Polymeric nanopartides

Pinto Reis, C., Neufeld, R.J., Ribeiro, A.J., Veiga, F. and Nanoencapsulation., I. (2006) Methods for preparation of drug loaded polymeric nanopartides. Nanomedicine Nanotechnology, Biology, and Medicine, 2, 8—21. 

Vauthier, Ch. and Bouchemal, K. (2009) Methods for the preparation and manufacture of polymeric nanopartides. Pharmacological Research, 26, 1025-1058. 

Venier-Julienne, M.C. and Benoit, J.P. (1996) Preparation, purification and morphology of polymeric nanopartides as drug carriers. Pharmaceutica Acta Helvetiae, 71, 121—128. 

Christo B. Tsvetanov is full professor of polymer science at the Institute of Polymers, Bulgarian Academy of Sciences and head of the Scientific Council of the Institute of Polymers. A major focus of his research concerns controlled polymerization methods, water-soluble polymers and hydrogels, stimuli-responsive copolymers, and their self-assembly to polymeric nanopartides. He is well known for his contributions to the area of anionic coordination polymerization ofoxiraneandthe role of donor and acceptor additives on the mechanism of anionic polymerization. Since 2004, he has been a corresponding member of the Bulgarian Academy of Sdences. 

Well-defined nanopartides with fimaional groups, such as dendrimers, have been of great interest in a variety of fields over a couple of decades. Star polymers are also expected to serve as nanopartides with unique properties. In order to obtain such polymeric nanopartides, functionalization and predsion synthesis of star polymers would be cmcial. The synthetic strat es for star polymers fall into three categories ... 

Of course, clay particles are not the only nanofiDers used today. Other nanofillers include carbon particles (carbon black and carbon nanotubes), various inorganic oxides (zirconia, titania, silica, etc.), metal nanopartides (gold, silver), and some other, more exotic ones (e.g., polymeric nanopartides such as dendrimers). In general, we can distinguish nanopartides by... 

In their pioneering work, Mackay et al. [26] investigated dispersion of polymeric nanopartides with polymer matrix of the same chemistry (PE, polyethylene PS,... 

Sn02, ZnO, ITO, and BaTiOs, with or without a residual layer, have been successfully created, as wdl as a variety of polymeric nanopartides. 

Srikanfh, H., Hajndl, R., Chirinos, C. and Sanders, J. (2001) Magnetic studies of polymer-coated Fe nanopartides synthesized by microwave plasma polymerization. Applied Physics Letters, 79, 3503-3505. 

Metallic nanopartides were deposited on ceramic and polymeric partides using ultrasound radiation. A few papers report also on the deposition of nanomaterials produced sonochemically on flat surfaces. Our attention will be devoted to spheres. In a typical reaction, commerdally available spheres of ceramic materials or polymers were introduced into a sonication bath and sonicated with the precursor of the metallic nanopartides. In the first report Ramesh et al. [43] employed the Sto-ber method [44] for the preparation of 250 nm silica spheres. These spheres were introduced into a sonication bath containing a decalin solution of Ni(CO)4. The as-deposited amorphous clusters transform to polyciystalline, nanophasic, fee nickel on heating in an inert atmosphere of argon at a temperature of 400 °C. Nitrogen adsorption measurements showed that the amorphous nickel with a high surface area undergoes a loss in surface area on crystallization. 

The use of ultrasound radiation for polymerizing various monomers was reviewed in [la]. Here we will discuss how ultrasound waves have been used successfully been to embed ultrafine metallic partides in a polymeric matrix. The first report was by Wizel and coworkers [57]. They used ultrasound radiation to prepare a composite material made of polymethylacrylate and amorphous iron nanopartides. 

Typically, the processed polymeric nanoparticles are stable in the blood stream and elsewhere in the body [20]. Their degradation and drug release are determined by the chemical degradation rate of the polymer such as poly(lactide) and poly(glycolide). Such nanopartides can be used for site-spedfic intracellular drug delivery if they have targeting moieties on the surface. 

These nanopartides are not dassifled as simple polymeric partides because of their ingredients and formation process. They have been developed very recently and can be considered as a new class of submicronic particles [46]. 

Ham HT, Choi YS, Chee MG et al (2006) Singlewall carbon nanotubes covered with polystyrene nanopartides by in-situ miniemulsion polymerization. J Polym Sd Ptirt A Polym Chem 44 573-584... 

Ham HT, Choi YS, Jeong N et til (2(X)5) Singlewtill caibon nanotubes covered with polypyrrole nanopartides by the miniemulsion polymerization. Polymer 46 6308-6315... 

The self-organization of nanopartides is a powerful tool for the constmction of highly ordered colloidal crystals, biologically active substrates, and optical and electronic devices. Most studies of nano/micropartide assembly have focused on metal or silica partides due to their ideal properties for electronics and optics. One example is the self-assembly of polymeric partides by Wang et whereby the sdf-assembly of PS nanopartides... 

Many of the features discussed above for PEG-stabUized nanopartides containing pDNA also exist with nanopartides carrying other types of nudeic adds. Reviews on polymeric carriers of antisense oligonudeotides and siRNA and polycation-based nanopartide delivery of siRNA " are available. The PEG density and PEG MW are important parameters with short nudeic add delivery " as outlined above with the delivery of plasmids. For example, Bartlett and Davis reported that PEG of MW 5000 Da was necessary to pro-vide steric stabilization with 70 nm nanopartides carrying siRNA. With PEG of this size, the nanopartides had a PEG surface density of 43 pmol cm . 

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