Cartilage delivery

Lucas, P. A., Laurencin, C., Syftestad, G. T., Domb, A., Goldberg, V. M., Caplan, A. I., and Langer, R., Ectopic induction of cartilage and bone by water-soluble proteins from bovine bone using a polyanhydride delivery vehicle, J. Control. Rel. In Press. 

Recently, water-soluble protein fractions, isolated from extracts of bone matrix, were incorporated into a collagen matrix and shown to induce bone (67,68) and cartilage formation both in vitro and in vivo (69,70). In the latter studies, in the absence of the collajgen delivery system, the proteins were incapable of inducing cartilage formation in vivo when implanted intramuscularly into mice. The success of this approach appears to depend on delivering the active agents at an effective dose over an extended time period. 

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]. 

Polysiloxanes are widely employed as biomaterials. Artificial skin can be fabricated from a bilayer fabricated from a cross-linked mixture of bovine hide, collagen, and chondroitin sulfate derived from shark cartilage with a thin top layer of polysiloxane. The polysiloxane acts as a moisture and oxygen-permeable support and protects the lower layer from the outer world. A number of drug delivery systems use polysiloxanes because of the flexibility and porous nature of the material. 

Poly(esters) Poly(glycolic acid) (PGA) Poly(lactic acid) (PLA) Poly(caprolactone) (PCL) Poly(lactic-co-glycolic) (PLGA) Cartilage, bone, muscle, nerve, blood vessel, valves, bladder, liver, cardiac tissue, drug delivery, sutures [11,12]... 

Other biomedical applications of polymers include sustained and controlled drug delivery formulations for implantation, transdermal and trans-cornealuses, intrauterine devices, etc. (6, 7). Major developments have been reported recently on the use of biomaterials for skin replacement (8), reconstruction of vocal cords (9), ophthalmic applications such as therapeutic contact lenses, artificial corneas, intraocular lenses, and vitreous implants (10), craniofacial, maxillofacial, and related replacements in reconstructive surgery (I), and neurostimulating and other electrical-stimulating electrodes (I). Orthopedic applications include artificial tendons (II), prostheses, long bone repair, and articular cartilage replacement (I). Finally, dental materials and implants (12,13) are also often considered as biomaterials. 

Park et al. [102] designed an injectable cell delivery chitosan-Pluronic hydrogel for articular cartilage regeneration. The chitosan-Pluronic solution underwent a sol-gel transition at around 25 °C. The chitosan-Pluronic hydrogel showed effective chondrocyte proliferation and promoted extracellular matrix expression compared with alginate hydrogel. 

This review firstly focuses on modification of the chitosan molecule to obtain desired properties and functions. The most important material forms (porous scaffolds, hydrogels, and rods) and delivery vectors fabricated from chitosan and its derivatives will be introduced. Particularly, the interaction and modulation of stem cell behavior by chitosan will be discussed. Finally, the applications of chitosan-based materials for repair and regeneration of various tissues and organs such as skin, cartilage, and bone will be summarized. 

H. Hyaluronan as a Delivery Vehicle for Cartilage and Bone Repair Applications... 

Hemostats wound dressings cartilage repair soft-tissue augmentation Drug and biologically active macromolecule delivery soft- and hard-tissue augmentation... 

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