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991.
A novel drug-loaded pathogen-mimicking nanocomplex (MSN-DOX-SP-LPS) has been constructed for synergistic chemo-immunotherapy. 相似文献
992.
Jiasi Wang Peng Shi Kai Dong Zhengqing Yan Jinsong Ren Xiaogang Qu 《Materials Today》2017,20(8):406-412
Here we develop a strategy using near infrared (NIR) modulation of telomerase activity based on gold nanocage@smart polymer system. Using this biocompatible design, we can regulate cellular behavior. This system has been used in vivo by taking advantages of NIR. This is the first example for optical modulation of telomerase activity in living cells and tissues. 相似文献
993.
Ying Chen Yan-qing Dong Zhe Yan Dong Chen Yong Chen Lu-hui Wang 《Fullerenes, Nanotubes and Carbon Nanostructures》2017,25(6):363-370
Carbonization of magnetic polymer microspheres is one of the methods for the preparation of magnetic carbon materials. Fe3O4 magnetic particle characteristics considerably influence the magnetic content and size distribution of magnetic polymer microspheres. The characteristics of Fe3O4 nanoparticles modified by oleic acid (OA) and undecylenic acid (UA) were analyzed by X-ray diffraction, Fourier transform infrared, scanning electron microscopy, dynamic laser light scattering, thermogravimetry/differential thermogravimetry, vibrating sample magnetometer, and water contact angle. Fe3O4 nanoparticles modified by OA and UA are nearly spherical and exhibit superparamagnetism. Fe3O4 particle size and saturation magnetization are slightly influenced by the OA and UA composition. OA and UA both are chemically adsorbed onto Fe3O4 as bidentate chelates. OA shows easier adsorption onto Fe3O4 than UA. OA groups have an expanded arrangement on OA@Fe3O4, whereas UA groups have a condensed arrangement on UA@Fe3O4. Particle lipophilicity decreases and particle clustering increases with decreasing OA content and increasing UA content on OA-UA@Fe3O4 nanoparticles. 相似文献
994.
Chao‐Yu Li Zhen‐Wei Yang Jin‐Chao Dong Tapan Ganguly Jian‐Feng Li 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(8)
Shell‐isolated nanoparticle‐enhanced Raman spectroscopy (SHINERS), due to its versatility, has been able to break the long‐term limitations of the material‐ and substrate‐specific generalities in the traditional field of surface‐enhanced Raman spectroscopy. With a shell‐isolated work principle, this method provides an opportunity to investigate successfully in surface, biological systems, energetic materials, and environmental sciences. Both the shell material and core morphology are being improved continuously to meet the requirements in diverse systems, such as the electrochemical studies at single crystal electrode surfaces, in situ monitoring of photoinduced reaction processes, practical applications in energy conversion and storage, inspections in food safety, and the surface‐enhanced fluorescence. Predictably, the concept of shell‐isolated nanoparticle‐enhancement could be expanded to the wider range for the performance of plasmon‐enhanced spectral modifications. 相似文献
995.
Drug‐Loaded Mesoporous Tantalum Oxide Nanoparticles for Enhanced Synergetic Chemoradiotherapy with Reduced Systemic Toxicity 下载免费PDF全文
Yuyan Chen Guosheng Song Ziliang Dong Xuan Yi Yu Chao Chao Liang Kai Yang Liang Cheng Zhuang Liu 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(8)
Combining chemotherapy and radiotherapy (chemoradiotherapy) has been widely applied in many clinical practices, showing promises in enhancing therapeutic outcomes. Nontoxic nanocarriers that not only are able to deliver chemotherapeutics into tumors, but could also act as radiosensitizers to enhance radiotherapy would thus be of great interest in the development of chemoradiotherapies. To achieve this aim, herein mesoporous tantalum oxide (mTa2O5) nanoparticles with polyethylene glycol (PEG) modification are fabricated. Those mTa2O5‐PEG nanoparticles could serve as a drug delivery vehicle to allow efficient loading of chemotherapeutics such as doxorubicin (DOX), whose release appears to be pH responsive. Meanwhile, owing to the interaction of Ta with X‐ray, mTa2O5‐PEG nanoparticles could offer an intrinsic radiosensitization effect to increase X‐ray‐induced DNA damages during radiotherapy. As a result, DOX‐loaded mTa2O5‐PEG (mTa2O5‐PEG/DOX) nanoparticles can offer a strong synergistic therapeutic effect during the combined chemoradiotherapy. Furthermore, in chemoradiotherapy, such mTa2O5‐PEG/DOX shows remarkably reduced side effects compared to free DOX, which at the same dose appears to be lethal to animals. This work thus presents a new type of mesoporous nanocarrier particularly useful for the delivery of safe and effective chemoradiotherapy. 相似文献
996.
