Poly protein delivery

PEG/PBT copolymers are also very good matrix materials for the release of growth factors in tissue engineering. Proteins have been delivered from PEG/PBT microspheres with preservation of protein delivery of complete activity. In the case of protein delivery from PLGA and poly(ortho ester) microspheres, the protein activity was significantly reduced. " ... 

Keyword Adjuvant Biodegradable nanoparticles Poly(y-glutamic acid) Protein delivery Vaccine... 

Poly(esters) (Table 11.2) are the first class of polymers discussed, as they are the most widely investigated of all of the polymer families for oral protein delivery. Poly(esters) used for oral drug delivery have primarily been biodegradable polymers (Figure 11.1). Biodegradation is the primary delivery mechanism for poly(ester) polymers used for protein and peptide delivery. The degradation properties of poly(esters) are dependent on the monomers used to produce the poly(ester). Several poly(esters) are discussed in detail in the following sections. 

Cross-Linked Poly(ethylene Glycol) Networks for Protein Delivery 62... 

Jung T, Breitenbach A, Kissel T (2000) Sulfobutylated poly(vinyl alcohol)-graft-po-ly(lactide-co-glycolide) facilitate the preparation of small negatively charged biodegradable nanospheres for protein delivery. J Control Rel 67 157-169... 

Gao, H., Wang, Y. N. Fan, Y. G., and Ma, J. B. (2006), Conjugates of poly(DL-lactic acid) with ethylenediamino or diethylenetriamino bridged bis(P-cyclodextrin)s and their nanoparticles as protein delivery systems, / Controlled Release, 112,301-311. 

Crotts, G. Park, T.G. Protein delivery from poly(lactic-co-glycolic acid) biodegradable microspheres release kinetics and stability issues. J. of Microencap. 1998,15 (6), 699-713. 

Jung SW, Jeong Yl, Kim YH, Kim SH. Self-assembled polymeric nanoparticles of poly(ethylene glycol) grafted pullulan acetate as a novel drug carrier. Arch Pharmacal Res 2004 27(5) 562-569. Peppas NA. Devices based on intelligent biopolymers for oral protein delivery. Int J Pharm 2004 277(1-2) 11-17. 

G Crotts, TG Park. Protein delivery from poly(lactic-coglycolic acid) biodegradable microspheres Release kinetics and stabihty issues. J Microencapsul 15 699-713, 1998. 

Tang Y, Du Y et al (2009) A thennosensitive chitosan/poly(vinyl alcohol) hydrogel containing hydroxyapatite for protein delivery. J Biomed Mater Res A 91 953-63... 

Oupicky D, Ulbrich K, Rihova, B. Conjugates of semitelechelic poly[N-(2-hydroxypropyl)methacrylamide]with enzymes for protein delivery. J Bioact Biocomp Polymers 1999 14 213-230. 

Bezemer JM, Grijpma DW, Dijkstra PJ, Van Blitterswijk CA, Feijen J. Control of protein delivery from amphiphibc poly (ether ester) multiblock copolymers by varying their water content using emulsification techniques. J Control Release 2000 66 307-320. 

Woo BH, Jiang G, Jo YW, DeLuca PP. Preparation and characterization of a composite PLGA and poly(acryloyl hydro-xyethyl starch) microsphere system for protein delivery. Pharm Res 2001 18 1600-1606. 

LI2 Liu, S.-Q., Yang, Y.-Y., Liu, X.-M., and Tong, Y.-W., Preparation and characterization of temperature-sensitive poly(A-isopropylaciylamide)-Z>-poly(DL-lactide) microspheres for protein delivery, Biomacromolecules, 4, 1784, 2003. 

M. Chiba, J. Hanes, R. Langer, Controlled protein delivery from biodegradable tyrosine-containing poly (anhydride-co-imide) microspheres, Biomaterials 18 (1997) 893-901. 

Zeng, J., Aigner, A., Czubayko, R, Kissel, T., Wendorff, J.H. and Greiner, A. 2005. Poly(vinylalcohol) nanofibers by electrospinning as a protein delivery system and the retardation of enzyme release by additional polymer coatings. Biomacmmolecules 6 ... 

Papadimitriou SA, Achillas DS, Bikiaris DN (2012) Chitosan-g-PEG nanoparticles ionically crosslinked with poly(glutamic acid) and tripolyphosphate as protein delivery systems. Int J Pharm 430 318-327... 

Yeh M-K, Davis SS, Coombes AGA (1996) Improving protein delivery from microparticles using blends of poly(o, l lactide-co-glycolide) and poly(ethylene oxide)-poly(propylene oxide) copolymers. PharmRes 13 1693-1698... 

Major activity in the area of protein delivery from synthetic degradable matrices has focused on the use of aliphatic polyesters, prinicipally owing to their readily manipulated polymer characteristics and the favorable toxicology of their degradation products. However, the development of new polymers and polymeric delivery systems where drug release is predominantly controlled by surface polymer hydrolysis is also desirable. Poly(ortho esters) (POE), of the general structure 3, are an example of this class of synthetic erodible polymers and have been under extensive development for approximately 20 years. 

One particular hydrophobic polymer, EVAc, has been investigated extensively as a matrix system for protein delivery. This polymer is biocompatible, a major consideration because of the interest in developing systems for human health. Other classes of hydrophobic polymers, like silicone elastomers and polyurethanes, may also be useful for controlled protein delivery, although there are fewer examples available in the literature. Nondegradable, hydrophilic polymers, such as poly(2-hydroxyethyl methacrylate) [p(HEMA)], are also biocompatible but usually release proteins over a relatively short period. However, a few examples oflong-term release of peptides and proteins from hydrophilic polymers are available. Longterm release of peptides from devices that employ cross-linked p(HEMA) as rate-limiting barriers has been reported (Davidson et al, 1988). The use of hydrophilic polymers for protein release is discussed in more detail elsewhere in this volume. 

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