**2.8 Biopolymeric nanoparticles**

Nano-array of polymer-based nano-conjugates obtained from different natural sources own modern functions besides specific and targeted drug delivery. The natural polymeric reconfigured nanoparticles are biocompatible, less toxic across many bio-membranes against various pH and non-immunogenic and appear to be extra stable to volatile pharmaceutical agents besides offering low-cost fabrication at large-scale/multitude methodology. Biopolymeric reconfigured nanomaterials are biodegradable as anticipated for tissue engineering scaffolds and drug/gene release/ carrier besides novel vaccination approach [3, 19]. Certain natural polymers like chitosan, gelatin and sodium alginate owing to nontoxic profile get easily reconfigurated in situ with man-made polyesters, viz. polycaprolactone, polycyanoacrylate, poly (lactide-co-glycolide), polylactide and polylactic acid, to yield resultant matrixes advocated under advance nano-biotechnology. These bio-polymer-derived nanoparticle offers to develop utility over usual oral/intravenous mode of drug delivery with more competence and efficiency. Certain polymeric nanostructures possess homogeneously dispersed template which can be reconfigurated as vesicular systems like nanocapsules and matrix systems like nanospheres. Reconfigured nanocapsules owe innate cavities that can detain assorted biomoiety including drugs, genes and cells enclosed by polymeric membrane, while nanospheres biomoiety get diffused all over its polymer matrix. Polymeric nanoparticles adopt as globular vesicular nanocapsules wherein polymeric membrane can dissolve, entrap and attach/encapsulate foreign moiety throughout its reconfigured core-matrix/skeleton. Polymeric background is chosen which owns ability of modifications so that resultant nanoparticles can act as ideal carrier/vehicle for delivery of assorted species, viz. drugs, vaccine, contraceptive and antibiotic. Reconfigurated polymeric nanoparticles act as an attractive module for intracellular and site-specific delivery besides engaging in fabricating smart scaffolds/templates in advance tissue engineering [20–23].

## **2.9 Nano-graphynes**

Carbon owing to versatile Dirac cones and hexagonal networking is called as graphyne which exists as α, β and γ forms. Theorized allotrope of carbon called graphyne is found to own carbon-carbon triple bonds pertaining versatile Dirac cones, which aid to perform an astonishing role in reconfigured atomic/electronic structural materials [1, 24]. Such carbon triple bonding adapts hopping template elements with undo signs which yields Dirac cone with perverse chirality in reconfigurated α, β and γ graphynes which impart momentum shift of energy gaps besides offering chemisorption of adatoms via sublattice symmetry loss. Unique characteristics of such 2D carbon nanomaterials can be reconfigured as graphyne and stacking graphdiyne found to stimulate innovative and fascinating utilities in advance electronics. Atomically specific 2D graphdiyne and graphyne matrix reconfiguration is an awaited challenge for material scientists. Technique of on-surface synthesis in ultra-high vacuum yields graphyne that can be further feedstock for making comprehensive graphynes in particular atomically precise graphdiyne nanowires. In the past decades, low-dimension carbon materials, viz. fullerenes, carbon nanotubes and graphene, have ever-fascinated scientific and technological focus. Amid two-dimensional carbon, allotropes called graphene are deliberately pioneered via morphological reconfiguration as porous nano-strips or nanoribbons which own innate bandgap as competitive/superior as graphene. Graphynes are also tentative artificial carbon allotropes owing to intervallic acetylene bondings with blend sp*<sup>n</sup>* hybridization where 1 < *n* < 2. Thus based on sp./sp2 hybridized carbon, such graphynes are categorized as α, β and γ and named as graphyne, graphdiyne and *n-*graphyne where *n* > 2, as per acetylene units [1, 24].

Reconfiguration of single layer, i.e. 2D carbon allotrope graphyne, is still an exigent task, since hardly any natural crystalline substances contain stacked graphynes as inclusive in auxiliary nanostructures like nanotubes, nanoribbons, quantum dots and junctions. The graphyne's innate C-C triple bonding is facile for advanced reconfigurations via attachment of hydrogen/halogen without disturbing innate two-dimensional hexagonal planarity; such reconfiguration tunes energy gap factor

**123**

**Figure 3.**

*Schematic representation of graphyne and graphdiyne matrixes.*

*Nanomaterials via Reconfiguration of Skeletal Matrix DOI: http://dx.doi.org/10.5772/intechopen.86818*

**2.10 Reconfigured graphdiyne nanowire**

at the Dirac point [3, 24]. These graphynes' synthesis is achieved through realistic and choosy functional polymerization owing to diligence precision up to atomic scale, e.g. dehydrobenzoannulenes onto catalytic copper foil via acetylenic crosscoupling resoluted core-graphyne subunits. Dehydrobenzoannulene can also be reconfigurated in assorted morphologies including single-layer graphdiyne, tubes, wires and walls which thrust significant utilities in catalysis and energy field.

