Browsing by Subject "Molecular Structure"

Now showing 1 - 4 of 4

Open Access
Antibacterial electrospun nanofibers from triclosan/cyclodextrin inclusion complexes
(Elsevier, 2014) Celebioglu A.; Umu, O. C. O.; Tekinay, T.; Uyar, Tamer
The electrospinning of nanofibers (NF) from cyclodextrin inclusion complexes (CD-IC) with an antibacterial agent (triclosan) was achieved without using any carrier polymeric matrix. Polymer-free triclosan/CD-IC NF were electrospun from highly concentrated (160% CD, w/w) aqueous triclosan/CD-IC suspension by using two types of chemically modified CD; hydroxypropyl-beta-cyclodextrin (HPβCD) and hydroxypropyl-gamma-cyclodextrin (HPγCD). The morphological characterization of the electrospun triclosan/CD-IC NF by SEM elucidated that the triclosan/HPβCD-IC NF and triclosan/HPγCD-IC NF were bead-free having average fiber diameter of 520±250nm and 1100±660nm, respectively. The presence of triclosan and the formation of triclosan/CD-IC within the fiber structure were confirmed by 1H-NMR, FTIR, XRD, DSC, and TGA studies. The initial 1:1molar ratio of the triclosan:CD was kept for triclosan/HPβCD-IC NF after the electrospinning and whereas 0.7:1molar ratio was observed for triclosan/HPγCD-IC NF and some uncomplexed triclosan was detected suggesting that the complexation efficiency of triclosan with HPγCD was lower than that of HPβCD. The antibacterial properties of triclosan/CD-IC NF were tested against Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus aureus) bacteria. It was observed that triclosan/HPβCD-IC NF and triclosan/HPγCD-IC NF showed better antibacterial activity against both bacteria compared to uncomplexed pure triclosan.
Open Access
Self-assembled template-directed synthesis of one-dimensional silica and titania nanostructures
(2011) Acar H.; Garifullin, R.; Güler, Mustafa O.
Mineralized biological materials such as shells, skeleton, and teeth experience biomineralization. Biomimetic materials exploit the biomineralization process to form functional organic-inorganic hybrid nanostructures. In this work, we mimicked the biomineralization process by the de novo design of an amyloid-like peptide that self-assembles into nanofibers. Chemically active groups enhancing the affinity for metal ions were used to accumulate silicon and titanium precursors on the organic template. The self-assembly process and template effect were characterized by CD, FT-IR, UV-vis, fluorescence, rheology, TGA, SEM, and TEM. The self-assembled organic nanostructures were exploited as a template to form high-aspect-ratio 1-D silica and titania nanostructures by the addition of appropriate precursors. Herein, a new bottom-up approach was demonstrated to form silica and titania nanostructures that can yield wide opportunities to produce high-aspect-ratio inorganic nanostructures with high surface areas. The materials developed in this work have vast potential in the fields of catalysis and electronic materials. © 2011 American Chemical Society.
Open Access
Synthesis and anticancer activity evaluation of some benzothiazole-piperazine derivatives
(Bentham Science Publishers B.V., 2015) Gurdal, E.E.; Buclulgan, E.; Durmaz I.; Cetin-Atalay, R.; Yarim, M.
Synthesis, characterization and cytotoxic activities of ten benzothiazole-piperazine derivatives were reported. In vitro cytotoxic activities of compounds were screened against hepatocellular (HUH-7), breast (MCF-7) and colorectal (HCT-116) cancer cell lines by sulphorhodamine B assay. Based on the GI50 values of the compounds, most of the benzothiazole-piperazine derivatives are active against HUH-7, MCF-7 and HCT-116 cancer cell lines. Aroyl substituted compounds 1h and 1j were found to be the most active derivatives. In addition, further investigation of compounds 1h and 1j by Hoechst staining and FACS revealed that these compounds cause apoptosis by cell cycle arrest at subG1 phase. © 2015 Bentham Science Publishers.
Open Access
Synthesis of novel substituted purine derivatives and identification of the cell death mechanism
(Elsevier Masson SAS, 2015) Demir, Z.; Guven, E.B.; Ozbey, S.; Kazak, C.; Atalay, R.C.; Tuncbilek, M.
Novel substituted adenine and purine derivatives were designed and synthesized.Compound 36 displayed the greatest cytotoxic activity with IC50 less than 1 1/4M.36 induces senescence associated cell death, which was demonstrated with SA2-Gal assay. © 2014 Elsevier Masson SAS.