RESUMO
We have demonstrated that one-dimensional supramolecular dye assemblies with a uniform diameter can be created by utilizing schizophyllan (SPG) as a one-dimensional host. In the supramolecular nanofibers, the dye molecules are assembled into the different aggregation modes depending on the preparation procedures. The findings establish that SPG is useful for creating the supramolecular nanofibers, where temporal superstructures can be stabilized by the SPG-specific helical higher-order structure. [structure: see text].
RESUMO
(1-->3)-beta-D-Glucans having various functional appendages (lactoside, ferrocene, pyrene, and porphyrin) can be prepared in an convenient, quantitative, and regioselective manner through regioselective bromination-azidation of curdlan to afford 6-azido-6-deoxycurdlan followed by chemoselective [3+2]-cycloadditions with various functional modules bearing a terminal alkyne group. The ability to monitor reaction conversions is an additional advantage of this synthetic approach over the conventional direct modifications on polysaccharides; the reaction can be readily monitored based on the intensity of azido peaks in the in situ attenuated total reflection infrared spectra.
Assuntos
beta-Glucanas/síntese química , Alcinos/química , Azidas/química , Ressonância Magnética Nuclear Biomolecular , Proteoglicanas , Espectroscopia de Infravermelho com Transformada de Fourier , beta-Glucanas/químicaRESUMO
Schizophyllan interacts with various 1,4-diphenylbutadiyne derivatives to induce their chirally-twisted packing. A series of referential experiments using other polysaccharides (amylose, pullulan, dextran, etc.) and a carbohydrate-appended detergent (dodecyl-beta-d-glucopyranoside) indicates that these 1,4-diphenylbutadiyne derivatives are accommodated within a tubular cavity constructed by a helical superstructure of schizophyllan. In these 1,4-diphenylbutadiyne derivatives, 1,4-bis(p-propionamidophenyl)butadiyne can be easily polymerized through UV-irradiation, in which schizophyllan acts as a one-dimensional mold to produce the corresponding poly(diacetylene)s with fibrous morphologies. Detailed investigations on this unique approach to prepare the nanofibers revealed that it includes two individual processes, that is, 1) UV-mediated polymerization of encapsulated 1,4-bis(p-propionamidophenyl)butadiyne to produce immature nanofibers and 2) their reorganization through hydrophobic interfiber interactions into ordered nanofibers. The other 1,4-diphenylbutadiyne derivatives could not be polymerized through UV-irradiation, indicating that the p-propionamido-functionalities play substantial roles for a suitable packing of the monomer for the polymerization. The other 1,4-diphenylbutadiyne derivatives, however, can be also polymerized through gamma-ray irradiation in the presence of schizophyllan to give the corresponding poly(diacetylene)-nanofibers, emphasizing the wide applicability of the schizophyllan-based strategy for polymerization of various 1,4-diphenylbutadiyne derivatives.
Assuntos
Acetileno/análogos & derivados , Nanoestruturas/efeitos da radiação , Polímeros/química , Sizofirano/química , Acetileno/química , Butadienos/síntese química , Butadienos/química , Microscopia Eletrônica de Transmissão , Estrutura Molecular , Nanoestruturas/ultraestrutura , Polímero Poliacetilênico , Poli-Inos , Análise Espectral , EstereoisomerismoRESUMO
Schizophyllan having folate-appendages was synthesized from native schizophyllan through NaIO(4)-oxidation and the subsequent reductive amination in aqueous ammonia followed by amido-coupling with folic acid. The resulting folate-appended schizophyllan can form stable complex with poly(dA), show specific affinity toward folate binding protein, and mediate effective antisense activity in cancer cells.
Assuntos
Ácido Fólico/química , Oligonucleotídeos Antissenso/farmacologia , Sizofirano/química , Sequência de Bases , Proteínas de Transporte/síntese química , Proteínas de Transporte/farmacologia , Receptores de Folato com Âncoras de GPI , Ácido Fólico/farmacologia , Humanos , Células KB , Receptores de Superfície Celular , Sizofirano/farmacologia , Fatores de TempoRESUMO
We here demonstrate the creation of novel poly(aniline) (PANI) nanofiber structures by a polymer wrapping method using schizophyllan (SPG). Mannose-modified SPG can also wrap PANIs to give nanofibers having a lectin affinity. This interaction is applicable to designing novel PANI/protein composites. The results establish that SPG can act as a novel "host" to assemble PANIs into one-dimensional superstructures. [reaction: see text]
Assuntos
Compostos de Anilina/síntese química , Sizofirano/química , Compostos de Anilina/química , Lectinas/química , Manose/química , Nanoestruturas , Ligação ProteicaRESUMO
Schizophyllans carrying beta-lactoside and alpha-mannoside appendages were prepared from native schizophyllan through NaIO4 oxidation followed by reductive amination using aminoethyl-beta-lactoside and alpha-mannoside, respectively. The resulting schizophyllans form stable macromolecular complexes with polynucleotides, such as poly(C) and poly(dA). Specific affinity between these macromolecular complexes and saccharide-binding proteins was demonstrated by surface plasmon resonance and agarose gel staining assays. beta-lactoside-appended schizophyllan enhanced an antisense activity in hepatocytes which express lactoside-binding proteins on their cell surfaces.
Assuntos
Sistemas de Liberação de Medicamentos/instrumentação , Sistemas de Liberação de Medicamentos/métodos , Oligonucleotídeos Antissenso/administração & dosagem , Oligossacarídeos/química , Sizofirano/química , Contagem de Células , Dicroísmo Circular , Eletroforese em Gel de Ágar , Glicosídeos/química , Humanos , Cinética , Substâncias Macromoleculares/síntese química , Substâncias Macromoleculares/química , Poli A/química , Poli C/química , Sensibilidade e Especificidade , Sizofirano/síntese química , Ressonância de Plasmônio de SuperfícieRESUMO
Single-walled carbon nanotubes can be entrapped within a helical superstructure composed of schizophyllan bearing lactoside-appendages to show an excellent water-solubility as well as a specific lectin-affinity.