Bottom-up self-assembly

In device fabrication, the location of functional materials is as important as their properties. The integration of solid particles into devices usually requires placing them in specific positions. Hence, the combination of top-down patterning techniques and bottom-up self-assembly is crucial in obtaining (submicron) patterned functional nanostructures on surfaces. 

Fig. 9 Diagram of bottom-up self-assembly approach to nanotechnology, biotechnology, advanced materials, and environmental issues.

Nanotechnology requires a different approach to fabrication from that of microtechnology. Whereas microscale structures are typically formed by top-down techniques (lithography, deposition, etc.), the practical formation of structures at nanoscale dimensions involves additional components, that is, bottom-up self assembly. 

Fig. 10.7 Immobilized Pd nanoparticles by bottom-up self-assembled polymers.

RoteUo and coworkers in an interesting study reported the use of immobilised Pd nanoparticles obtained through polymer mediated bottom-up self-assembly (Fig. 10.7) [25]. Pd clusters stabilised by a mixed monolayer (i.e. Pd MM PC) were... 

Lee B-J, lana SC. Strengthening of polyolefins by bottom-up self-assembly of POSS nanoparticles, ANTEC, conference proceedings. Society of Plastics Engineers 2008. 

For example, LC-organized split ring resonators is presented in Fig. 4.17 [113], where GNPs were trapped in disclination lines surroimding micron sized silica beads that were organized into an array by the nematic continuum phase. There were other developed interesting types of self-assembled nanostructures and it has been claimed that the next frontier toward commercialization was bringing the fabrication cost down with nanochemistry-based bottom-up self-assembly approaches [114]. 

It is understood that nanotechnology is hunting for simple and versatile bottom-up self-assembly-based processes to assemble and (re)organize molecules and/or nanoparticles into well-defined functional superstructures in multiple dimensions over multiple length scales for many advanced technological applications. LCs are emerging as the viable systems for the dynamic self-assembly of nanomaterials in LC media as well as molecular dynamic self-assembly of LC molecules themselves. For example, it has been demonstrated that LCs enable reconfigurable and switchable... 

Although many materials types are available, the main focus is on peptide-based supramolecular systems, since these materials are most frequently utilized in tissue engineering applications. Overall, it is evident that supramolecular systems have great potential in tissue engineering due to their bottom-up self-assembly approach, which employs nanostructured formations to enhance molecular levels interactions with living systems. 

Synthesis macrosurfactants, polysoaps, polyelectrolytes as building blocks preparation of spherical, cylindrical, multicompartment, and schizophrenic micelles, polymer vesicles, polyion complexes bottom-up self-assembly stimuli-sensitive colloids... 

Bottom-up self-assembling nanomaterials-based cartilage constructs... 

In vivo bio-mineralization, the main process involved in the formation of bone tissues, has been exploited in another facile, bottom-up, self-assembling method for processing nanostructured, calcium phosphate (CaP) NPs (Loomba and Sekhon, 2015) and CaP/polymer hybrids (eg, poly(ethylene glycol)-(>-polylactide (PEG-PLA)ZCaP nanocomposites, poly(acrylic acid-fc-isoprene)/CaP hybrid nanocapsules, poly(Af-isopropylacrylamide) (PNlPAAm)/CaP) (Fig. 2.8), the later possessing dual (pH- and thermal-) responsive control over the (drug) release process (Shi et al., 2012). 

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