Regenerative medicine natural polymers

Polyesters of naturally occurring a-hydroxy acids, including PGA, PLA, and PLGA, are widely used in regenerative medicine. These polymers have gained FDA approval for human use in a variety of... 

Electrospinning techniques enable the production of continuous fibers with dimensions on the scale of nanometers from a wide range of natural and synthetic polymers [135]. The number of recent studies regarding electrospun polysaccharides and their derivatives, which are potentially useful for regenerative medicine, is dramatically increasing. 

Due to their availability and controllable degradation rate, synthetic biomaterials are also considered to be potential candidates in tissue engineering and regenerative medicine. Compared to natural polymers, synthetic polymers can easily be tailored into any form snitable for tissue engineering applications. Such materials should provide a three-dimensional (3D) structure that not only plays a supportive role for the tissue but also interacts with cells to control their... 

This chapter reviews major natural and synthetic polymers, based on their diverse apphcations in tissue engineering/regenerative medicine. It also gives an outline of the advantages of biodegradable polymers over conventionally used allografts and autografts. 

NATURAL POLYMERS IN TISSUE ENGINEERING AND REGENERATIVE MEDICINE... 

The major natural polymers currently in use are proteins and polysaccharides. Due to diverse physical and chemical properties, natural polymers play a key role in tissue engineering and regenerative medicine. In the following section, we describe some frequently used protein polymers for tissue engineering and regenerative medicine applications. 

This textbook will allow an easy access into the field especially for advanced and graduate students as well as experienced researchers in natural sciences and biomedical specialists entering the field or being interested in and working at the interface between polymeric materials and biomedicine. Target study areas are bioengineering, biomaterials science, biomedical science, chemistry biophysics, polymer science, and regenerative medicine. 

Polymers used as biomaterials can be natural, synthetic or hybrid. With the growing field of regenerative medicine and medical devices, polymers dominate the soft tissue engineering and drug delivery industry and are gradually replacing metals and ceramics in the hard tissue engineering field as well. 

In regenerative medicine, there are various different materials suitable as implantable scaffolds. These can be fabricated from natural or synthetic materials. Common examples are polysaccharides (eg, chitosan), or polyesters (eg, poly e-caprolactone), for natural and synthetic polymers, respectively. However, they are both capable of degradation (either enzyme mediated, or hydrolysis) in vivo (Bassi et al., 2011 Cunha-Reis et al., 2007). Often, polyesters are used as implantable biodegradable biomaterials, as they have controllable degradation and mechanical properties through formation of block copolymers. Where degradation occurs, the scaffolds... 

Natural polymers have been extensively used for various TE applications (mainly bone, skin, and cartilage blood vessels hgaments) (Malafaya et al., 2007). The main advantages of this class of materials are their excellent biocompatibility and that some of them are major components of the ECM in natural tissues. Hence, being the natural substrate for cell adhesion, proliferation, and differentiation, they represent the ideal cell delivery vehicle for regenerative medicine applications. However, being... 

Table 19.1 Natural and synthetic bioresorbable polymers used in the field of cardiovascular regenerative medicine...

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