ABSTRACT
Electron-deficient corannulene derivatives incorporating cyano and imide groups into the corannulene core were synthesized, which showed low LUMO (lowest unoccupied molecular orbital) levels and dense convex-concave packing structures in single crystals. These two features help to realize the first n-channel organic field-effect transistors (OFETs) in air based on corannulene derivatives.
ABSTRACT
A novel molecularly imprinted photonic polymer (MIPP) using maleic anhydride modified ß-cyclodextrin (ß-CD) and acrylic acid as functional monomers has been presented for amino acid sensing. Reactive ß-CD monomer carrying vinyl carboxylic acid functional groups was first synthesized. MIPP was fabricated by filling precursor solution into the interstitial spaces of polystyrene photonic crystal templates, followed by a thermal polymerization at 55 °C. Characterization showed that the MIPP possessed an opal photonic crystal structure. This ß-CD-based MIPP could undergo a swelling change from 590 nm to 704 nm and still retain the molecular imprinting recognition ability during the sensing of L-phenylalanine (L-Phe). A function relationship was found between the diffraction wavelength shift and the logarithm of L-Phe concentration in the range of 10(-8)M to 10(-4)M at pH 6. A wavelength shift of 114 nm for L-Phe was observed within 30s, whereas there were no obvious shifts for d-Phe, L-tyrosine and L-tryptophan, indicating that the ß-CD-based MIPP had high specificity and rapid response to L-Phe. The developed MIPP sensor has been applied to detect L-Phe in compound amino acid injection sample.
Subject(s)
Molecular Imprinting/methods , Phenylalanine/analysis , Photons , beta-Cyclodextrins/chemistry , Acrylates/chemistry , Crystallization , Hydrogen-Ion Concentration , Maleic Anhydrides/chemistry , Polymerization , Polystyrenes/chemistry , Sensitivity and Specificity , Stereoisomerism , TemperatureABSTRACT
OBJECTIVE: To investigate the alkaloids from the stem of Artabotrys hainanensis. METHOD: Compounds in plant extracts were separated by silica gel and sephadex LH-20 column chromatography. Chemical structures were elucidated by chemical and spectral analyses including UV, 1H-NMR, 13C-NMR, ESIMS and ESI-MS-MS. RESULT: Eight alkaloids were isolated and identified as spinosine (1), 3-hydroxynornuciferine (2), juzirine (3), artabotrine (4), liridine (5), assimilobine (6), isococlaurine (7), N-demethylarmepavine (8). CONCLUSION: All alkaloids were isolated from this plant for the first time and compounds 1, 3, 7 and 8 were isolated from genus Artabotrys for the first time.
Subject(s)
Alkaloids/isolation & purification , Annonaceae/chemistry , Plants, Medicinal/chemistry , Alkaloids/chemistry , Berberine Alkaloids/chemistry , Berberine Alkaloids/isolation & purification , Isoquinolines/chemistry , Isoquinolines/isolation & purification , Plant Leaves/chemistry , Plant Stems/chemistryABSTRACT
AIM: To elucidate the molecular mechanism of granulocytic differentiation of human promyelocytic leukemia HL-60 cells induced by all-trans-retinoic acid (ATRA). METHODS: Flow cytometry was used to determine the cell cycle changes of HL-60 cells upon ATRA treatment. Gene expression profiles of HL-60 cells induced by 1 mumol.L-1 ATRA were obtained by using cDNA microarrays containing 9,984 genes and expressed sequence tags (ESTs). RESULTS: Cell cycle analysis showed that 48%-73% of cells were arrested at G1/G0 phase upon ATRA treatment; cDNA microarray results demonstrated that the expression of genes encoding adhesion molecules, tissue remodeling proteins, transporters and ribosomal proteins were up-regulated in ATRA treated of HL-60 cells. Several genes involved in oxidase activation pathway were also differentially expressed. CONCLUSION: ATRA treatment induced growth arrest and differentiation in HL-60 cells, which is associated with regulation of the oxidase activation pathway and the expression of tissue remodeling proteins.
