Poly L-Lactic Acid

Poly(L-lactic acid) EcoPLA, NatureWorks Dow-Cargill Environmental, biomedical Lactic acid from corn starch fermentation... 

Poly(L-lactic acid) Lacty Shimadzu Environmental, biomedical b... 

PLA degradation, 43 Planar polymer, synthesis of, 505 PLLA. See Poly(L-lactic acid) (PLLA) PMDA. See Pyromellitic dianhydride (PMDA)... 

Polylactides, 18 Poly lactones, 18, 43 Poly(L-lactic acid) (PLLA), 22, 41, 42 preparation of, 99-100 Polymer age, 1 Polymer architecture, 6-9 Polymer chains, nonmesogenic units in, 52 Polymer Chemistry (Stevens), 5 Polymeric chiral catalysts, 473-474 Polymeric materials, history of, 1-2 Polymeric MDI (PMDI), 201, 210, 238 Polymerizations. See also Copolymerization Depolymerization Polyesterification Polymers Prepolymerization Repolymerization Ring-opening polymerization Solid-state polymerization Solution polymerization Solvent-free polymerization Step-grown polymerization processes Vapor-phase deposition polymerization acid chloride, 155-157 ADMET, 4, 10, 431-461 anionic, 149, 174, 177-178 batch, 167 bulk, 166, 331 chain-growth, 4 continuous, 167, 548 coupling, 467 Friedel-Crafts, 332-334 Hoechst, 548 hydrolytic, 150-153 influence of water content on, 151-152, 154... 

The earliest reports of controlled release steroids were those of Jackanicz (63), Yolles (64), Anderson (65), and Wise (66). Most of those early studies were based on poly[ (L+)-lactic acid). Implants and granular particles were fabricated with progesterone, norgestrel, and norethisterone. In vivo urinary excretion studies were conducted on [I Cjprogesterone beads (64). The reported results were somewhat questionable as only 20% of the original implanted drug could be accounted for. 

Various antimalarial drugs have been studied in biodegradable delivery systems. Wise (89) reported the use of a lactide/glycolide copolymer and also poly(L-lactic acid) for release of drugs such as quinazoline and sulfadiazine. Although in vitro data and experiments in mice were somewhat encouraging, these early formulations failed to reach significant clinical status. 

Christei, P., Chabot, F., and Vert, M., In vivo fate of bioresorbable bone plates of long-lasting poly(L-lactic acid), Proc. 2nd World Congress on Biomaterial, 279, 1984. 

Low molecular weight. For poly(L-lactic acid) of high molecular weight [MW = 500,000], the tensile strength is about 500 kg/cm and the tensile modulus is about 25,000 kg/cm. ... 

T. O. Park, S. Cohen, and R. Langer, Controlled protein release from polyethyleneimine-coated poly(l-lactic acid)/pluronic blend matrices, Pharm. Res, 9, 37 (1992). 

Zhang, R. and Ma, P.X. (1999) Porous poly(L-lactic acid)/apatite composites created by biomimetic process. Journal of Biomedical Materials Research, 45, 285-293. 

Liggins RT, Burt HM (2001) Paclitaxel loaded poly(L-lactic acid) microspheres properties of microspheres made with low molecular weight polymers. Int J Pharm 222 19-33... 

M. Tanaka and R.J. Young, Molecular orientation distributions in uniaxiaUy oriented poly(L-lactic acid) films determined by polarized Raman spectroscopy. Macromolecules, 39, 3312-3321 (2006). 

Tamai H, Igaki K, Tsuji T, et al. A biodegradable poly-L-lactic acid coronary stent in porcine coronary artery. J Interv Cardiol 1999 12 443-450. 

Fig. 2. Formation of polyfglycolic acid) and poly(L-lactic acid) by ring-opening polymerization of glycolide (R = H) and L-lactide (R = CH3) respectively...

Fig. 4a, b. Scanning electron photomicrographs of amorphous poly(L-lactic acid) foams a 92% porosity and 30 pm median pore diameter b and 91% porosity and 94 pm median pore diameter. Prepared by a solvent-casting and particulate-leaching method [32] using 90 wt% sieved sodium chloride particles of size range between 0-53 pm and 106-150 pm, respectively... 

Masinde, L. and Hickey, A.J. (1993). Aerosolized aqueous suspensions of poly(L- lactic acid) microspheres. Int. J. Pharmaceut., 100, 123-131. 

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