Tissue-based scaffolds

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]. 

Cloyd JM et al (2007) Material properties in unconfined compression of human nucleus pulposus, injectable hyaluronic acid-based hydrogels and tissue engineering scaffolds. Eur Spine J 16(11) 1892-1898... 

Torres, F. G., Boccaccini, A. R., Troncoso, O. P. (2006). Microwave processing of starch-based porous structures for tissue engineering scaffolds. J. Appl. Poly. ScL, 103(2), 1332-1339. 

Lyons, F. G., Al-Munajjed, A. A., Kieran, S. M., Toner, M. E., Murphy, . M., Duffy, G. P., and O Brien, F. J. (2010). The healing of bony defects by cell-free collagen-based scaffolds compared to stem cell-seeded tissue engineered constructs. Biomaterials 31, 9232-9245. 

Moffat KL et al (2009) Novel nanofiber-based scaffold for rotator cuff repair and augmentation. Tissue Eng A 15( 1) 115—126... 

Examples of biomaterials include sodium hyaluronate, a naturally occurring biopol3nner used to reduce the incidence of postsurgical adhesions polymer-based materials for controlled-drug release and tissue engineered scaffolds to... 

HA-based nanofibrous membranes have been extremely attractive as bio-mimetic tissue engineering scaffolds and wound healing materials. In order to mimic the architecture of the natural ECM using electrospinning, a thiolated-HA derivative was synthesized and electrospun to form nanofibrous matrices [137]. 

RinM K, Dutta J, Dutta PK (2007) Chitosan based scaffolds for tissue engineering applications. Asian Chitin J 3 69-78... 

Rinki K, Dutta PK (2010) Chitosan based scaffolds by lyophilization and sc. CO2 assisted methods for tissue engineering applications a benign green chemistry approach. J Macromol Sci Pure Appl Chem A47 429 34... 

Chitosan and its derivatives are also effective in regenerating the wounded skin tissue. A chitosan/collagen-based scaffold combining dermal stem cells and hair follicle epidermal stem cells was reported to provide a suitable substrate for the tridimensional growth of skin stem cells (40). An active laminin peptide-conjugated chitosan membrane has recently been demonstrated as a suitable scaffold material for delivering keratinocytes to the wound bed (41). 

Yilgor, R Tuzlakoglu, K. Reis, R. L. Hasrrci, N. and Hasirci, V Incorporation of a sequential BMP-2/BMP-7 delivery system into chitosan-based scaffolds for bone tissue engineering. Biomaterials. 2009, 30(21), 3551-3559. 

FIGURE 46.2 A functional surface based strategy to probe cell-ligand interactions — an iterative tissue engineering scaffold design approach. (Reproduced from Song, J. et al., /. Mater. Chem., 2004,14 2643-8. With permission.)... 

Abstract Polyhydroxyalkanoate (PHA) is a plastic-like material synthesized by many bacteria. PHA serves as an energy and carbon storage componnd for the bacteria. PHA can be extracted and purified from the bacterial cells and the resulting product resembles some commodity plastics such as polypropylene. Because PHA is a microbial product, there are natural enzymes that can degrade and decompose PHA. Therefore, PHA is an attractive material that can be developed as a bio-based and biodegradable plastic. In addition, PHA is also known to be biocompatible and can be used in medical devices and also as bioresorbable tissue engineering scaffolds. In this chapter, a brief introduction about PHA and the fermentation feedstock for its production are given. 

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