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41.
Yu Zhao Jiaying Yang Danli Hao Ran Xie Lingyu Jia Miyi Yang Hai Ma Pengqian Wang Weipeng Yang Feng Sui Haiyu Zhao Yanjun Chen Qinghe Zhao 《Macromolecular bioscience》2023,23(2):2200430
Methicillin-resistant Staphylococcus aureus (MRSA) can induce multiple inflammations. The biofilm formed by MRSA is resistant to a variety of antibiotics and is extremely difficult to cure, which seriously threatens human health. Herein, a nanoparticle encapsulating berberine with polypyrrole core and pH-sensitive shell to provide chemo-photothermal dual therapy for MRSA infection is reported. By integrating photothermal agent polypyrrole, berberine, acid-degradable crosslinker, and acid-induced charge reversal polymer, the nanoparticle exhibited highly efficient MRSA infection treatment. In normal uninfected areas and bloodstream, nanoparticles showed negatively charged, demonstrating high biocompatibility and excellent hemocompatibility. However, once arriving at the MRSA infection site, the nanoparticle can penetrate and accumulate in the biofilm within 2 h. Simultaneously, berberine can be released into biofilm rapidly. Under the combined effect of photothermal response and berberine inhibition, 88.7% of the biofilm is removed at 1000 µg mL−1. Moreover, the nanoparticles have an excellent inhibitory effect on biofilm formation, the biofilm inhibition capacity can reach up to 90.3%. Taken together, this pH-tunable nanoparticle can be employed as a new generation treatment strategy to fight against the fast-growing MRSA infection. 相似文献
42.
Xiaona Rong Nabila Mehwish Xueming Niu Niteng Zhu Bae Hoon Lee 《Macromolecular bioscience》2023,23(3):2200463
Nowadays, hydrogels-based microneedles (MNs) have attracted a great interest owing to their outstanding qualities for biomedical applications. For the fabrication of hydrogels-based microneedles as tissue engineering scaffolds and drug delivery carriers, various biomaterials have been tested. They are required to feature tunable physiochemical properties, biodegradability, biocompatibility, nonimmunogenicity, high drug loading capacity, and sustained drug release. Among biomaterials, human proteins are the most ideal biomaterials for fabrication of hydrogels-based MNs; however, they are mechanically weak and poorly processible. To the best of the knowledge, there are no reports of xeno-free human protein-based MNs so far. Here, human albumin-based hydrogels and microneedles for tissue engineering and drug delivery by using relatively new processible human serum albumin methacryloyl (HSAMA) are engineered. The resultant HSAMA hydrogels display tunable mechanical properties, biodegradability, and good biocompatibility. Moreover, the xeno-free HSAMA microneedles display a sustained drug release profile and significant mechanical strength to penetrate the model skin. In vitro, they also show good biocompatibility and anticancer efficacy. Sustainable processible human albumin-based biomaterials may be employed as a xeno-free platform in vivo for tissue engineering and drug delivery in clinical trials in the future. 相似文献
43.
Rui Tao Xue-Jiao Yin Ke-Hu Wang Yu-Zhuo Niu Ya-Lin Wang Dan-Feng Huang Ying-Peng Su Jin-Xian Wang Yu-Lai Hu Ying Fu Zheng-Yin Du 《中国化学快报》2015,26(8):1046-1049
Exceedingly fast preparation of trifluoromethyl tertiary alcohols has been accomplished from methyl ketones and trifluoromethyl ketones under solvent free conditions by cross Aldol reaction. The reaction was achieved in the presence of common inorganic base by grinding method at ambient temperature to give β-trifluoromethyl-β-hydroxyl ketones in high yields (up to 95%). 相似文献
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Cai-Li Sun Jiang-Fei Xu Yu-Zhe Chen Li-Ya Niu Li-Zhu Wua Chen-Ho Tung Qing-Zheng Yang 《中国化学快报》2015,26(7):843-846
A new monofunctionalized pillar[5]arene bearing imidazolium moiety that formed stable [1]pseudorotaxane even at high concentration (100 mmol/L) was reported. [1]Rotaxane was obtained effi ciently through thiol-ene reaction from [1]pseudorotaxane which further confi rmed the formation of [1]pseudorotaxane. 相似文献
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以氯化1-丁基-3-甲基咪唑鎓([Bmim]Cl)和二元羧酸为原料,由不同摩尔比混合制备了一类新型低共熔溶剂,采用红外光谱对[Bmim]Cl和二元羧酸之间的作用进行了分析。分别测定了其粘度、电导率、密度、折射率等物理性质,并研究了温度、二元羧酸结构和摩尔比对这些物理性质的影响。结果表明,新型低共熔溶剂的粘度随温度的升高而降低,电导率随温度的升高而增加。温度对两者的影响可以采用VTF方程进行精确地拟合。新型低共熔溶剂的密度随温度的升高而呈线性下降。对新型低共熔溶剂的过量摩尔体积进行计算的结果表明,过量摩尔体积均为正值,二元羧酸对过量摩尔体积的贡献远大于[BMIM]Cl,而结构特性的贡献多于物理作用。折射率和密度随二元羧酸碳数的变化趋势基本相似。 相似文献
46.
