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Li P.,Guangxi University for Nationalities | Wang T.,Guangxi University for Nationalities | Lei F.,Guangxi University for Nationalities | Lei F.,Guangxi Provincial Key Laboratory of Forest Products Chemistry and Engineering | And 4 more authors.
Polymer International

A novel method for the separation of berberine hydrochloride has been developed. Berberine hydrochloride molecularly imprinted polymers were prepared by suspension polymerization in the aqueous phase using berberine hydrochloride as the template, methyl acrylic acid as a functional monomer, and ethylene glycol maleic rosinate acrylate (which contains a phenanthrene ring skeleton) and ethylene glycol dimethacrylate as combinatorial crosslinkers. The imprinted polymers were successfully used as a selective stationary phase in high-performance liquid chromatography. Separation performance of the chromatographic column was determined from the selectivity (evaluated by separation factor) and sorption selectivity (evaluated by imprinting factor) of the molecularly imprinted and non-imprinted polymers towards the template. The optimum conditions to maximize separation and imprinting factors were investigated. Acetic acid-methanol solution (0.05% v/v) was selected as the optimum mobile phase, while 0.2 mL min-1 was chosen as the optimized flow rate for selective separation of berberine hydrochloride. The highest imprinting and separation factors obtained were 1.924 and 18.52, respectively. Simultaneously, the chromatographic column backpressure was stable and showed good permeability. The chromatographic column was used to separate effectively template molecules from coptis root extract and other analogues. Such chromatographic columns with high selectivity can be used to selectively separate berberine hydrochloride from other compounds. © 2014 Society of Chemical Industry. Source

Feng Y.,Guangxi University for Nationalities | Su Z.-X.,Guangxi University for Nationalities | Sun L.,Guangxi University for Nationalities | Liu S.-G.,Guangxi University for Nationalities | And 5 more authors.
Acta Polymerica Sinica

Thieno [2, 3-b] thiophene-diketopyrrolopyrrole (DPPTTZ), a novel cross-conjugated electrondeficient unit, has been synthesized. This unit was brominated and then copolymerized with 2, 5-bis(trimethylstannyl) thiophene, 2, 5-bis (trimethylstannyl) selenophene and 2, 5-bis (trimethyl-stannyl)-N-methylpyrrole respectively, via Stille polymerzation, to form three donor-acceptor (D-A) type copolymers, poly {2,5-bis (2-octyldodecyl)-3-[5-(thiophen-2, 5-yl) thieno [2, 3-6] thiophen-2-yl] - 6-(thieno [2, 3-6] thiophen-2,5-yl) pyrrolo[3,4-c]pyrrole-1,4(2H,5H)-dione} (pDPPTTZ-T),poly j 2,5-bis(2-octyldodecyl) - 3-[5-(selenophen-2,5-yl) thieno [2,3-6] thiophen-2-yl]-6-(thieno [2,3-b] thiophen-2,5-yl) pyrrolo[3,4-c] pyrrole-1,4(2H,5H)-dione} (pDPPTTZ-Se) and poly 12,5-bis(2-octyldodecyl)-3-[5-(N-methylpyrrole-2, 5-yl) thieno[2,3-6] thiophen-2-yl]-6-(thieno[2,3-6] thiophen-2,5-yl) pyrrolo[3,4-c] pyrrole-1,4(2H,5H)-dione} (pDPPTTZ-Py). These polymers exhibit deep HOMO energy levels (-5.26 ∼-5.37 eV),leading to high open-circuit voltage (0. 68-0.81 V) in OPV devices, and good stability of the devices towards atmospheric oxygen. The UV-Vis spectra show broad features with long-wavelength absorption maximum around 620 nm and optical band gap of 1. 86,1. 83 and 1. 85 eV for pDPPTTZ-T, pDPPTTZ-Se and pDPPTTZ-Py respectively, which give polymers a good overlap of solar spectrum. Bulk heterojunction solar cells were fabricated by blending these polymers with [6,6]-phenyl-C71-butiric acid methyl ester (PC71 MB), and the power conversion efficiency (PCE) reaches 3. 05% for the as cast pDPPTTZ-T: PCBM-based device without optimization, under simulated AM 1.5 G irradiation of 100 mW/cm2. Source

Zhang W.-M.,Guangxi University for Nationalities | Zhang W.-M.,Guangxi Provincial Key Laboratory of Forest Products Chemistry and Engineering | Feng Y.,Guangxi University for Nationalities | Diao K.-S.,Guangxi University for Nationalities | And 6 more authors.
Gaodeng Xuexiao Huaxue Xuebao/Chemical Journal of Chinese Universities

Novel materials for organic field effect transistor-poly(indenofluorene-triphenylamine) (pIFTPA 1-4) were synthesized and characterized by NMR and gel permeation chromatography (GPC). The organic field effect transistors (OFETs) based on these polymers were investigated. It was observed that stable amorphous thin films were formed in the devices, with better charge-carrier mobility than poly(triphenyl-amine) (pTPA). In four polymers synthesized, pIFTPA 4 presents the highest hole mobility, as high as 4×10-2 cm2/(V·s), with an ON/OFF ratio in excess of 106. Source

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