Nanoparticles, biological hybrid

Composite materials are of interest due to the potential synergistic properties that may arise from the combination of two or more precursors. Two such precursors are wood or cellulose fibers and magnetic nanoparticles. These hybrid materials exhibit the inherent properties of the fiber substrate, in particular flexibility and strength, and also the magnetic properties of the surface bonded nanoparticles. Superparamagnetic Iron Oxide Nanoparticles (SPION) covered with a polymer have been used in medical research such as devices for cell isolation, immobilization of enzymes, controlled releasesystems and separation of biological... 

However, it has to be realized that biological templates remain inserted in the final nanoparticles and this is not acceptable for many applications. Nevertheless, some recent examples indicate that such biomimetic materials may be suitable for the design of biotechnological and medical devices [32]. For instance, it was shown that silica gels formed in the presence of p-R5 were excellent host matrices for enzyme encapsulation [33]. In parallel, biopolymer/silica hybrid macro-, micro- and nanocapsules were recently obtained via biomimetic routes and these exhibit promising properties for the design of drug delivery materials (see Section 3.1.1) [34,35],... 

Biomaterials such as proteins/enzymes or DNA display highly selective catalytic and recognition properties. Au nanoparticles or nanorods show electronic, photonic and catalytic properties. The convergence of both types of materials gives rise to Au NP-biomolecule hybrids that represent a very active research area. The combination of properties leads to the appearance of biosensors due to the optical or electrical transduction of biological phenomena. Moreover, multifunctional Au NP-peptide hybrids can be used for targeting nuclear cells where genetic information is stored and could be useful for biomedical applications [146]. 

Fig. 14 Inorganic-organic hybrid CaP/PEG-PAsp/DNA micelle system, a Schematic representation of organic-inorganic hybrid micelle formation, b Biological activities of siRNA incorporated hybrid nanoparticles formed at various PEG-PAsp concentrations. Ratios of GL3 luciferase to RL luciferase -were normalized to cells treated with nanoparticles formed without siRNA. Grey and white bars indicate the ratios of GL3 to RL in the presence of the nanoparticles loading siRNA targeting GL3 luciferase and non-sUencing siRNA (mock) used as a control, respectively. Stars indicate significant difference, with p<0.01 ( ) ( = 6, SEM)...

The chapters in this volume offer overviews of electronic properties, electron transfer and electron-proton coupled charge transfer of biological molecules and macromolecules both in the natural aqueous solution environment and on metallic electrode surfaces, where the electrochemical potential controls biomolecular function. Redox metalloproteins and DNA-based molecules are primary targets, but amino acid and nucleobase building blocks are also addressed. Novel enviromnents where proteins and DNA-based molecules are inserted in metallic nanoparticle hybrids or in situ STM configurations are other focus areas. 

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