Biodegradable polymers experimental

For the development of drug delivery systems it is of fundamental importance to achieve the co-precipitation of drugs and biodegradable polymers. The supersaturation working conditions of S AS allow, in many cases, fast and simultaneous precipitation of both polymer and drugs, so that the drugs can be trapped into the polymer matrix. A list of the coprecipitation experimental results is reported in Table 9.9-5. 

Olivi, A. Ewend, M.G. Utsuki, T. Tyler, B. Domb, A.J. Brat, D.J. Brem, H. Interstitial delivery of carboplatin via biodegradable polymers is effective against experimental glioma in the rat. Cancer Chemother. Pharmacol. 1996, 39, 90-96. 

Sakurai E, Matsuda Y, Ozeki H, Kunou N, Nakajima K, Ogura Y. Scleral plug of biodegradable polymers containing ganciclovir for experimental cytomegalovirus retinitis. Invest Ophthalmol Vis Sci 2001 42 2043-2048. 

Keller N, Jamieson L, Olejnik O, et al. Efficacy of intravitreal dexamethasone in experimental uveitis effect of drug delivery in a biodegradable polymer. Invest Ophthalmol Vis Sci 1986 27 248 [ARVO abstract]. 

Strasser, J.F., et al. Distribution of l,3-bis(2-chloroethyl)-l-nitrosourea (BCNU) and tracers in the rabbit brain following interstitial delivery by biodegradable polymer implants. Journal of Pharmacology and Experimental Therapeutics, 1995, 275(3), 1647-1655. 

Walter, K.A., et al., Interstitial taxol delivered from a biodegradable polymer implant against experimental malignant glioma. Cancer Research, 1994, 54, 2207-2212. 

Hanes J, Sills A, Zhao Z, Suh KW, Tyler B, DiMeco F, Brat DJ, Choti MA, Leong KW, Pardoll DM, Brem H. Controlled local dehveiy of interleukin-2 by biodegradable polymers protects animals from experimental brain tumors and liver tumors. Pharm Res 2001 18 899—906. 

Rhines LD, DiMeco F, Lawson HC, Tyler BM, Hanes J, Olivi A, Brem H. Local immunotherapy with interleukin-2 delivered from biodegradable polymer microspheres combined with interstitial chemotherapy A novel treatment for experimental malignant glioma. Neurosurgery 2003 52 1-8. 

Williams JA, Dillehay LE, Tabassi K, Sipos E, Fahlman C, Brem H. Implantable biodegradable polymers for lUdR radiosensitization of experimental human malignant glioma. J Neurooncol 1997 32 181-192. 

Poly(bulylene succinate) (PBS) is another biodegradable polymer which is not commonly blended with polyolefins. However, Yang et al. [94] investigated the eflect of PBS content, extrusion rate, and extensional strain rate on the melt strength and extensional viscosity of LDPE/PBS blends using a melt-spinning technique, and developed extensional master curves. Based on both the extensional master curve and a neural network method, they compared the predicted extensional viscosities with the experimental data of the LDPE/PBS blends. 

All polymer fibers in vitro (controls and experimentals) began to dissolve by 4 weeks, which is comparable to their anticipated time for dissolution. When evaluating implants from in vivo experiments, on gross examination, the experimental biodegradable polymer fibers were progressively replaced by cartilage, until only cartilage with very... 

Gangadharam PRJ, Kailasam S, Srinivasan S et al (1994) Experimental chemotherapy of tuberculosis using single dose treatment with isoniazid in biodegradable polymers. Br J Antimicrobial Chemotherapy 33 265-271... 

Optically active lactones are valuable building blocks in organic synthesis (4) and in the preparation of optically active biodegradable polymers (7,5). Several chemical methods for producing these compounds and their corresponding polymers have been explored (6) but unfortunately all of these methods are either experimentally cumbersome or afford the lactones with only modest enantioselectivities. Examples of chemically prepared optically active polyesters include poly(a-phenyl-P-propiolactone) (7), poly(a-ethy(-a-phenyl-P -propiolactone) (S, 9), poly(a-methyl-a-ethyl-P-propiolactone) (70) and poly(lactic acid) (77, 72). Use of enantioselective polymerization catalysts to carry out stereoelective polymerizations of racemic lactones has produced mixed results. For example, stereoelective polymerization of [/ ,S]- P-methyl-P-propiolactone with a catalyst from Zn ( 2115)2 and [7 ]-(-)-3,3-dimethyl-l,2-butanediol showed only a small enantiomeric enrichment in the final polymer (75). Stereoselective copolymerizations of racemic (LL/DD monomers) and meso (LD monomer) lactides using chiral catalyst that gives heterotactic and syndiotactic PLA, respectively have also been studied (77). 

E. Sakurai, M. Nozaki, K. Okabe, N. Kunou, H. Kimura, and Y. Ogura, Scleral plug of biodegradable polymers containing tacroHmus (FK506) for experimental uveitis. Invest. Ophthalmol. Vis. ScL, 44 (11), 4845-4852,2003. 

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