Design of a Universal Reversible Bidirectional Current Switch Based on the Fullerene–Phthalocyanine Supramolecular System

2012 ◽  
Vol 116 (25) ◽  
pp. 6785-6791 ◽  
Author(s):  
Dongdong Qi ◽  
Lijuan Zhang ◽  
Liang Wan ◽  
Luyang Zhao ◽  
Jianzhuang Jiang
Keyword(s):  
Supramolecular System ◽  
Current Switch

scholarly journals Solvent-Controlled Self-Assembled Oligopyrrolic Receptor

Molecules ◽  
2021 ◽  
Vol 26 (6) ◽  
pp. 1771
Author(s):  
Fei Wang ◽  
Kejiang Liang ◽  
Mads Christian Larsen ◽  
Steffen Bähring ◽  
Masatoshi Ishida ◽  
...  
Keyword(s):  
Materials Science ◽  
Science Research ◽  
Polymeric Chain ◽  
Supramolecular System ◽  
Receptor System ◽  
One Dimensional ◽  
X Ray ◽  
Host Guest Complex ◽  
Colorimetric Response ◽  
Strong Acids

We report a fully organic pyridine-tetrapyrrolic U-shaped acyclic receptor 10, which prefers a supramolecular pseudo-macrocyclic dimeric structure (10)2 in a less polar, non-coordinating solvent (e.g., CHCl3). Conversely, when it is crystalized from a polar, coordinating solvent (e.g., N,N-dimethylformamide, DMF), it exhibited an infinite supramolecular one-dimensional (1D) “zig-zag” polymeric chain, as inferred from the single-crystal X-ray structures. This supramolecular system acts as a potential receptor for strong acids, e.g., p-toluenesulfonic acid (PTSA), methane sulfonic acid (MSA), H2SO4, HNO3, and HCl, with a prominent colorimetric response from pale yellow to deep red. The receptor can easily be recovered from the organic solution of the host–guest complex by simple aqueous washing. It was observed that relatively stronger acids with pKa < −1.92 in water were able to interact with the receptor, as inferred from 1H NMR titration in tetrahydrofuran-d8 (THF-d8) and ultraviolet–visible (UV–vis) spectroscopic titrations in anhydrous THF at 298 K. Therefore, this new dynamic supramolecular receptor system may have potentiality in materials science research.

scholarly journals Photo-Responsive Supramolecular Micelles for Controlled Drug Release and Improved Chemotherapy

2020 ◽  
Vol 22 (1) ◽  
pp. 154
Author(s):  
Fasih Bintang Ilhami ◽  
Kai-Chen Peng ◽  
Yi-Shiuan Chang ◽  
Yihalem Abebe Alemayehu ◽  
Hsieh-Chih Tsai ◽  
...  
Keyword(s):  
Reactive Oxygen Species ◽  
Drug Release ◽  
Visible Light ◽  
Cancer Cells ◽  
Laser Irradiation ◽  
Reactive Oxygen ◽  
Controlled Drug Release ◽  
Grand Challenge ◽  
Supramolecular System ◽  
Oxygen Species

Development of stimuli-responsive supramolecular micelles that enable high levels of well-controlled drug release in cancer cells remains a grand challenge. Here, we encapsulated the antitumor drug doxorubicin (DOX) and pro-photosensitizer 5-aminolevulinic acid (5-ALA) within adenine-functionalized supramolecular micelles (A-PPG), in order to achieve effective drug delivery combined with photo-chemotherapy. The resulting DOX/5-ALA-loaded micelles exhibited excellent light and pH-responsive behavior in aqueous solution and high drug-entrapment stability in serum-rich media. A short duration (1–2 min) of laser irradiation with visible light induced the dissociation of the DOX/5-ALA complexes within the micelles, which disrupted micellular stability and resulted in rapid, immediate release of the physically entrapped drug from the micelles. In addition, in vitro assays of cellular reactive oxygen species generation and cellular internalization confirmed the drug-loaded micelles exhibited significantly enhanced cellular uptake after visible light irradiation, and that the light-triggered disassembly of micellar structures rapidly increased the production of reactive oxygen species within the cells. Importantly, flow cytometric analysis demonstrated that laser irradiation of cancer cells incubated with DOX/5-ALA-loaded A-PPG micelles effectively induced apoptotic cell death via endocytosis. Thus, this newly developed supramolecular system may offer a potential route towards improving the efficacy of synergistic chemotherapeutic approaches for cancer.

