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991.
Cheng Tang Xiaoming Chen Hua Yao Haiyan Yin Xiaoping Ma Mingji Jin Xin Lu Quntao Wang Kun Meng Qipeng Yuan 《Molecules (Basel, Switzerland)》2021,26(11)
The purpose of this study was to develop mixed polymeric micelles with high drug loading capacity to improve the oral bioavailability of icaritin with Soluplus® and Poloxamer 407 using a creative acid-base shift (ABS) method, which exhibits the advantages of exclusion of organic solvents, high drug loading and ease of scaling-up. The feasibility of the ABS method was successfully demonstrated by studies of icaritin-loaded polymeric micelles (IPMs). The prepared IPMs were characterized to have a spherical shape with a size of 72.74 ± 0.51 nm, and 13.18% drug loading content. In vitro release tests confirmed the faster release of icaritin from IPMs compared to an oil suspension. Furthermore, bioavailability of icaritin in IPMs in beagle dogs displayed a 14.9-fold increase when compared with the oil suspension. Transcellular transport studies of IPMs across Caco-2 cell monolayers confirmed that the IPMs were endocytosed in their intact forms through macropinocytosis, clathrin-, and caveolae-mediated pathways. In conclusion, the results suggested that the mixed micelles of Soluplus® and Poloxamer 407 could be a feasible drug delivery system to enhance oral bioavailability of icaritin, and the ABS method might be a promising technology for the preparation of polymeric micelles to encapsulate poorly water-soluble weakly acidic and alkaline drugs. 相似文献
992.
Wenxuan Jiang Wei Wei Tinglian Yuan Shasha Liu Ben Niu Hui Wang Wei Wang 《Chemical science》2021,12(24):8556
The inevitable microstructural defects, including cracks, grain boundaries and cavities, make a portion of the material inaccessible to electrons and ions, becoming the incentives for electrochemically inactive zones in single entity. Herein, we introduced dark field microscopy to study the variation of scattering spectrum and optical mass centroid (OMC) of single Prussian blue nanoparticles during electrochemical reaction. The “dark zone” embedded in a single electroactive nanoparticle resulted in the incomplete reaction, and consequently led to the misalignment of OMC for different electrochemical intermediate states. We further revealed the dark zones such as lattice defects in the same entity, which were externally manifested as the fixed pathway for OMC for the migration of potassium ions. This method opens up enormous potentiality to optically access the heterogeneous intraparticle dark zones, with implications for evaluating the crystallinity and electrochemical recyclability of single electroactive nano-objects.The schematic of single cubic-shaped Prussian blue (PB) mesocrystals formed by the oriented aggregation of small nanocrystals. The dark-field images of single PB nanoparticle at PB and Prussian white (PW) states, respectively. 相似文献
993.
A quantitative analysis method for penicillins including ampicillin (AmP), benzyl penicillin (BP), oxacillin (OA) and amoxycillin (AmO) is proposed that makes use of the totally internally reflected resonance light scattering (TIR-RLS) signal from the penicillin at the H2O/CCl4 interface in the presence of cetyltrimethylammonium bromide (CTMAB), and enables the pharmacokinetics of penicillin taken orally and excreted through urine to be monitored. Penicillin is coadsorbed with CTMAB at the H2O/CCl4 interface in neutral solution, resulting in the formation of ion associates that display greatly enhanced TIR-RLS signals (maximum at 368–372 nm). This enhanced TIR-RLS intensity was found to be proportional to the penicillin concentration over the range 0.2×10–6 to 2.2×10–6 mol L–1, with limits of determination (3) of 5.0×10–8 to 7.0×10–8 mol L–1. Pharmacokinetics studies performed using the present method show that the excretion of orally-taken ampicillin through urine has a half-time of 1.05 h and an excremental quantum over 8 h of 49.3%, respectively. 相似文献
994.
