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91.
Yolk‐Shell Porous Microspheres of Calcium Phosphate Prepared by Using Calcium L‐Lactate and Adenosine 5′‐Triphosphate Disodium Salt: Application in Protein/Drug Delivery 下载免费PDF全文
Guan‐Jun Ding Prof. Dr. Ying‐Jie Zhu Chao Qi Tuan‐Wei Sun Dr. Jin Wu Dr. Feng Chen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(27):9868-9876
A facile and environmentally friendly approach has been developed to prepare yolk‐shell porous microspheres of calcium phosphate by using calcium L ‐lactate pentahydrate (CL) as the calcium source and adenosine 5′‐triphosphate disodium salt (ATP) as the phosphate source through the microwave‐assisted hydrothermal method. The effects of the concentration of CL, the microwave hydrothermal temperature, and the time on the morphology and crystal phase of the product are investigated. The possible formation mechanism of yolk‐shell porous microspheres of calcium phosphate is proposed. Hemoglobin from bovine red cells (Hb) and ibuprofen (IBU) are used to explore the application potential of yolk‐shell porous microspheres of calcium phosphate in protein/drug loading and delivery. The experimental results indicate that the as‐prepared yolk‐shell porous microspheres of calcium phosphate have relatively high protein/drug loading capacity, sustained protein/drug release, favorable pH‐responsive release behavior, and a high biocompatibility in the cytotoxicity test. Therefore, the yolk‐shell porous microspheres of calcium phosphate have promising applications in various biomedical fields such as protein/drug delivery. 相似文献
92.
93.
Xi‐Sha Zhang Yun‐Fei Zhang Zhao‐Wei Li Fei‐Xian Luo Zhang‐Jie Shi 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2015,127(18):5568-5572
A rhodium(III)‐catalyzed cross‐coupling of benzyl thioethers and aryl carboxylic acids through the two directing groups is reported. Useful structures with diverse substituents were efficiently synthesized in one step with the cleavage of four bonds (C H, C S, O H) and the formation of two bonds (C C, C O). The formed structure is the privileged core in natural products and bioactive molecules. This work highlights the power of using two different directing groups to enhance the selectivity of a double C H activation, the first of such examples in cross‐oxidative coupling. 相似文献
94.
Rational Design of an Ultrasensitive and Highly Selective Chemodosimeter by a Dual Quenching Mechanism for Cysteine Based on a Facile Michael‐Transcyclization Cascade Reaction 下载免费PDF全文
Xiangmin Li Yongjun Zheng Hongjuan Tong Rui Qian Dr. Lin Zhou Prof. Dr. Guixia Liu Prof. Dr. Yun Tang Prof. Dr. Hao Li Prof. Dr. Kaiyan Lou Prof. Dr. Wei Wang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(27):9247-9256
Differentiation of biologically important thiols, such as cysteine (Cys), homocysteine (Hcy), and glutathione (GSH) is still a challenging task. Herein, we present a novel fluorescent chemodosimeter capable of selectively detecting Cys over other biothiols including Hcy and GSH and other amino acids by a facile thiol‐Michael addition/transcyclization rearrangement cascade click process. The unique transcyclization step is critical for the selectivity as a result of the kinetically favorable formation of a six‐membered ring with the Cys Michael adduct. Moreover, the probe adopts a distinctive dual quenching mechanism—photoinduced electron transfer (PET) and photoinduced intramolecular charge transfer (ICT) to deliver a drastic turn‐on fluorescence response only at the Cys‐selective transcylization step. The judicious selection of strong electron‐withdrawing naphthalimide fluorophore with maleimide group enhances the electrophilicity and thus reactivity for the cascade process leading to fast detection and ultrasensitivity with a detection limit of 2.0 nm (S/N=3). The probe has demonstrated its practical utility potential in Cys imaging in live cells. 相似文献
95.
Visible‐Light‐Induced Trifluoromethylation of Isonitrile‐Substituted Methylenecyclopropanes: Facile Access to 6‐(Trifluoromethyl)‐7,8‐Dihydrobenzo[k]phenanthridine Derivatives 下载免费PDF全文
Yu‐Chao Yuan Hou‐Lu Liu Xu‐Bo Hu Prof. Dr. Yin Wei Prof. Dr. Min Shi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(37):13059-13063
A new visible‐light‐induced trifluoromethylation of isonitrile‐substituted methylenecyclopropanes is developed. A range of substituted 6‐(trifluoromethyl)‐7,8‐dihydrobenzo[k]phenanthridine derivatives are readily furnished by this newly developed tandem reaction with moderate to good yields. This reaction allows the direct formation of two six‐membered rings and three new C?C bonds, including the C?CF3 bond, under visible light irradiation. 相似文献
96.
