Abstract
The aim of this work was to provide an understanding of the interaction occurring between ketoprofen and poly(lacticco-glycodic acid) (PLGA) that leads to polymer plasticization. Experimental glass transition temperature (Tg) values were fitted with the theoretical ones predicted by the Fox and Gordon-Taylor/Kelley-Bueche equations. PLGA films containing different amounts of ketoprofen (KET) were prepared by solvent casting and characterized by scanning electron microscopy, differential scanning calorimetry, and Fourier transform infrared spectroscopy (FTIR). Differential scanning calorimetry evidenced that KET acted as a plasticizer in a similar biphasic way in both end-capped and uncapped PLGA. At KET contents of 20% to 35%, depending on the investigated polymer, the Tg was around 23°C. Higher KET amounts did not lower further the Tg, and the excess of drug was found to crystallize into the polymeric matrix. Experimental Tg's deviated negatively from the predicted ones probably because of hydrogen bonding. The FTIR spectra of the films, loaded with different amounts of KET, showed a shift to higher wavenumbers for the peaks at 1697 and 1655 cm−1 confirming the presence of some interactions, probably hydrogen bonds between the ketoprofen carboxylic group and the PLGA carbonyl groups along the polymer backbone. The hydrogen bonding between KET and PLGA is probably responsible for KET plasticizing effect. KET behaving as a lubricant may disrupt polymer chain-chain interactions, removing additional barriers to bond rotation and chain mobility.
Keywords: Ketoprofen, PLGA, plasticization, glass transition temperature, FTIR, DSC
Full Text
The Full Text of this article is available as a PDF (513.0 KB).
References
- 1.DeLuca PP, Mehta RC, Hausberger AG, Thanoo BC. Biodegradable polyesters for drug and polypeptide delivery. In: El-Nokaly MA, Piatt DM, Charpentier BA, editors. Polymeric Drug Delivery Systems. Washington, DC: American Chemical Society; 1993. pp. 53–79. [Google Scholar]
- 2.Giovagnoli S, Blasi P, Ricci M, Rossi C. Biodegradable microspheres as carriers for native superoxide dismutase and catalase delivery.AAPS Pharm Sci Tech. 2004;5: Article 51. [DOI] [PMC free article] [PubMed]
- 3.Ricci M, Blasi P, Giovagnoli S, Perioli L, Vescovi C, Rossi C. Leucinostatin-A loaded nanospheres: characterization and in vivo toxicity and efficacy evaluation. Int J Pharm. 2004;275:61–72. doi: 10.1016/j.ijpharm.2004.01.030. [DOI] [PubMed] [Google Scholar]
- 4.Jain RA. The manufacturing techniques of various drug loaded biodegradable poly(lactide-co-glycolide) (PLGA) devices. Biomaterials. 2000;21:2475–2490. doi: 10.1016/S0142-9612(00)00115-0. [DOI] [PubMed] [Google Scholar]
- 5.Sperling LH. Introduction to Physical Polymer Science. New York, NY: John Wiley & Sons; 2001. [Google Scholar]
- 6.Okada H, Doken Y, Ogawa Y, Toguchi H. Preparation of three-month injectable microspheres of leuprorelin acetate using biodegradable polymers. Pharm Res. 1994;11:1143–1147. doi: 10.1023/A:1018936815654. [DOI] [PubMed] [Google Scholar]
- 7.Selmin F, D'Souza SS, Blasi P, DeLuca PP. Hydrolytic degradation of PLGA microspheres containing a tertiary amine drug substance [abstract].AAPSJ [serial online]. 2004;S1:Abstract R6176.
- 8.Ricci M, Blasi P, Giovagnoli S, et al. Ketoprofen controlled release from composite microcapsules for cell encapsulation: Effect on post-transplant acute inflammation. J Control Release. 2005;107:395–407. doi: 10.1016/j.jconrel.2005.06.023. [DOI] [PubMed] [Google Scholar]
- 9.Karlsson OJ, Stubbs JM, Karlsson LE, Sundberg DC. Estimating diffusion coefficients for small molecules in polymers and polymer solutions. Polym. 2001;42:4915–4923. doi: 10.1016/S0032-3861(00)00765-5. [DOI] [Google Scholar]
- 10.Di Martino P, Joiris E, Gobetto R, Masic A, Palmieri GF, Martelli S. Ketoprofen-poly(vinylpyrrolidone) physical interaction. J Cryst Growth. 2004;265:302–308. doi: 10.1016/j.jcrysgro.2004.02.023. [DOI] [Google Scholar]
- 11.Fernández-Carballido A, Herrero-Vanrell R, Molina-Martinez IT, Pastoriza P. Biodegradable ibuprofen-loaded PLGA microspheres for intraarticular administration effect of labrafil addition on release in vitro. Int J Pharm. 2004;279:33–41. doi: 10.1016/j.ijpharm.2004.04.003. [DOI] [PubMed] [Google Scholar]
- 12.Kunze C, Freier T, Kramers S, Schmitz KP. Anti-inflammatory prodrugs as plasticizers for biodegradable implant materials based on poly (3-hydroxybutyrate) J Mater Sci. 2002;13:1051–1055. doi: 10.1023/A:1020392606225. [DOI] [PubMed] [Google Scholar]
- 13.Wu C, McGinity JW. Non-traditional plasticizations of polymeric films. Int J Pharm. 1999;177:15–27. doi: 10.1016/S0378-5173(98)00312-3. [DOI] [PubMed] [Google Scholar]
