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The Advantages and Versatility of Carrier-Free Nanodrug and Nanoparticle Systems for Cancer Therapy
Published in Loutfy H. Madkour, Nanoparticle-Based Drug Delivery in Cancer Treatment, 2022
Self-assembly as a drug carrier: Molecular self-assembly is a free energy-driven process that spontaneously organizes molecules into ordered structures in multiple geometries. Therefore, self-assembly is a very attractive approach to constructing nanoscale-based bioactive materials due to its straightforward use in biomedical applications, including tissue engineering, regenerative medicine, and drug delivery. The great advantage of self-assemblies is their structural features, which can be tuned through molecular chemistry and environmental conditions (pH, ionic strength, solvents, and temperature) [369]. Self-assembly of the photosensitizer (chlorin e6, Ce6) and a chemotherapeutic agent (DOX) linked with electrostatic, π–π stacking, and hydrophobic interactions is designed to inhibit tumor recurrence (Figure 1.17a). Intravenously administered free Ce6 and NPs were distributed throughout the body, whereas the administered self-assembly drugs accumulated in the tumor site exclusively (Figure 1.17b). Ex vivo imaging of excised tumors further confirmed higher drug accumulation in tumors with NPs than with free Ce6 solution (Figure 1.17c) [370].
Advances in the Processing and Fabrication of Bioinspired Materials and Implications by Way of Applications
Published in T. S. Srivatsan, T. S. Sudarshan, K. Manigandan, Manufacturing Techniques for Materials, 2018
Lakshminath Kundanati, Nicola M. Pugno
Most of the biological processes are driven by self-assembly right from deoxyribonucleic acid, viruses, proteins, and cell membranes. These processes are an orchestra of molecules organized at nanometer scale under equilibrium conditions to form stable aggregates (Whitesides et al. 1991). Thus, molecular self-assembly has become a crucial route to make bioinspired materials because of its ability to fabricate materials with higher complexity and precision, to achieve multifunctionality (Mendes et al. 2013). At the molecular level, the interactions can be driven by electrostatic interactions, aromatic interactions, hydrophobic effects, and hydrogen bonding. For example, proteins can be seen as self-assembled chains built by the primary building blocks called peptides, and their folding is mitigated by self-assembly with the help of noncovalent interactions in aqueous solution. Protein folding is a very important phenomenon that enables folding of proteins into 3D structures ubiquitous in biological self-assembly. It is one of most critical process in biological systems that led to enormous diversity by selectively influencing particular chemical pathways (Dobson 2002).
Self-assembled Peptide Nanostructures and Their Applications
Published in Klaus D. Sattler, st Century Nanoscience – A Handbook, 2020
Molecular self-assembly is a spontaneous process in which molecules in a nonaggregated state transform to a well-defined ordered organized state. Though self-assembly is a spontaneous process, the morphology can be controlled by tuning external parameters. Several external stimuli like solvent, temperature, concentration, pH, ionic strength, ultrasound, shaking, and stirring are responsible for tuning the nanostructures (Lowik et al. 2010, Mart et al. 2006). Liu et al. have reviewed the control of molecular design and external stimuli to tune the morphologies of the nanostructures in self-assembled supramolecular gels (Zhang et al. 2014). Thus, here, we have discussed the tuning of self-assembled peptide nanostructures by controlling the external parameters (Figure 2.4).
Molecular scale insights from NMR studies of hybrid systems formed via doping silver QDs in 6CHBT liquid crystal: a quantitative investigation of their optoelectronic properties
Published in Liquid Crystals, 2023
Archana Kumari Singh, Satya Pal Singh
Soft Matter includes polymers, colloids, liquid crystals, and granular materials [1,2]. Nanoparticles used in biomedical applications interact with biological fluids, forming a biomolecular corona that can affect their behaviour. Supramolecular self-assembly is a fascinating natural process driven by characteristic moieties in chemical structures. Aggregates formed through self-assembly control the macroscopic properties of materials, offering unique functionalities like self-healing and shape-memory. Understanding the origin of molecular self-assembly is crucial for exploring its correlations with chemical structure [3,4] and finding new hierarchical structures with tailored functional properties. The process of molecular self-assembly is governed by supramolecular interactions (ionic, hydrophobic, van der Waals, hydrogen, and coordination bonds), but it can also be directed by kinetically labile covalent bonds [5–8]. Ionic Liquid Crystals (ILCs) have recently attracted much attention [9–11]. The presence of both polar and non-polar areas in the cations causes the material to create distinct regions or domains. These regions can interact with neighbouring molecules or ions in multiple ways, contributing to the stability of mesophase. The polar and non-polar regions might interact differently with other components or external stimuli, affecting the overall behaviour and qualities of the material.
Perspective on structure-property relationship of room temperature single-component liquid crystals
Published in Liquid Crystals, 2022
Govindaswamy Shanker, K. R. Sunil Kumar, Bishwajit Paul
It is difficult to pre-empt the driving forces of molecular self-assembly with the precise balance of shape, volume ratio, and intermolecular interactions of the molecules. Nevertheless, the parametrising LCs fought with complexity and the rational design of mesophase at room temperature remains untenable. Despite the difficulty in identifying the exact ‘patterning’ of the aromatic core with lateral/terminal substituents that might induce LC properties, it is still possible to understand the stochastic nature of RT-SLC identification by summarising the above literature studies. Additionally, there is no good database in LC literature that can assist anyone entering the field in choosing their starting point. Our review might be a small effort towards this, which might prod the LC community to devise LC database. The promising lead of highly crystalline compounds can only come from authenticated database for crafting better LCs. Furthermore, the traditional method of LC screening includes differential scanning calorimetry, polarised optical microscopy, and X-ray diffraction studies. Unfortunately, none can be tailored for high throughput screening. These shortcoming might look prohibitory signs of LC works but we feel LC research is poignantly placed in a zone where the pace of getting new LCs with RT thermal behaviour might be still be worth investigating.
Is order creation through disorder in additive manufacturing possible?
Published in Cogent Engineering, 2021
Frédéric Demoly, Jean-Claude André
On this basis, it is possible to think that one will be able to master matter, in its most intimate elements, so that it transforms itself to reach a given form and functionality. This is what we find in the science fiction film “Terminator 2”. The generic idea is based on the concept of self-organization, where a system composed of elementary components assembles and organizes itself spontaneously and autonomously, following specific and local interactions between these components. Molecular self-assembly occurs when the components are molecules or supramolecular elements. The transformation of matter to reach a given shape is possible if the number of operations to be performed on it is as limited as possible, hence the exemplary realization of nanometric objects. Indeed, stimulated “self-organization” phenomena can become sensitive, far from equilibrium, to factors considered negligible near equilibrium. It is the intrinsic activity of the increasingly complex system, increasingly non-linear in its behaviour, that determines how it is possible to describe its relationship to the environment, thus generating the type of intelligibility that will be relevant to understand its possible histories.