Tissue engineering scaffolds common polymers

PGA was one of the very first degradable polymers ever investigated for biomedical use. PGA found favor as a degradable suture, and has been actively used since 1970 [45 -7]. Because PGA is poorly soluble in many common solvents, limited research has been conducted with PGA-based drug delivery devices. Instead, most recent research has focused on short-term tissue engineering scaffolds. PGA is often fabricated into a mesh network and has been used as a scaffold for bone [48-51], cartilage [52-54], tendon [55, 56], and tooth [57]. 

Abstract Synthetic polymers and biopolymers are extensively used within the field of tissue engineering. Some common examples of these materials include polylactic acid, polyglycolic acid, collagen, elastin, and various forms of polysaccharides. In terms of application, these materials are primarily used in the construction of scaffolds that aid in the local delivery of cells and growth factors, and in many cases fulfill a mechanical role in supporting physiologic loads that would otherwise be supported by a healthy tissue. In this review we will examine the development of scaffolds derived from biopolymers and their use with various cell types in the context of tissue engineering the nucleus pulposus of the intervertebral disc. 

Hydrogels are one of the most common tissue engineering scaffolds. In its most basic form, a hydrogel consists of a solution of hydrophilic polymer, suspended in water, that forms a gel on cross-linking. Cross-linking may be induced by a radical initiator, usually photo- or heat activated, which cross-links linear or branched polymers. As with electrospinning, there are many polymers and polymer blends that have been made into hydrogels (Li et al., 2015 Lin and Li, 2014 Sun et al., 2014). 

Polymers (macromolecules) are the primary materials for various tissue engineering scaffolds such as skin, cartilage, bone etc. Limited number of inorganic materials is used in bone and mineralized tissue engineering applications. In this chapter, the most commonly used polymers in tissue engineering are reviewed. 

Commonly used polymers as tissue engineering scaffolds... 

For tissue engineering applications, both synthetic and natural polymers need to be processed into scaffolds with suitable structure and chemical properties that match the reproduced tissue. The following part will introduce some commonly used methods of fabricating tissue engineered scaffolds. 

Selection of a tissue engineering substrate includes a choice between absorbable and nonabsorbable material, as well as a choice between synthetic and naturally derived materials. The most common synthetic polymers used for fibrous meshes and porous scaffolds include polyesters such as polylactide and polyglycolide and their copolymers, polycaprolactone, and polyethylene glycol. Synthetic polymers have advantages over natural polymers in select instances, such as the following i... 

Synthetic polymers commonly used in numerous biomedical devices offer the distinct advantage of high level of control over the chemical properties of the polymer. As a scaffold for adipose tissue engineering, polylactic acid, polyglycolic acid, and copolymers incorporating both have been widely investigated due to their ability to degrade over... 

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