- 14.Tarvainen M, Sutinen R, Somppi M, Paronen P, Poso A. Predicting plasticization efficiency from three-dimensional molecular structure of a polymers plasticizer. Pharm Res. 2001;18:1760–1766. doi: 10.1023/A:1013386900232. [DOI] [PubMed] [Google Scholar]
- 15.Wang Y, Challa P, Epstein DL, Yuan F. Controlled release of ethacrynic acid from poly(lactide-co-glycolide) films for glaucoma treatment. Biomaterials. 2004;25:4279–4285. doi: 10.1016/j.biomaterials.2003.10.075. [DOI] [PubMed] [Google Scholar]
- 16.Wahab MA, Kim I, Ha C-S. Microstructure and properties of polyimide/poly(vinylsilsesquioxane) hybrid composite films. Polym. 2003;44:4705–4713. doi: 10.1016/S0032-3861(03)00429-4. [DOI] [Google Scholar]
- 17.Papkov VS, Nikiforova GG, Nikol'sky VG, Krasotkina IA, Obolonkova ES. Transparent microheterogeneous blends containing a multiblock copolymer and a foreign homopolymers. Polym. 1998;39:631–640. doi: 10.1016/S0032-3861(97)00325-X. [DOI] [Google Scholar]
- 18.Feldstein MM, Shandryuk GA, Plate NA. Relation of glass transition temperature to the hydrogen-bonding degree and energy in poly(N-vinyl pyrrolidone) blends with hydroxyl containing-plasticizers. Part 1. Effects of hydroxyl group number in plasticizer molecule. Polym. 2001;42:971–979. doi: 10.1016/S0032-3861(00)00445-6. [DOI] [Google Scholar]
- 19.Blasi P, D'Souza SS, Selmin F, DeLuca PP. Plasticizing effect of water on poly(lactide-co-glycolide) J Control Release. 2005;108:1–9. doi: 10.1016/j.jconrel.2005.07.009. [DOI] [PubMed] [Google Scholar]
- 20.Matsumoto T, Zografi G. Physical properties of solid molecular dispersions of indomethacin with poly(vinylpyrrolidone) and poly(vinylpyrrolidone-co-vinyl-acetate) in relation to indomethacin crystallization. Pharm Res. 1999;16:1722–1728. doi: 10.1023/A:1018906132279. [DOI] [PubMed] [Google Scholar]
- 21.Garlotta D. A literature review of poly(lactic acid) J Polym Environ. 2001;9:63–84. doi: 10.1023/A:1020200822435. [DOI] [Google Scholar]
- 22.Kister G, Cassanas G, Vert M. Effect of morphology, conformation and configuration on the IR and Raman spectra of various poly(lactic acid)s. Polym. 1998;39:267–273. doi: 10.1016/S0032-3861(97)00229-2. [DOI] [Google Scholar]
- 23.Agarwal M, Koelling KW, Chalmers JJ. Characterization of the degradation of polylactic acid polymer in a solid substrate environment. Biotechnol Prog. 1998;14:517–526. doi: 10.1021/bp980015p. [DOI] [PubMed] [Google Scholar]
- 24.Sancin P, Caputo O, Cavallari C, et al. Effects of ultrasound-assisted compaction on ketoprofen/Eudragit S100 mixtures. Eur J Pharm Sci. 1999;7:207–213. doi: 10.1016/S0928-0987(98)00022-0. [DOI] [PubMed] [Google Scholar]
- 25.Mura P, Bettinetti GP, Manderioli A, Faucci MT, Bramanti G, Sorrenti M. Interactions of ketoprofen and ibuprofen with β-cyclodextrins in solution and in the solid state. Int J Pharm. 1998;166:189–203. doi: 10.1016/S0378-5173(98)00035-0. [DOI] [Google Scholar]
- 26.Briard PP, Rossi JC. Kétoprofène. Acta Crystallogr. 1990;C46:1036–1038. [Google Scholar]
- 27.Gupta MK, Vanwert A, Bogner RH. Formation of physically stable amorphous drugs by milling with neusilin. J Pharm Sci. 2003;92:536–550. doi: 10.1002/jps.10308. [DOI] [PubMed] [Google Scholar]
- 28.Taylor LS, Zografi G. Spectroscopic characterization of interaction between PVP and indomethacin in amorphous molecular dispersions. Pharm Res. 1997;14:1691–1698. doi: 10.1023/A:1012167410376. [DOI] [PubMed] [Google Scholar]
- 29.Vueba ML, Pina ME, Veiga F, Sousa JJ, Batista de Carvalho LAE. Conformational study of ketoprofen by combined DFT calculations and Raman spectroscopy. Int J Pharm. 2006;307:56–65. doi: 10.1016/j.ijpharm.2005.09.019. [DOI] [PubMed] [Google Scholar]
- 30.Schachter DM, Xiong J, Tirol GC. Solid state NMR perspective of drug-polymer solid solutions: a model system based on poly(ethylene oxide) Int J Pharm. 2004;281:89–101. doi: 10.1016/j.ijpharm.2004.05.024. [DOI] [PubMed] [Google Scholar]
- 31.Hodge RM, Bastow TJ, Edward GH, Simon GP, Hill AJ. Free volume and the mechanisms of plasticization in water-swollen poly(vinyl alcohol) Macromolecules. 1996;29:8137–8143. doi: 10.1021/ma951073j. [DOI] [Google Scholar]
- 32.Anderson SL, Grulke EA, DeLassus PT, Smith PB, Kocher CV, Landes BG. A model for antiplasticization in polystyrene. Macromolecules. 1995;28:2944–2954. doi: 10.1021/ma00112a047. [DOI] [Google Scholar]
- 33.Kobayashi Y, Zheng W, Meyer EF, McGervey JD, Jamieson AM, Simha R. Free volume and physical aging of poly(vinyl acetate) studied by positron annihilation. Macromolecules. 1989;22:2302–2306. doi: 10.1021/ma00195a052. [DOI] [Google Scholar]