Milliseconds Make the Difference in the Far-from-Equilibrium Self-Assembly of Supramolecular Chiral Nanostructures

2016 ◽  
Vol 138 (22) ◽  
pp. 6920-6923 ◽  
Author(s):  
Alessandro Sorrenti ◽  
Romen Rodriguez-Trujillo ◽  
David B. Amabilino ◽  
Josep Puigmartí-Luis
Keyword(s):  
Self Assembly ◽  
Far From Equilibrium ◽  
The Difference ◽  
Chiral Nanostructures

Bioenergetics of Na+ transport across frog skin: chemical and electrical measurements

1983 ◽  
Vol 245 (6) ◽  
pp. F691-F700 ◽  
Author(s):  
M. M. Civan ◽  
K. Peterson-Yantorno ◽  
D. R. DiBona ◽  
D. F. Wilson ◽  
M. Erecinska
Keyword(s):  
Free Energy ◽  
Frog Skin ◽  
Atp Hydrolysis ◽  
Transepithelial Transport ◽  
Base Line ◽  
Free Energies ◽  
Electrical Measurements ◽  
Far From Equilibrium ◽  
The Difference ◽  
Hydrolysis Of

Enzymatically prepared split frog skins consisted purely of epithelial cells. Electrical parameters and the cell contents of ATP, ADP, phosphocreatine (PCr), creatine, inorganic phosphate, protein, and water were measured in skins maintained at room temperature. Studies were conducted under base-line conditions, 15 and 60 min after adding vasopressin, and 30 min after adding amiloride. Intracellular ionic activities and concentrations were obtained from previous results. The data demonstrated that 1) the base-line concentration ratio of PCr/ATP was 0.53 +/- 0.03; 2) the average molar free energy of hydrolysis of intracellular ATP was approximately 15.0 kcal X mol-1 under control conditions, changing by less than or equal to 3% with changes in transport; and 3) the free energy of extruding 3 mol of Na+ and accumulating 2 mol of K+ was approximately 9.8 kcal X mol-1 under base-line conditions; the difference between the molar free energies of ATP hydrolysis and of transport work remained large, despite large changes in transepithelial transport. The simplest conclusion is that the Na+ pump of frog skin operates far from equilibrium.

scholarly journals Towards Building Blocks for Supramolecular Architectures Based on Azacryptates

Molecules ◽  
2020 ◽  
Vol 25 (7) ◽  
pp. 1733 ◽  
Author(s):  
Ana Miljkovic ◽  
Sonia La Cognata ◽  
Greta Bergamaschi ◽  
Mauro Freccero ◽  
Antonio Poggi ◽  
...  
Keyword(s):  
Conformational Changes ◽  
Self Assembly ◽  
Hydrophobic Interactions ◽  
Building Blocks ◽  
Water Mixture ◽  
Molecular Systems ◽  
Supramolecular Architectures ◽  
Starting Point ◽  
The Difference ◽  
Supramolecular Devices

In this work, we report the synthesis of a new bis(tris(2-aminoethyl)amine) azacryptand L with triphenyl spacers. The binding properties of its dicopper complex for aromatic dicarboxylate anions (as TBA salts) were investigated, with the aim to obtain potential building blocks for supramolecular structures like rotaxanes and pseudo-rotaxanes. As expected, UV-Vis and emission studies of [Cu2L]4+ in water/acetonitrile mixture (pH = 7) showed a high affinity for biphenyl-4,4′-dicarboxylate (dfc2−), with a binding constant of 5.46 log units, due to the best match of the anion bite with the Cu(II)-Cu(II) distance in the cage’s cavity. Compared to other similar bistren cages, the difference of the affinity of [Cu2L]4+ for the tested anions was not so pronounced: conformational changes of L seem to promote a good interaction with both long (e.g., dfc2−) and short anions (e.g., terephthalate). The good affinity of [Cu2L]4+ for these dicarboxylates, together with hydrophobic interactions within the cage’s cavity, may promote the self-assembly of a stable 1:1 complex in water mixture. These results represent a good starting point for the application of these molecular systems as building units for the design of new supramolecular architectures based on non-covalent interactions, which could be of interest in all fields related to supramolecular devices.