Cover Picture: One‐Step Synthesis of Silver Nanoparticle‐Decorated Hydroxyapatite Nanowires for the Construction of Highly Flexible Free‐Standing Paper with High Antibacterial Activity (Chem. Eur. J. 32/2016) 下载免费PDF全文
97.
The nonisothermal decomposition kinetics of Ginkgo biloba leaves polyprenol (GBP) and cleaved situation of its chemical bond during thermal decomposition process were first investigated using thermogravimetric (TG) and TG‐FTIR technology. The results of thermal decomposition kinetics revealed that the nonisothermal decomposition mechanism of GBP corresponds to first‐order chemical reaction with n = 1, integral form g(a) = –ln(1 – a) and differential form f(a) = 1 – a. TG‐FTIR results demonstrated that absorbance of –CH3, unsaturated C–H bond, =CH2, accumulated C=C, –OH, and so on constantly increased with thermal decomposition reaction went on. In addition, storage life of GBP was also evaluated. These data could provide theoretical guidance for purification under high temperature and other thermal application of GBP. 相似文献
98.
Extraordinary transport behavior of gases in isothermally annealed poly(4‐methyl‐1‐pentene) membranes 下载免费PDF全文
Ywu‐Jang Fu Cheng‐Lee Lai Chien‐Chieh Hu Yi‐Ming Sun Shuan‐Ying Wu Jung‐Tsai Chen Shu‐Hsien Huang Wei‐Song Hung Kueir‐Rarn Lee 《Journal of Polymer Science.Polymer Physics》2016,54(22):2368-2376
Poly(4‐methyl‐1‐pentene) (PMP) membranes were modified through isothermal annealing to investigate the change of their crystalline structure and rigid and mobile amorphous fractions (RAF and MAF), assuming a three‐phase model, affected the gas transport behavior. The crystalline structure was characterized by wide‐angle X‐ray diffraction (WAXD) and small‐angle X‐ray scattering (SAXS) techniques, and the free volume properties were analyzed by positron annihilation lifetime spectroscopy. Compared with the pristine membrane, the annealed membranes show higher crystallinity; the crystals undergo partial structural change from form III to form I. The lamellar crystal thickness, rigid amorphous fraction thickness, and long period in the lamellar stacks increase with crystallinity. The annealed PMP membranes exhibit higher permeability due to the increase in larger size free volumes in MAF and higher selectivity due to the increase in smaller size free volumes in RAF, respectively. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016 , 54, 2368–2376 相似文献
99.
100.
Temperature‐dependent phase‐segregation behavior and antifouling performance of UV‐curable methacrylated PDMS/PEG coatings 下载免费PDF全文
Yunjiao Gu Shuxue Zhou Huali Luo Limin Wu Wei Gao Jinlong Yang 《Journal of Polymer Science.Polymer Physics》2016,54(16):1612-1623
Controllable phase segregation adjustment for immiscible polymer blends has always been tough, which hinders the development of amphiphilic antifouling coatings from more accessible blends. Herein, methacrylated poly(dimethylsiloxane) (PDMS‐MA) was synthesized and mixed with poly(ethylene glycol)methylether methacrylate (PEG‐MA). It was interestingly discovered that these PDMS‐MA/PEG‐MA blends displayed upper critical solution temperatures (UCST) due to thermo‐induced conformational change of PEG‐MA and the UCST changed with PDMS‐MA/PEG‐MA mass ratios. Micro‐/nano‐phase segregation, nanophase segregation, or homogenous morphology were therefore achieved. These PDMS‐MA/PEG‐MA blends with different mass ratios were UV‐cured under varying temperatures to fabricate coatings. Their surface morphology and wettability are readily adjusted by phase segregation. For the first time, highly hydrophilic surface was achieved for coatings with microphase segregation because of the exposure of PEG‐rich domains, which exhibited an enhanced protein resistance against bovine serum albumin (BSA). Anti‐bacterial performance (Shewanella loihica) was also observed for these PDMS/PEG coatings. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016 , 54, 1612–1623 相似文献