Nanoparticles fabrication

Recently, many studies have focused on self-assembled biodegradable nanoparticles for biomedical and pharmaceutical applications. Nanoparticles fabricated by the self-assembly of amphiphilic block copolymers or hydrophobically modified polymers have been explored as drug carrier systems. In general, these amphiphilic copolymers consisting of hydrophilic and hydrophobic segments are capable of forming polymeric structures in aqueous solutions via hydrophobic interactions. These self-assembled nanoparticles are composed of an inner core of hydrophobic moieties and an outer shell of hydrophilic groups [35, 36]. 

McAllister D, et al. Microfabricated needles for transdermal delivery of macromolecules and nanoparticles fabrication methods and transport studies. Proc Natl Acad Sci USA 2003 24 13755-13760. 

The resolution of SEMs is now suitable for nano-materials characterization. High resolution SEM is a powerful instrument for imaging fine structures of materials and nanoparticles fabricated by nanotechnology. In lens SE, BSE modes, and STEM mode are often performed to check the structure of CNT growths or CNT as delivered by commercial producers, and sometimes coupled with TEM. Even the single-walled carbon nanotubes can easily be observed by HR-SEM (see Figure 3.13). The STEM mode can also be used for free CNT observation (75). 

Zhang, Z. Feng, S. S. In vitro investigation on poly(lactide)-Tween 80 copolymer nanoparticles fabricated by dialysis method for chemotherapy. Biomacromolecules 2006, 7, 1139-1146. 

Nanoparticles fabricated in such a way possess a good adhesion to the surface. Previously it was shown that surface relief strongly affects the topology of gold deposition. A pretextured semiconductor surfaces can be used as templates for ID, 2D ordered nanostructure fabrication [4]. The polished (100) surfaces of n-GaAs single crystal were used for the metal deposition. Typical gold nanoparticle ensembles are shown in Fig. la. Silver nanoparticles (Fig. lb) are of 30 - 60 nm in diameter and uniformly cover the surface. 

Zarrabi, A., M. Vossoughi, 1. Alemzadeh, and M.R. Chitsazi. Monodispersed polymeric nanoparticles fabrication by electrospray atomization. International Journal of Polymeric Materials and Polymeric Biomaterials 61(8) (2012) 611-626. 

Mayo, A.S., Ambati, B.K., and Kompella, U.B. Gene delivery nanoparticles fabricated by supercritical fluid extraction of emulsions. International Journal of Pharmaceutics 387 (2010) 278-285. 

Nanoparticles fabricated from PGA have also shown some tremendous promise as viral carriers for tumor vaccines. Earlier studies have shown that they can deliver antigens at significantly higher amounts to antigen-presenting cells as controls. Enhanced downstream effect and increased immune response were observed in antigen-specific cytotoxic T lymphocytes [264-266]. Similar nanoparticles have been synthesized with PGA in the backbone [267]. The surface charge and the hydrophilicity of the PGA are some of the characteristics that have been exploited in such... 

Nanoparticle fabrication includes methods such as solvent evaporation, spontaneous emulsification, solvent diffusion, salting out/emulsification diffusion, and polymerization techniques [24]. The synthesis method can greatly impact the particle s physical, chemical, and biological properties and the dispersion and stability of the particles, which are important considerations in biomedical applications. The nanoparticle size and shape is of great importance because the internalization, circulation, distribution, and targeting aspects of the system can be affected by these characteristics [5]. 

These methods have been widely used for nanoparticle fabrication techniques. These methods have been widely utilized for nanoparticles fabrication techniques which was subjected for both vaporization and condensation techniques. This method can play a vital role in both physical and chemical methods of synthesis of nanoparticles. The synthesized nanoparticles are subjected to various characterization techniques to identify whether they are the same size, if they are the same size the preparation method is physical vapor condensation. But if they are different particle sizes then we can conclude it with physical vapor condensation (Ghorbani et al., 2011). 

Purwanto, A. Wang, W. N. Ogi, T. Lenggrao, I. W. Tanabe, E. Okuyama, K. High luminance YAG Ce nanoparticles fabricated frran urea added aqueous precursor by flame process. Journal of Alloys and Compounds 2008,463, 350-357. 

