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Near-Infrared Organic Materials for Biological Applications
Published in Song Sun, Wei Tan, Su-Huai Wei, Emergent Micro- and Nanomaterials for Optical, Infrared, and Terahertz Applications, 2023
In addition to the two strategies described above to achieve NIR organic compounds by covalent synthesis and fabrication, there is also a supramolecular approach for tuning the HLEGs of organic chromophores. Supramolecular chemistry refers to the chemistry beyond the molecules, which employs noncovalent interactions and recognitions to construct well-defined assemblies and nanostructures [8–15]. Compared with traditional synthetic strategies, supramolecular methods have unique advantages in two primary aspects. The first one is the elimination of tedious organic synthesis by using of intermolecular self-assembly approach. The second superiority is the tunability, reversibility and adaptation, which arise from the dynamic and noncovalent nature of the intermolecular interactions. In this section, several typical supramolecular systems, including supramolecular charge transfer complex, aggregates, and organic radicals, will be introduced and discussed for their abilities to lower HLEGs and gain NIR activities.
Self-assembled Peptide Nanostructures and Their Applications
Published in Klaus D. Sattler, st Century Nanoscience – A Handbook, 2020
A famous quotation by Richard Feynman during a lecture entitled “there’s plenty of room at the bottom” generated an idea for “bottom–up” approach for the fabrication of higher ordered structures via self-assembly process using individual atoms and molecules as building blocks (Feynman 1959). In supramolecular chemistry, the construction of molecules with well-defined design has potential applications in various fields of chemistry and material sciences. Generally, the bottom–up approach is the arrangement of smaller components into a more complex assembly (Zhang 2003a). These techniques are often similar to a “seed” model, in which the starting material is small but eventually grows in complexity and completeness. Normally, the molecular assembly process is based on the bottom–up technique that helps in developing and constructing the higher ordered functional materials. Natural bioactive macromolecules and bioarchitectures like amino acids, sugars, nucleic acids or lipids are the building blocks for the development of higher ordered self-assembled functional materials by using bottom–up strategies. Now, the design of self-assembled supramolecular structures of peptides, proteins, and other amphiphiles includes tapes (Anilkumar and Jayakannan 2009), belts (Cui et al. 2009), fibers (Komatsu et al. 2009), tubes (Childers et al. 2010), and vesicles (Koley et al. 2011). The bottom–up approach is the most useful technique to construct different nanostructures.
Supramolecular Chemistry
Published in Mihai V. Putz, New Frontiers in Nanochemistry, 2020
Most importantly, however, the concepts of supramolecular (multicomponent) chemistry can be profitably used to design and construct a great variety of artificial compounds capable of performing useful functions. It is amazing to notice that the bottom-up approach to the construction supramolecular systems was poetically anticipated by Primo Levi in his book The Monkey’s Wrench (Levi, 1995): “It is reasonable to proceed a bit at a time, first attaching two pieces, then adding a third, and so on. … we don’t have those tweezers we often dream of at night…. If we had those tweezers (and it’s possible that one day, we will), we would have managed to create some lovely things that so far only the Almighty has made, for example, to assemble – perhaps not a frog or a dragonfly – but at least a microbe or the spore of a mold.” Up until now, nobody has succeeded to construct a chemical system as complex as a microbe or the spore of mold. In recent years, however, a number of very simple molecular-level devices and machines have been build up by exploiting the principles of supramolecular chemistry, namely 1) compounds for transfer, transport, and collection of electrons or electronic energy; 2) multistate/multifunctional systems; and 3) compounds capable of performing mechanical movements (machines) (Balzani et al., 2008). This outstanding progress shows that looking at supramolecular chemistry from the viewpoint of functions with references to devices and machines of the macroscopic world, is a very interesting exercise that introduces novel concepts, injects daring ideas, and stimulates creativity in the fields of chemistry and nanotechnology.
The impact of sodium salts on the physicochemical properties of the mixture of tetradecyltrimethylammonium bromide and metformin hydrochloride drug at several temperatures
Published in Molecular Physics, 2022
Roksanur Akter, Shamim Mahbub, M. Alfakeer, Md. Tuhinur R. Joy, Md. Niaz Ishtiak, Shahed Rana, Dileep Kumar, Md. Anamul Hoque
Supramolecular structures and materials play a wide role in therapeutic drug delivery, drug carriers, optimised target and controlled release; this is possible for the thorough study of the inception and development of supramolecular chemistry. Surfactants have enormous usages in biology, technology, basic research and industries [1,2]. The role is still elusive as to how their structural integrity and morphological stability impact in-vivo performances [3]. Many orally administered drugs with low solubility in the aqueous medium (a traditional standard medium in the biopharmaceutics classification system) must initially overwhelm biological difficulty produced by an intestinal barrier. Solubility has often discussed the rate-limiting step with the purpose of controlling the amount of absorption. Micellar solubilisation increases the solubility in an aqueous medium as they enhance wettability [4].
Diastereomeric discrimination by achiral substances: the effect of diverse ions in the stability of amphi-ionophore cystine-based cyclopeptide stereoisomers
Published in Molecular Physics, 2019
Samaneh Ahmadi, Hossein A. Dabbagh, Saeid Ebrahimi, Hossein Farrokhpour
Supramolecular chemistry is one of the most attractive and important subjects in chemistry, biochemistry as well as material science. The beginning of supramolecular chemistry is with the discovery of crown ether macromolecules by Pedersen in 1967 [1]. Host-guest system is one of the broad categories of supramolecular structure, in which the smaller ‘guest’ molecules held in large ‘host’ molecules. The most common host molecules are cyclodextrins [2], cavitands [3] calixarens [4], pillararenes [5], and proteins [6]. The binding of the host with the guest in supramolecular host-guest systems occurs via a different kind of non-covalent interaction, such as electrostatic, hydrogen bonding, hydrophobicity, and dispersion interactions [7,8]. These non-covalent interactions are responsible for many important chemical and biological phenomena [9] and have been subjected to many theoretical [10,11] and experimental [12] viewpoints.
Gelation properties of amino-acid-based bis-urea compounds in organic solvents and in the presence of surfactants
Published in Soft Materials, 2023
Kyra Danielle C. Magdato, Monissa C. Paderes
Many industries, including biomedical,[1–6] cosmetics,[7–10] personal care,[11,12] optoelectronics,[13–15] sensors,[16–18] and energy storage and generation,[14,19,20] have benefited from advances in supramolecular chemistry. However, despite success in the construction of supramolecular materials, the challenge of creating more complex and multi-responsive architectures remains.[21] Highly functionalized materials have been used to create more intricate supramolecular structures, but rational design and preparation of these chemical entities require a significant amount of time and effort.[22,23]