Near-infrared photon-excited energy transfer in platinum(ii)-based supramolecular polymers assisted by upconverting nanoparticles

2021 ◽  
Vol 57 (15) ◽  
pp. 1927-1930
Author(s):  
Zhao Gao ◽  
Lulu Shi ◽  
Xiao Ling ◽  
Ze Chen ◽  
Qingsong Mei ◽  
...  
Keyword(s):  
Energy Transfer ◽  
Near Infrared ◽  
Supramolecular Polymers ◽  
Upconversion Nanoparticles ◽  
Supramolecular System ◽  
Infrared Photon

A hybrid supramolecular system with near-infrared photon-excited energy transfer has been successfully constructed, relying on the assistance of upconversion nanoparticles in platinum(ii)-based supramolecular polymers.

scholarly journals Bodipy-Loaded Micelles Based on Polylactide as Surface Coating for Photodynamic Control of Staphylococcus aureus

Coatings ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 223
Author(s):  
Enrico Caruso ◽  
Viviana Teresa Orlandi ◽  
Miryam Chiara Malacarne ◽  
Eleonora Martegani ◽  
Chiara Scanferla ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Pathogenic Bacteria ◽  
Surface Coatings ◽  
Supramolecular System ◽  
Amphiphilic Copolymers ◽  
Oxygen Penetration ◽  
Short Period ◽  
Excellent Activity ◽  
Coating Matrix ◽  
Photodynamic Control

Decontaminating coating systems (DCSs) represent a challenge against pathogenic bacteria that may colonize hospital surfaces, causing several important infections. In this respect, surface coatings comprising photosensitizers (PSs) are promising but still controversial for several limitations. PSs act through a mechanism of antimicrobial photodynamic inactivation (aPDI) due to formation of reactive oxygen species (ROS) after light irradiation. However, ROS are partially deactivated during their diffusion through a coating matrix; moreover, coatings should allow oxygen penetration that in contact with the activated PS would generate 1O2, an active specie against bacteria. In the attempt to circumvent such constraints, we report a spray DCS made of micelles loaded with a PS belonging to the BODIPY family (2,6-diiodo-1,3,5,7-tetramethyl-8-(2,6-dichlorophenyl)-4,4′-difluoroboradiazaindacene) that is released in a controlled manner and then activated outside the coating. For this aim, we synthesized several amphiphilic copolymers (mPEG–(PLA)n), which form micelles, and established the most stable supramolecular system in terms of critical micelle concentration (CMC) and ∆Gf values. We found that micelles obtained from mPEG–(PLLA)2 were the most thermodynamically stable and able to release BODIPY in a relatively short period of time (about 80% in 6 h). Interestingly, the BODIPY released showed excellent activity against Staphylococcus aureus even at micromolar concentrations.

scholarly journals A REBCO Persistent-Current Switch (PCS): Test Results and Switch Heater Performance

2017 ◽  
Vol 27 (4) ◽  
pp. 1-5 ◽  
Author(s):  
Philip C. Michael ◽  
Timing Qu ◽  
John Voccio ◽  
Juan Bascunan ◽  
Seungyong Hahn ◽  
...  
Keyword(s):  
Persistent Current ◽  
Test Results ◽  
Current Switch

scholarly journals Design for a Persistent Current Switch Controlled by Alternating Current Magnetic Field

2018 ◽  
Vol 28 (4) ◽  
pp. 1-5 ◽  
Author(s):  
Chao Li ◽  
Jianzhao Geng ◽  
Jamie Gawith ◽  
Boyang Shen ◽  
Xiuchang Zhang ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Alternating Current ◽  
Persistent Current ◽  
Current Switch ◽  
Current Magnetic Field

Experimental study of an inverse wire array z-pinch operating as a current switch

2010 ◽  
Author(s):  
A. Harvey-Thomson ◽  
S. V Lebedev ◽  
G. N. Hall ◽  
S. N. Bland ◽  
G. Burdiak ◽  
...  
Keyword(s):  
Experimental Study ◽  
Wire Array ◽  
Current Switch ◽  
Z Pinch ◽  
A Current

Design Considerations of Packaging a High Voltage Current Switch

2015 ◽  
Author(s):  
Ankan De ◽  
Adam Morgan ◽  
Subhashish Bhattacharya ◽  
Douglas C. Hopkins
Keyword(s):  
High Voltage ◽  
Power Devices ◽  
Variable Parameters ◽  
Package Design ◽  
Current Switch ◽  
Density Distributions ◽  
Design Considerations ◽  
Parasitic Parameters ◽  
Electric Potentials ◽  
Switch Design

In this paper an attempt has been made to demonstrate various package design considerations to accommodate series connection of high voltage Si-IGBT (6500V/25A die) and SiC-Diode (6500V/25A die). The effects of connecting the cathode of the series diode to the collector of the IGBT versus connecting the emitter of the IGBT to the anode of the series diode has been analyzed in regards to gate terminal operation and the parasitic line inductance of the structure. ANSYS Q3D/MAXWELL software have been used to analyze and extract parasitic inductance and capacitances in the package along with electromagnetic fields, electric potentials, and current density distributions throughout the package for variable parameters. SIMPLIS-SIMETRIX is used to simulate typical switch behavior for different parasitic parameters under hard switched conditions. Various simulation results have then been used to redesign and justify the optimized package structure for the final current switch design. The thermal behavior of such a package is also conducted in COMSOL in order to ensure that the thermal ratings of the power devices is not exceeded, and to understand where potentially harmful hotspots could arise and estimate the maximum attainable frequency of operation. The main motivation of this work is to enumerate detailed design considerations for packing a high voltage current switch package.

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