Surface-Enhanced Raman Spectroscopy, Fig. 4 Overview of the broad diversity of SERS substrates (a) aggregates of silver nanoparticles fabricated by means of a modified Lee-Meisel protocol, (b) aggregates of gold nanoparticles, (c) enzymatic generated silver nanoparticles with flowerlike shape, (d) nanosized gold cores coated by a silica shell for an application as SERS label, (e) silver nanotriangle structures prepared by means... 

FIGURE 8.63 Transmission and scanning electron microscope images of PPy nanoparticles and hollow nanospheres (a) soluble PPy nanoparticles fabricated using 0.45 M DeTAB (b) linear PPy/crosslinked PPy core/shell nanoparticles (c) PPy nanocapsules (d) carbon nanocapsules (inset a HRTEM image of the wall). (From Jang, J.S., Li, X.L., and Oh, J.H., Chem. Commun., 794, 2004. With permission.)... 

Microemulsions [191, 192] are transparent, optically isotropic and thermodynamically stable liquids. They contain dispersion of polar and nonpolar solvent, usually water or aqueous solutions and oils. Adding surfactants stabilizes droplets of 1-100 nm in size. Due to amphiphilic properties of the surface active substances containing lipophilic groups and one or two lyophobic C-H chains mainly collected at the interface of two liquid phases, they cannot be mixed under normal conditions. Unlike traditional macroemulsion, which is kinetically stabilized only by the external mechanical energy supply, nano-domains in the microemulsions are formed spontaneously. Their size depends on the microemulsion composition, temperature and elastic properties of the separating film of surfactant. In particular, in the case of water-oil microemulsions with spherical nanosized micelles of water dispersed in oil, water droplets can be used as nanoreactors and templates for the solid nanoparticles fabrication. Since the reaction is initiated by the spatially restricted water and micelle, heterogeneous nucleation and crystal growth can be controlled. 

The fifth chapter presents detailed review of technological aspects of ferroic nanoparticles fabrication. We present the detailed information about methods of chemical synthesis of above nanoparticles. Among them are hydrothermal, sol-gel and coprecipitation methods. We also present the method of unstable compounds decomposition. The combined synthesis methods have also been discussed. Namely, we consider mechanochemical, sonochemical and template synthesis methods. The main idea of these methods is to control the dispersity and agglomeration degree of nanoparticles by inspection of nucleation and growth of a new phase. Self-assembly and self-organization of ferroic nanoparticles as well as composites formation on their base by means of colloidal processes have also been considered. 

Recent advanees in nanotechnology that enable the improved produetion and eontrol of nanoparticle fabrication have had and will have signifieant impact on... 

Hang AT, Tae B, Park JS (2010) Non-woven mats of poly(vinyl alcohol)/chitosan blends containing silver nanoparticles fabrication and characterization. Carbohydr Polym 82 472-479... 

Russo L, Colangelo F, Cioffi R, Rea I, De Stefano L (2011) A mechano-chemical approach to porous silicon nanoparticles fabrication. Materials 4 1023-1033 Stephen RG, Riley FL (1989) Oxidation of silicon by water. J Eur Ceram Soc 5 219-222 Stevulova N, Suzuki T, Senna M, Balintova M, Sepelak V, Tkacova K (1997) Mechanochemical oxidation of silicon and selectivity of oxide superficial layer dissolution in aqueous solutions of HF and KOH. Solid State Ion 101103(2) 681-686 Verdoni LP, Fink MJ, Mitchell BS (2011) A fractionation process of mechanochemically synthesized blue-green luminescent alkyl-passivated silicon nanoparticles. Chem Eng J 172 591-600... 

Russo L, Colangelo F, Cioffi R, Rea I, De Stefano L (2011) A mechanochemical approach to porous silicon nanoparticles fabrication. Material 4 1023-1033... 

There are a lot of chemical, biochemical, physical and chemical methods of nanoparticle fabrication assigned to produce compounds of different nature localized in different parts of capsules. 

The chapter has described combinatorial libraries of biomaterials that are useful for genetic nanomedicine. High-throughput synthesis and screening methods were discussed that allow for parallel nanoparticle fabrication and cell-based testing. Important... 

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