipse in the top and bottom pictures of Figure 2. It was possible to localize these structures by AFM as shown in Figure 3. Here an example with overall diameter in the order of 1.5–2 μm (similar to the lines detected optically) is shown, together with small elongated aggregates. The substrate roughness

New diarylmethanofullerene derivatives and their properties for organic thin- film solar cells

• Daisuke Sukeguchi,
• Surya Prakash Singh,
• Mamidi Ramesh Reddy,
• Hideyuki Yoshiyama,
• Rakesh A. Afre,
• Yasuhiko Hayashi,
• Hiroki Inukai,
• Tetsuo Soga,
• Shuichi Nakamura,
• Norio Shibata and
• Takeshi Toru

Beilstein J. Org. Chem. 2009, 5, No. 7, doi:10.3762/bjoc.5.7

• observed in the case of PCBM [32][33][34], which possibly makes the conjugation length of P3HT longer. AFM measurements were performed on P3HT:1a and P3HT:PCBM films with different annealing temperatures. Different results were obtained between P3HT/1a and P3HT/PCBM: substantially similar low roughness

• values were observed in the AFM image of P3HT/1a annealed at 100, 130, 140 °C (r.m.s. = 0.9–1.1 nm). On the other hand, films of P3HT/PCBM showed similar roughness at 130 and 140 °C (r.m.s. = 1.4–1.6 nm), but a coarser surface was observed at 100 °C (r.m.s. = 2.2–2.6 nm). The P3HT/PCBM cell showed the

• obtained at a lower annealing temperature (100 °C). Their spectral responsivities and the AFM measurements suggested a change of the P3HT alignment depending on the annealing temperatures. These observations will lead the way to further development of highly efficient acceptors for organic thin-film solar

Synthesis of thienyl analogues of PCBM and investigation of morphology of mixtures in P3HT

• Fukashi Matsumoto,
• Kazuyuki Moriwaki,
• Yuko Takao and
• Toshinobu Ohno

Beilstein J. Org. Chem. 2008, 4, No. 33, doi:10.3762/bjoc.4.33

• thieno[3,2-b]thiophene (3c, 3d) were synthesized and characterized. The morphology of the thin films prepared from the mixtures of these methanofullerenes with regioregular poly(3-hexylthiophene) (P3HT) was investigated by AFM measurement and UV-Vis absorption spectroscopy. A solubility test of these

• hetero films of these novel methanofullerenes were spin coated on glass substrates and were characterized by using AFM and UV-Vis absorption spectroscopy in order to study and compare their morphological features. 3-BThCBM (3b) and TThCBM (3c) were excluded because their high-concentration solutions

• glass plate and dried for 24 h at room temperature under vacuum. Tapping-mode AFM measurements were performed on a film area of 500 × 500 nm. All films had a very flat surface and almost the same roughness (r.m.s. value of 0.2–0.24 nm). However in the phase image (Figure 2), (A) PCBM and (B) ThCBM