Dr. Dongdi Zhang Fan Cao Pengtao Ma Chao Zhang Prof. Dr. You Song Zhijie Liang Xiaojing Hu Prof. Jingping Wang Prof. Dr. Jingyang Niu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(49):17683-17690
By deliberately using a metastable polyanion [(NbO2)6P2W12O56]12? ( 1 ), which was formed in situ, we have discovered the unprecedented hexameric cluster {Mn15(Nb6P2W12O62)6} ( 2 ), in which the six polyanions [Nb6P2W12O61]10? are alternately connected by four intriguing trinuclear {MnIII3} moieties and four {MnII} linkers. This discovery is the first in which the phosphoniobotungstate has been made accessible by using transition‐metal ions; furthermore, polyanion 2 represents the largest niobotungstate cluster reported to date. Analysis by means of electrospray ionization mass spectrometry (ESI‐MS ) provides insight into the self‐assembly process, and the peaks observed relate to the different charge states of the parent cluster, thus confirming the stability of 2 . In addition, magnetic‐susceptibility measurements reveal that each {MnIII3} subunit is a separate single‐molecule magnet (SMM). This discovery results from the exploration of the reverse effect of metastable polyanion 1 possessing high reactivity, thereby turning a disadvantage into an advantage. This finding could define a new synthetic strategy for the design and synthesis of magnetic polyoxometalate (POM) clusters. 相似文献
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48.
Photo‐responsive amphiphilic poly(α‐hydroxy acids) with pendent o‐nitrobenzyl ester constructed via copper‐catalyzed azide‐alkyne cycloaddition reaction 下载免费PDF全文
Xiangyu Liu Jingwen He Yile Niu Yefei Li Ding Hu Xinnian Xia Yanbing Lu Weijian Xu 《先进技术聚合物》2015,26(5):449-456
Photo‐responsive block copolymer mPEG‐b‐poly(Tyr)‐g‐NB was prepared by introduction of o‐nitrobenzyl ester group into the side chain of amphiphilic poly(ethylene glycol)‐b‐poly(α‐hydroxy acids) (mPEG‐b‐poly(Tyr)) containing pendent alkynyl group via copper‐catalyzed azide‐alkyne cycloaddition reaction. The amphiphilic mPEG‐b‐poly(Tyr) was synthesized via the ring‐opening polymerization of O‐carboxyanhydrides, with monomethoxy poly(ethylene glycol) (mPEG) as macroinitiator. The molecular structure, self‐assembly, and photo‐controlled release of the obtained mPEG‐b‐poly(Tyr)‐g‐NB were thoroughly investigated. mPEG‐b‐poly(Tyr)‐g‐NB could self‐assemble into spherical micelles in water and showed disassembly under UV light irradiation, which was demonstrated by means of UV‐vis spectroscopy, scan electron microscopes, and dynamic light scattering measurement. Fluorescence emission measurements demonstrated that Nile red, encapsulated by micelles, can be released upon UV irradiation. This study provides a convenient way to construct smart poly(α‐hydroxy acids)‐based nanocarriers for controlled release of hydrophobic drugs. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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