Zhi Zhou Li Feng Liang Ming Peng Zhuo Ying Li Shi Xue Dong Wang Liang Sheng Liao 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(19)
Organic semiconductor micro‐/nanocrystals with regular shapes have been demonstrated for many applications, such as organic field‐effect transistors, organic waveguide devices, organic solid‐state lasers, and therefore are inherently ideal building blocks for the key circuits in the next generation of miniaturized optoelectronics. In the study, blue‐emissive organic molecules of 1,4‐bis(2‐methylstyryl)benzene (o‐MSB) can assemble into rectangular microcrystals at a large scale via the room‐temperature solution‐exchange method. Because of the Förster resonance energy transfer, the energy of the absorbed photons by the host matrix organic molecules of o‐MSB can directly transfer to the dopant organic molecules of tetracene or 1,2:8,9‐dibenzopentacene (DBP), which then emit visible photons in different colors from blue to green, and to yellow. More impressively, by modulating the doping molar ratios of DBP to o‐MSB, bright white‐emissive organic microcrystals with well‐preserved rectangular morphology can be successfully achieved with a low doping ratio of 1.5%. These self‐assembled organic semiconductor microcrystals with multicolor emissions can be the white‐light sources for the integrated optical circuits at micro‐/nanoscale. 相似文献
997.
Flexible Nonvolatile Transistor Memory with Solution‐Processed Transition Metal Dichalcogenides 下载免费PDF全文
Richard Hahnkee Kim Jinseong Lee Kang Lib Kim Suk Man Cho Dong Ha Kim Cheolmin Park 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(20)
Nonvolatile field‐effect transistor (FET) memories containing transition metal dichalcogenide (TMD) nanosheets have been recently developed with great interest by utilizing some of the intriguing photoelectronic properties of TMDs. The TMD nanosheets are, however, employed as semiconducting channels in most of the memories, and only a few works address their function as floating gates. Here, a floating‐gate organic‐FET memory with an all‐in‐one floating‐gate/tunneling layer of the solution‐processed TMD nanosheets is demonstrated. Molybdenum disulfide (MoS2) is efficiently liquid‐exfoliated by amine‐terminated polystyrene with a controlled amount of MoS2 nanosheets in an all‐in‐one floating‐gate/tunneling layer, allowing for systematic investigation of concentration‐dependent charge‐trapping and detrapping properties of MoS2 nanosheets. At an optimized condition, the nonvolatile memory exhibits memory performances with an ON/OFF ratio greater than 104, a program/erase endurance cycle over 400 times, and data retention longer than 7 × 103 s. All‐in‐one floating‐gate/tunneling layers containing molybdenum diselenide and tungsten disulfide are also developed. Furthermore, a mechanically‐flexible TMD memory on a plastic substrate shows a performance comparable with that on a hard substrate, and the memory properties are rarely altered after outer‐bending events over 500 times at the bending radius of 4.0 mm. 相似文献
998.
999.
1000.
Broadband Light Absorption and Efficient Charge Separation Using a Light Scattering Layer with Mixed Cavities for High‐Performance Perovskite Photovoltaic Cells with Stability 下载免费PDF全文
Byeong Cheul Moon Jung Hyo Park Dong Ki Lee Nikolai Tsvetkov Ilwoo Ock Kyung Min Choi Jeung Ku Kang 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(30)
CH3NH3PbI3 is one of the promising light sensitizers for perovskite photovoltaic cells, but a thick layer is required to enhance light absorption in the long‐wavelength regime ranging from PbI2 absorption edge (500 nm) to its optical band‐gap edge (780 nm) in visible light. Meanwhile, the thick perovskite layer suppresses visible‐light absorption in the short wavelengths below 500 nm and charge extraction capability of electron–hole pairs produced upon light absorption. Herein, we find that a new light scattering layer with the mixed cavities of sizes in 100 and 200 nm between transparent fluorine‐doped tin oxide and mesoporous titanium dioxide electron transport layer enables full absorption of short‐wavelength photons (λ < 500 nm) to the perovskite along with enhanced absorption of long‐wavelength photons (500 nm < λ < 780 nm). Moreover, the light‐driven electric field is proven to allow efficient charge extraction upon light absorption, thereby leading to the increased photocurrent density as well as the fill factor prompted by the slow recombination rate. Additionally, the photocurrent density of the cell with a light scattering layer of mixed cavities is stabilized due to suppressed charge accumulation. Consequently, this work provides a new route to realize broadband light harvesting of visible light for high‐performance perovskite photovoltaic cells. 相似文献