Nanoscale graphdiyne-derived templates are developed via Glaser reaction/ acetylenic homocoupling to yield targeted π-conjugated 2D nanomaterials which further can be reconfigured as sp-hybridized nanostructure matrixes [3, 24]. Certain terminal alkynes like 1,3,5-triethynyl-benzene act as convergent tritopic precursors in reconfiguring graphdiyne-based porous matrix via mild thermal annealing. Discriminating butadiyne inspires elementally incarcerated graphdiyne reconfiguration in the form of nanoribbons and *m*-*n* nanowires, where *m* is phenyl rings and *n* is alkynes through the recurring backbone (**Figure 3**). Once side functionality gets established in the graphdiyne moiety, it improves its quality in extended polymerize nanowires, which are best utilized in augmentation of molecular electronic parameters. Graphdiyne nanowires in vacuum own an energy gap of ≈1.6 eV; further statistical twisting of phenylene indicated fine changes in electronics due to cosine highest valence band and lowest conduction band viable for nonlinear electronic transportations like Bloch oscillations appropriate in high-frequency tools. Graphdiyne nanowires proffer notable automatic strength and elasticity if acetylene bondings get well conserved and offer constant chemical characteristics. Superior grade graphdiyne nanowires are prepared using butadiyne precursor through assorted tactics, viz. thermal processing, substrate selectivity, molecular designing, surface templating and metal-organic bonding creations. Raw feedstock selection is crucial in reconfiguration of π-conjugated 2D nanomaterials like graphyne and graphdiyne derivatives. An atom that lies on a surface of crystal acts as the reverse of a surface vacancy and is called as adatom, and it can be cited/reconfigurated onto the top layer of metal surfaces, which impart proactive shell seeking the best adsorption molded molecular deposition and distinguished catalytic properties. On-surface acetylenic glacial coupling using silver metal is suitable to get acetylenic linkages in resultant graphyne and graphdiyne derivatives. Copper and gold both are primal metal for alkyne homocoupling with ditopic 1,4-diethynylbenzene as its over-reactivity gives extra reactions. Gold displayed surprising cyclotrimerization depending on the symmetry of precursors like if three terminal alkynes get mutually coupled to form benzene.

*Nanomaterials via Reconfiguration of Skeletal Matrix DOI: http://dx.doi.org/10.5772/intechopen.86818*

*Nanostructures*

**2.9 Nano-graphynes**

large-scale/multitude methodology. Biopolymeric reconfigured nanomaterials are biodegradable as anticipated for tissue engineering scaffolds and drug/gene release/ carrier besides novel vaccination approach [3, 19]. Certain natural polymers like chitosan, gelatin and sodium alginate owing to nontoxic profile get easily reconfigurated in situ with man-made polyesters, viz. polycaprolactone, polycyanoacrylate, poly (lactide-co-glycolide), polylactide and polylactic acid, to yield resultant matrixes advocated under advance nano-biotechnology. These bio-polymer-derived nanoparticle offers to develop utility over usual oral/intravenous mode of drug delivery with more competence and efficiency. Certain polymeric nanostructures possess homogeneously dispersed template which can be reconfigurated as vesicular systems like nanocapsules and matrix systems like nanospheres. Reconfigured nanocapsules owe innate cavities that can detain assorted biomoiety including drugs, genes and cells enclosed by polymeric membrane, while nanospheres biomoiety get diffused all over its polymer matrix. Polymeric nanoparticles adopt as globular vesicular nanocapsules wherein polymeric membrane can dissolve, entrap and attach/encapsulate foreign moiety throughout its reconfigured core-matrix/skeleton. Polymeric background is chosen which owns ability of modifications so that resultant nanoparticles can act as ideal carrier/vehicle for delivery of assorted species, viz. drugs, vaccine, contraceptive and antibiotic. Reconfigurated polymeric nanoparticles act as an attractive module for intracellular and site-specific delivery besides engaging in fabricating smart scaffolds/templates in advance tissue engineering [20–23].

Carbon owing to versatile Dirac cones and hexagonal networking is called as graphyne which exists as α, β and γ forms. Theorized allotrope of carbon called graphyne is found to own carbon-carbon triple bonds pertaining versatile Dirac cones, which aid to perform an astonishing role in reconfigured atomic/electronic structural materials [1, 24]. Such carbon triple bonding adapts hopping template elements with undo signs which yields Dirac cone with perverse chirality in

reconfigurated α, β and γ graphynes which impart momentum shift of energy gaps besides offering chemisorption of adatoms via sublattice symmetry loss. Unique characteristics of such 2D carbon nanomaterials can be reconfigured as graphyne and stacking graphdiyne found to stimulate innovative and fascinating utilities in advance electronics. Atomically specific 2D graphdiyne and graphyne matrix reconfiguration is an awaited challenge for material scientists. Technique of on-surface synthesis in ultra-high vacuum yields graphyne that can be further feedstock for making comprehensive graphynes in particular atomically precise graphdiyne nanowires. In the past decades, low-dimension carbon materials, viz. fullerenes, carbon nanotubes and graphene, have ever-fascinated scientific and technological focus. Amid two-dimensional carbon, allotropes called graphene are deliberately pioneered via morphological reconfiguration as porous nano-strips or nanoribbons which own innate bandgap as competitive/superior as graphene. Graphynes are also tentative artificial carbon allotropes owing to intervallic acetylene bondings with

hybridization where 1 < *n* < 2. Thus based on sp./sp2

and *n-*graphyne where *n* > 2, as per acetylene units [1, 24].

such graphynes are categorized as α, β and γ and named as graphyne, graphdiyne

Reconfiguration of single layer, i.e. 2D carbon allotrope graphyne, is still an exigent task, since hardly any natural crystalline substances contain stacked graphynes as inclusive in auxiliary nanostructures like nanotubes, nanoribbons, quantum dots and junctions. The graphyne's innate C-C triple bonding is facile for advanced reconfigurations via attachment of hydrogen/halogen without disturbing innate two-dimensional hexagonal planarity; such reconfiguration tunes energy gap factor

hybridized carbon,

**122**

blend sp*<sup>n</sup>*

at the Dirac point [3, 24]. These graphynes' synthesis is achieved through realistic and choosy functional polymerization owing to diligence precision up to atomic scale, e.g. dehydrobenzoannulenes onto catalytic copper foil via acetylenic crosscoupling resoluted core-graphyne subunits. Dehydrobenzoannulene can also be reconfigurated in assorted morphologies including single-layer graphdiyne, tubes, wires and walls which thrust significant utilities in catalysis and energy field.