Self-Assembly of Hierarchical Chiral Nanostructures Based on Metal-Benzimidazole Interactions: Chiral Nanofibers, Nanotubes, and Microtubular Flowers

Small ◽  
2016 ◽  
Vol 12 (34) ◽  
pp. 4743-4752 ◽  
Author(s):  
Xiaoqin Zhou ◽  
Qingxian Jin ◽  
Li Zhang ◽  
Zhaocun Shen ◽  
Long Jiang ◽  
...  
Keyword(s):  
Self Assembly ◽  
Chiral Nanostructures

scholarly journals Globular pattern formation of hierarchical ceria nanoarchitecture

2021 ◽  
Author(s):  
Noboru Aoyagi ◽  
Ryuhei Motokawa ◽  
Masahiko Okumura ◽  
Takumi Saito ◽  
Shotaro Nishitsuji ◽  
...  
Keyword(s):  
Self Assembly ◽  
Dissipative Structures ◽  
Ordered Structures ◽  
Seed Formation ◽  
Acidic Aqueous Solution ◽  
Multiphase Mixture ◽  
Stability And Instability ◽  
Primary Core ◽  
Far From Equilibrium ◽  
Crystal Seed

Abstract Dissipative structures often appear as an unstable counterpart of ordered structures owing to fluctuations that do not form a homogeneous phase. Even a multiphase mixture may simultaneously undergo one chemical reaction near equilibrium and another one that is far from equilibrium. Here, we observed in real time crystal seed formation and simultaneous nanocrystal aggregation proceeding from CeIV complexes to CeO2 nanoparticles in an acidic aqueous solution, and investigated the resultant hierarchical nanoarchitecture. The formed particles exhibited two very different size ranges. The hierarchically assembled structures in solutions were CeO2 colloids, viz. primary core clusters (1–3 nm) of crystalline ceria and secondary clusters (20–30 nm) assembled through surface ions. Such self-assembly is widespread in multi-component complex fluids, paradoxically moderating hierarchical reactions. Stability and instability are not only critical but also complementary for co-optimisation around the nearby free energy landscape prior to bifurcation.

Development of an Electron Scattering Model to Detect Differences in DNA Base Molecules

2011 ◽  
Author(s):  
Yuki Nishioka ◽  
Kentaro Doi ◽  
Satoyuki Kawano
Keyword(s):  
Theoretical Model ◽  
Electric Conductivity ◽  
Electron Scattering ◽  
Self Assembly ◽  
High Speed ◽  
Classical Electrodynamics ◽  
Base Pairs ◽  
Novel Technologies ◽  
Dna Base ◽  
The Difference

In recent, novel technologies which apply bio-macromolecules to bio-nanodevices attract much attention. Particularly, DNAs have several desirable characteristics: complementary base pairs, self assembly, and electric conductivity. It is expected that high-speed DNA sequencers can be developed by using these specific characteristics of DNAs. In the present study, we develop a theoretical model to analyze the difference of DNA base molecules, in which electron scattering is simulated based on classical electrodynamics and scattering angles are evaluated. Consequently, it is found that scattering angles of the scattered electrons are clearly different from each other.

scholarly journals Light-fueled transient supramolecular assemblies in water as fluorescence modulators

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Xu-Man Chen ◽  
Xiao-Fang Hou ◽  
Hari Krishna Bisoyi ◽  
Wei-Jie Feng ◽  
Qin Cao ◽  
...  
Keyword(s):  
Self Assembly ◽  
Thermal Dissociation ◽  
Hepatocellular Cancer ◽  
Supramolecular Assembly ◽  
Supramolecular Assemblies ◽  
Light Power ◽  
Highly Sensitive ◽  
Supramolecular Nanoparticles ◽  
Far From Equilibrium ◽  
Over Time

