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Muhammad Ali Dominik H. Hasenhrl Lukas Zeininger Alexander R. M. Müllner Herwig Peterlik Andreas Hirsch 《Helvetica chimica acta》2019,102(4)
A new prototype of reversible self‐assembly between functionalized gold and titanium dioxide nanoparticles (NPs) utilizing hydrogen bonding interactions was developed and established. The gold nanoparticles were functionalized with a Hamilton‐receptor functionality bearing a thiol moiety as anchoring group. The titanium dioxide nanoparticles were modified with cyanurate derivatives which contained phosphonic acids as anchoring groups. The host–guest type interaction between two functionalized nanoparticles yielded a highly integrated nanoparticle system in chloroform. Moreover, by presenting a competing ligand in an exchange reaction, the product of self‐assembly can be segregated into the individual soluble components of functionalized nanoparticles. The self‐assembly and the exchange reaction were followed and monitored in detail by UV/Vis spectroscopy. The structure of the self‐assembly product was investigated using scanning electron microscopy (SEM) and small‐angle X‐ray scattering (SAXS). 相似文献
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In this paper, a new type of quaternionic partner curves is defined as generalized quaternionic involute-evolute curves or -quaternionic involute– -quaternionic evolute curves in the four-dimensional Euclidean space. The relations between the Frenet frames and curvatures of the quaternionic involute-evolute curve couple are introduced. Moreover, the necessary and sufficient conditions for a quaternionic curve to have a generalized involute are obtained. 相似文献
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Ali Maruf Yi Wang Li Luo Yuan Zhong Deti Nurhidayah Boyan Liu Dan Tang Muhammad Abdul Rouf Haijun Zhang Yuxia Yin Wei Wu Guixue Wang 《Particle & Particle Systems Characterization》2020,37(5):2000021
The development of smart nanoagents that can respond to a specific stimulus has gained remarkable interest for treating various kinds of diseases, including atherosclerosis. On the other hand, a cell camouflaging strategy has been considered as a pivotal factor to improve the delivery stealthiness, biocompatibility, and biodegradability of nanocarriers, resolving the shortcomings of PEGylation. In this study, reactive oxygen species (ROS)-responsive 5-aminolevulinic acid (ALA) prodrug nanostructures (ROSELLA) encapsulating rapamycin (RAP) are blended with nanoerythrocyte membranes to construct red blood cell membrane (RBCM)/RAP@ROSELLA. These nanoagents are designed to be able to escape the biological barriers, accumulate in atherosclerosis lesions, and enhance the release of drugs in the intracellular milieu due to the magnification of hydrogen peroxide (H2O2). In vitro study proves its superior ability to inhibit the proliferation of macrophages and vascular smooth muscle cells. In vivo developmental toxicity further confirms that no significant systematic toxicity is induced by RBCM/RAP@ROSELLA, implying its favorable biocompatibility, which has potential for precise nanomedicine to combat atherosclerosis. 相似文献
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Muhammad Faisal Danish Shahzad Aamer Saeed Bhajan Lal Shomaila Saeed Fayaz Ali Larik Pervaiz Ali Channar Parvez Ali Mahesar Jamaluddin Mahar 《Tetrahedron: Asymmetry》2017,28(11):1445-1461
Isoquinuclidines constitute the central structural nucleus of numerous biologically active natural products, for example, iboga alkaloids such as ibogamine and catharanthine as well as non-indole-containing alkaloids such as the dioscorine and the cannivonines. Furthermore, in medicinal and pharmaceutical chemistry, the isoquinuclidine core is commonly employed as a rigid azabicyclic scaffold, thus providing significant precursors in the synthesis of numerous valuable alkaloids. Summarizing well-organized approaches to access the chiral isoquinuclidine structural centerpiece signifies a significant endeavor not only for developing biologically active natural products but also enhancing biological researches that can lead to possible drug discovery. Over time, the values and methodologies for the asymmetric synthesis of chiral isoquinuclidines are increasing; hence to advance asymmetric synthesis, this review combines and discusses the pros and cons of each synthesis techniques from 2008. This review should be helpful for promoting further developments of asymmetric synthetic methodologies and for medicinal chemistry. 相似文献
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Muhammad Danish Rabia Ayub Butt Saba Akbar Muhammad Ashfaq Graham Smith 《Journal of chemical crystallography》2016,46(10-12):421-428