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371.
372.
Cuiling Du Dr. Jie Zhao Dr. Jinbo Fei Dr. Liang Gao Wei Cui Dr. Yang Yang Prof. Dr. Junbai Li 《化学:亚洲杂志》2013,8(4):736-742
A reactive template method was used to fabricate alginate‐based hydrogel microcapsules. The uniform and well‐dispersed hydrogel capsules have a high drug loading capacity. After they are coated by a folate‐linked lipid mixture on the surface, the capsules possess higher cell uptake efficiency by the molecule recognition between folate and the folate‐receptor overexpressed by the cancer cells. Moreover, in this bioconjugate, the lipid could remarkably reduce the release rate of hydrophilic doxorubicin from the hydrogel microcapsules and encapsulate the hydrophobic photosensitizer hypocrellin B. The biointerfaced capsules could be used as drug carriers for combined treatment against cancer cell proliferation in vitro; this was much more effective than chemotherapy or photodynamic therapy alone. 相似文献
373.
Rui Feng Yong Zhang He Li Dan Wu Xiaodong Xin Sen Zhang Haiqin Yu Qin Wei Bin Du 《Analytica chimica acta》2013
Nano-montmorillonites belong to aluminosilicate clay minerals with innocuity, high specific surface area, ion exchange, and favorable adsorption property. Due to the excellent properties, montmorillonites can be used as labels for the electrochemical immunosensors. In this study, nano-montmorillonites were converted to sodium montmorillonites (Na-Mont) and further utilized for the immobilization of thionine (TH), horseradish peroxidase (HRP) and the secondary anti-zeranol antibody (Ab2). The modified particles, Na-Mont-TH-HRP-Ab2 were used as labels for immunosensors to detect zeranol. This protocol was used to prepare the immunosensor with the primary antibody (Ab1) immobilized onto the nanoporous gold films (NPG) modified glassy carbon electrode (GCE) surface. Within zeranol concentration range (0.01–12 ng mL−1), a linear calibration plot (Y = 0.4326 + 8.713 X, r = 0.9996) was obtained with a detection limit of 3 pg mL−1 under optimal conditions. The proposed immunosensor showed good reproducibility, selectivity, and stability. This new type of immunosensors with montmorillonites and NPG as labels may provide potential applications for the detection of zeranol. 相似文献
374.
The indium-mediated Barbier-type allylation reaction of aldehydes with allyl bromide, which gives corresponding homoallyl alcohols, was investigated. The reaction medium and the effects of substituents were discussed in detail. The results showed that various aldehydes, including aromatic, heterocyclic, and aliphatic aldehydes, with different substituents could all react well with excellent yields of 91–97% in aqueous tetrahydrofuran at room temperature within about 1 h.
375.
Copper-catalyzed selective methylthiomethylation of 1,4-disubstituted 1,2,3-triazole phenols using DMSO as a methylthiomethylation reagent was achieved. Controlled by the triazole ring, the ortho-phenolic hydroxyl in N(1) aryl can be selectively methylthiomethylated, generating functionalized 1,4-disubstituted 1,2,3-triazoles bearing aryl methylthiomethyl ether fragment. 相似文献
376.
A general and efficient synthetic method of 1,3-bis(phenylseleno)-2-propanol by reducing diphenyl diselenides with sodium borohydride in basic environment and then reacting with epichlorohydrin are described. 相似文献
377.
Ranran Du Bingbing Suo Huixian Han Yibo Lei Gaohong Zhai 《International journal of quantum chemistry》2013,113(22):2464-2470
Potential energy curves of 22 electronic states of RhN have been calculated by the complete active space second‐order perturbation theory method. The X1Σ0+ is assigned as the ground state, and the first excited state a3Π0+ is 978 cm?1 higher. The 1Δ(I) and B1Σ+ states are located at 9521 and 13,046 cm?1 above the ground state, respectively. The B1Σ+ state should be the excited state located 12,300 cm?1 above the ground state in the experimental study. Moreover, two excited states, C1Π and b3Σ+, are found 14,963 and 15,082 cm?1 above the X1Σ+ state, respectively. The transition C1Π1–X1Σ0+ may contribute to the experimentally observed bands headed at 15,071 cm?1. There are two excited states, D1Δ and E1Σ+, situate at 20,715 and 23,145 cm?1 above the X1Σ+ state. The visible bands near 20,000 cm?1 could be generated by the electronic transitions D1Δ2–a3Π1 and E1Σ+0–X1Σ+0 because of the spin–orbit coupling effect. © 2013 Wiley Periodicals, Inc. 相似文献
378.
The equilibrium geometries and vibrational frequencies of the ionic liquid 1-butyl-3-methylimidazolium cation and the alanine anion [BMIM][Ala] are studied using density functional theory (DFT) at the B3PW91/6-311+G(d,p) leve1. The most stable structures of the anion, the cation, and the ion pairs are obtained and characterized, and the geometry parameters of the ion pairs confirm the presence of a hydrogen bonding interaction between the anion and the cation. Natural bond orbital (NBO) analysis is also performed to analyze the atomic charge distribution and charge transfer in the [BMIM]+ cation and [BMIM][Ala] ionic liquids. The results show that there are the electrostatic interaction and multiple hydrogen bond interactions between the cation and the anion of the ionic liquids, and the stability of the ground state of the ion pairs mostly results from the hydrogen bonding between the lone pairs of O atoms in the anion and H in the imidazole cycle of the cation. There are some changes in microstructures and the charge distribution during the formation of the ion pairs. 相似文献
379.
A green, efficient method for the synthesis of various 2-aryl-benzimidazoles in the presence of hypervalent iodine as the oxidant at room temperature under solvent-free conditions is reported. The salient features of this method include mild conditions, short reaction times (3–5 min), excellent yields, and simple procedure. 相似文献
380.
Mediated by samarium diiodide, 1-(benzotriazole-1-yl)alkyl esters 1 underwent cross-coupling with aldehydes or ketones to afford β-(benzotriazole-1-yl)alcohols 2 exclusively with the selective removal of acyloxy over benzotriazolyl. 相似文献