AbstractDissipative self-assembly, which requires a continuous supply of fuel to maintain the assembled states far from equilibrium, is the foundation of biological systems. Among a variety of fuels, light, the original fuel of natural dissipative self-assembly, is fundamentally important but remains a challenge to introduce into artificial dissipative self-assemblies. Here, we report an artificial dissipative self-assembly system that is constructed from light-induced amphiphiles. Such dissipative supramolecular assembly is easily performed using protonated sulfonato-merocyanine and chitosan based molecular and macromolecular components in water. Light irradiation induces the assembly of supramolecular nanoparticles, which spontaneously disassemble in the dark due to thermal back relaxation of the molecular switch. Owing to the presence of light-induced amphiphiles and the thermal dissociation mechanism, the lifetimes of these transient supramolecular nanoparticles are highly sensitive to temperature and light power and range from several minutes to hours. By incorporating various fluorophores into transient supramolecular nanoparticles, the processes of aggregation-induced emission and aggregation-caused quenching, along with periodic variations in fluorescent color over time, have been demonstrated. Transient supramolecular assemblies, which act as fluorescence modulators, can also function in human hepatocellular cancer cells.

When Interface Gets Rough…

1994 ◽  
Vol 367 ◽  
Author(s):  
Toh-Ming Lu ◽  
Hong-Ning Yang ◽  
Gwo-Ching Wang
Keyword(s):  
Thin Film ◽  
Film Growth ◽  
Interface Roughness ◽  
Affine Scaling ◽  
Dynamic Scaling ◽  
Local Slope ◽  
Scaling Hypothesis ◽  
Approaches To Study ◽  
Far From Equilibrium ◽  
The Difference

AbstractInterface roughness is one of the central features in many important thin film technologies. Roughness is a result of far from equilibrium dynamic growth process and is difficult to describe using conventional statistical mechanics. Recently a dynamic scaling hypothesis has been proposed to describe such a system in which both time and space scaling are considered simultaneously. This approach has generated tremendous interest, both theoretical and experimental, for scientists working in thin film growth/etching as well as many diverse fields. In this paper we shall discuss the origin of the formation of interface roughness, the difference between near equilibrium and far from equilibrium growth problems, the relevant parameters that are necessary to describe a rough interface, and the application of the self-affine scaling concept in growth problems. The experimental approaches to study rough interfaces and growth fronts using diffraction will be summarized. It is shown that there exist two types of dynamic scaling during growth, one with a stationary local slope and another one with a nonstationary local slope. Future directions in this new area of research are highlighted.

scholarly journals Exploring the Adsorption Mechanism of Tetracene on Ag(110) by STM and Dispersion-Corrected DFT

Crystals ◽  
2019 ◽  
Vol 10 (1) ◽  
pp. 13 ◽  
Author(s):  
Zhaofeng Liang ◽  
Qiwei Tian ◽  
Huan Zhang ◽  
Jinping Hu ◽  
Pimo He ◽  
...  
Keyword(s):  
Molecular Electronics ◽  
Self Assembly ◽  
Density Functional ◽  
Scanning Tunneling ◽  
Dispersion Force ◽  
Tunneling Microscopy ◽  
Functional Theory ◽  
Silver Substrate ◽  
The Difference ◽  
Low Dimensional

Self-assembled strategy has been proven to be a promising vista in constructing organized low-dimensional nanostructures with molecular precision and versatile functionalities on solid surfaces. Herein, we investigate by a combination of scanning tunneling microscopy (STM) and dispersion-corrected density functional theory (DFT), the adsorption of tetracene molecules on the silver substrate and the mechanism mediating the self-assembly on Ag(110). As expected, ordered domain is formed on Ag(110) after adsorption with adjacent molecules being imaged with alternating bright or dim pattern regularly. While such behavior has been assigned previously to the difference of molecular adsorption height, herein, it is possible to investigate essentially the mechanism leading to the periodic alternation of brightness and dimness for tetracene adsorbed on Ag(110) thanks to the consideration of Van der Waals (vdW) dispersion force. It is demonstrated that the adsorption height in fact is same for both bright and dim molecules, while the adsorption site and the corresponding interfacial charge transfer play an important role in the formation of such pattern. Our report reveals that vdW dispersion interaction is crucial to appropriately describe the adsorption of tetracene on the silver substrate, and the formation of delicate molecular architectures on metal surfaces might also offers a promising approach towards molecular electronics.

Sign in / Sign up

Export Citation Format

Share Document