Nanostructured Biodegradable Polymers

The nanoparticles propose advantages of drug targeting by modified body distribution [41] as well as the enhancement of the cellular uptake [42], which benefits from reduction of undesired toxic side effects of the drugs [43]. NPs can be transported via the natural circulation system to different body sites, thanks to their easy accessibility in the body [44]. 

Nanoparticles can be prepared from a variety of materials such as polysaccharides, protein and synthetic polymers. The choice of materials depends on different factors [26,45]  

Drug transport using polymeric nanoparticles, in absorptive epithelial cells, takes place mainly through the vesicular endocytic pathways, and can be mediated by interactions between NP-cell membrane [46]. Rescignano et al. used fluorescently labeled NPs to provide a rapid, simple, and sensitive means to quantify cell-associated NPs by 

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The aim of this chapter is to put in evidence the evolution of nanostructured biodegradable polymer approaches in pharmaceutical and biomedical applications. 

Biodegradable Polymer-based Nanocomposites Nanostructure Control and Nanocomposite Foaming with the Aim of Producing Nano-cellular Plastics... 

In the last few years there have been new creative methods of preparation of novel hydrophilic polymers and hydrogels that may represent the future in drug delivery applications. The focus in these studies has been the development of polymeric structures with precise molecular architectures. Stupp et al. (1997) synthesized self-assembled triblock copolymer, nanostructures that may have very promising applications in controlled drug delivery. Novel biodegradable polymers, such as polyrotaxanes, have been developed that have particularly exciting molecular assemblies for drug delivery (Ooya and Yui, 1997). 

Lu, Y., et al. (2005), Shaping biodegradable polymers as nanostructures Fabrication and applications, Drug Discov. Today Techno., 2(1), 97-102. 

Blending and compositing have been successfully used in starch-based materials. Starch was initially used a fillers blended with various polymers, especially with polyolefin. Blending starch with biodegradable polymers has attracted more and more attention. The interest in new nanoscale fillers has rapidly grown since it was discovered that a nanostructure could be built from a polymer and a layered nanoclay. These new nanocomposites show dramatic improvement in mechanical properties with low filler content. Cellulose is the major substance obtained from vegetable fibers, and applications for cellulose fiber-reinforced polymers have again come to the forefront with the focus on renewable feedstocks. Hydrophilic cellulose fibers are very compatible with most natural polymers. 

Sitharaman, B., Shi, X. F., Tran, L. A., Spicer, P. P., Rusakova, I., Wilson, L. J. Mikos, A. G. (2007) Injectable in situ cross-linkable nanocomposites of biodegradable polymers and carbon nanostructures for bone tissue engineering. Journal of Biomaterials Science - Polymer Edition, 18, 655-671. 

Mclnnes SJ, Irani Y, Williams KA, Voelcker NH (2012) Controlled drug delivery from composites of nanostructured porous silicon and poly(L-lactide). Nanomedicine 7(7) 995-1016 Park JH, Ye M, Park K (2005) Biodegradable polymers for microencapsulation of drugs. Molecules 10 146-161... 

The aim of the present study is to develop new methods for the fabrication of nanoporous biopolymer materials by combining recent advances in the field of elaboration of nanostructured inorganic materials and biodegradable polymer. For this purpose we synthesized poly(DL-lactide) (PDLLA) copolymerized with poly(ethylene oxide) (PEO). 

The possibility to combine different reinforcement phases in a polymer matrix was also recently considered in order to obtain multifunctional systems with increased mechanical and thermal properties providing also an antimicrobial response. In a recently accepted paper [160] Fortunati et al. demonstrated the high potential benefits offered by nanotechnology in the development of tailor-made nanobiocomposites with specific applications by the combination of two different synthesized nanostructures inorganic nanoparticles and cellulose nanocrystals in a biodegradable polymer matrix. 

Biodegradable polymers Brownian motion Cellulose fibers Nanostructured materials Polymer nanocomposites... 

Currently, there is abundant literature on the use of nanocomposites systems comprising nanoscale ceramics and biodegradable polymers as bone snbstitutes. The pnrpose of this section is to focns specifically on the most advanced nanostructured materials and systems (ie, the last generation of scaffolds, according to the scheme of Fig. 15.2), developed for bone regeneration and healing functions. When possible, the role of... 

Because CDs are nontoxic, biodegradable, and bioabsorbable, they may be used in medical applications, as well as providing for the fabrication of more environmentally responsible polymer materials. In this report we have summarized almost exclusively our own recent studies employing the cyclic starch derivatives called cyclodextrins to both nanostructure and functionalize polymer materials. Lest the reader gets the erroneous impression that our studies have been carried out in isolation, we refer to a recent review [120], and a summary [121], describing related... 

Chin Han Chan, PhD, is an associate professor at the Faculty of Applied Sciences, Universiti Teknologi MARA [MARA University of Technology) in Selangor, Malaysia. She has received many research grants, has published many articles in professional journals, has published chapters in books, and has presented at many professional conferences. Her field of interest includes epoxidized natural rubber-based nanostructured blends, thermoplastic elastomer, biodegradable polyester/polyether blends, and solid polymer electrolytes. 

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