| Autor: |
de Araújo, Márcia Valéria Gaspar, Vieira, João Victor Francisco, da Silva, Thiago Alessandre, Kubota, Tatiana, Barboza, Fernanda Malaquias, Farago, Paulo Vitor, Zawadzki, Sônia Faria |
| Zdroj: |
Macromolecular Symposia; Sep2012, Vol. 319 Issue 1, p179-190, 12p |
| Abstrakt: |
Summary: Polymers derived from cyclodextrins show several biomedical applications. In this paper, six cross-linked polyurethane networks based on β-cyclodextrin ( βCD) or hydroxypropyl- β-cyclodextrin (HP βCD) and polyethylene glycols (PEG 400, PEG 1500 or PEG 4000) were synthesized by the usual two-step polymerization method. The polymers were characterized by Fourier-transformed infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA) and X-ray diffraction (XRD). The inclusion capacity was evaluated by the discoloration method of a phenolphthalein solution. In order to explore their potential use as controlled drug delivery systems, dissolution profiles and release behavior of inclusion complexes between PUR/TDI/ βCD/PEG4000 or PUR/TDI/HP βCD/PEG1500 and nifedipine (NIF) were investigated. FTIR assignments confirmed the formation of urethane linkages. XRD patterns revealed that the crystallinity decreased mainly due to the crosslinking process. TGA showed three stages of mass loss attributed to water loss, cleavage of urethane bonds and volatilization of decomposition products. The inclusion capacity of cyclodextrins cross-linked with polyurethane was suitably maintained. Dissolution profiles demonstrated that the inclusion complexes PUR/TDI/ βCD/PEG4000-NIF and PUR/TDI/HP βCD/PEG1500-NIF are feasible systems for controlling drug release, showing a biexponential release behavior. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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