Jing Juan XU Gang WANG Qing ZHANG Xing Hua XIA Hong Yuan CHEN? The Laboratory of Life Analytical Chemistry Department of Chemistry Nanjing University Nanjing 《中国化学快报》2005,16(4)
Carbon nanotube (CNT) is a novel carbon material discovered by Iijima1. It had beenfound to have the ability to promote electron transfer reactions when it was used tofabricate electrodes for the oxidation of biomolecules2-4. Just recently, the interest indemonstrating CNT for biosensing applications is now emerging5-10. However, most ofthese biosensors were based on CNT paste electrode or CNT modified glassy carbonelectrode by casting technology. Here, we reported another assembly… 相似文献
995.
Synthesis and Characterization of Dual Acidic Ionic Liquids 总被引:1,自引:0,他引:1
Xiao Hua WANG Guo Hong TAO Zi Yan ZHANG Yuan KOU 《中国化学快报》2005,16(12):1563-1565
Novel ionic liquids with dual acidity, of which the cation contains Brφnsted acidity and anions contain Lewis acidity were synthesized. These ionic liquids obtained were identified by NMR, FF-IR, SDT and FAB-MS. Their acidities were determined by pyridine probe on IR spectrography. 相似文献
996.
考虑到手性毛细管电泳分离机理的复杂性,提出了不依赖于统计模型的二进制编码遗传算法多目标优化策略。根据实验参数的多少及其重要性,采用均匀设计安排完成初步实验。并用Derringer功效函数作为多指标同时优化的评价指标,以取得较高的分离度和较快分离速度;通过对实验参数给予编码,转化为二进制字符串,根据得到的总功效函数值大小进行遗传算法操作,产生新的一组实验条件。重复上述过程直到得到最佳分离条件为止。此方法成功地应用于华法令对映体的毛细管电泳分离条件优化。 相似文献
997.
A new ligand H2L, 1,7-di(1-phenyl-3-methyl-5-pyrazolone-4-benzylidene)diethenetriamine and its three transition metal complexes, ML · nH2O [M=Cu(II), n=2; M=Zn(II), n=0.5; M=Ni(II) (1), n=3] have been synthesized in anhydrous EtOH and characterized on the basis of elemental analyses, molar conductivities, i.r.
spectra, u.v. spectra and thermal analyses. In addition, the DNA-binding properties of the ligand and its complexes have been
investigated by absorption, fluorescence and viscosity measurements. The experimental results indicated that the ligand and
the complex (1) can bind to DNA , but the other two complexes can’t; the binding affinity of the complex (1) is higher than
that of the ligand and the intrinsic binding constant kb of the complex (1) is 7.893×105 m−1. 相似文献
998.
Jiang Ke QIN Xian Zhang BU Yu Fang WANG Zhi Yun DU Xing Yuan WANG Zhi Shu HUANG Lin MA Lin Kun AN Lian Quan GU 《中国化学快报》2005,16(11):1451-1454
The reactions of tanshinone IIA with aromatic aldehydes have been investigated and several 2, T-(substituted arylmethylene) bis (1,6,6-trimethyl-6,7,8,9-tetrahydrophenanthro[1,2-b]- furan- 10, 11-dione) derivatives were obtained, 相似文献
999.
Jinyun Zheng Yujian Yu Xiaomin Zhen Erbing Yang Yufen Zhao 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):1564-1575
Abstract A series of new nitrogen heterocyclic compounds containing sulfur–ether (8a–8f) and Schiff-base (9a–9q) functionalities were synthesized by the reaction of the pharmaceutical lead compound containing both benzimidazole and 1,2,4-triazole rings. The compounds were characterized by 1H NMR, 13C NMR, FT-IR, HR-MS, and ESI-MS. 相似文献
1000.
Atom transfer radical polymerization (ATRP) of MMA was conducted using 2‐(4‐chloromethyl‐phenyl)‐benzoxazole as initiator, CuCl as catalyst, and PMDETA as ligand. The results show that the polymerization is a first order reaction with respect to monomer concentration. The polymerization displayed living character as evidenced by a liner increase of monomer weight with conversation and a relatively narrow distribution (Mn/Mw range from 1.30 to 1.45). The structure of PMMA was analyzed by 1H‐NMR and proved the polymerization could be controlled to some degree. The optical property of the initiator was well preserved in the resulting PMMA, and the end‐functionalized PMMA exhibited fluorescent emission at 360 nm whether in DMF solution or in film state. 相似文献