Preparation of a thermo- and pH-sensitive nanofibrous scaffold with embedded chitosan-based nanoparticles and its evaluation as a drug carrier
- 362 Downloads
Environmentally sensitive poly(N-isopropylacrylamide) (PNIPAAm) nanofibrous scaffolds loaded with a hydrophilic drug were fabricated via an electrospinning process. First, thermally crosslinkable poly(NIPAAm-co-N-methylolacrylamide) (PNN) was synthesized by redox polymerization below the phase transition temperature of PNIPAAm. The phase transition temperature of the PNN copolymer could be altered from 34 to 40 °C by changing the ratio of N-methylolacrylamide (NMA) to NIPAAm. Subsequently, PNN/chitosan nanofibers were electrospun using ethanol/acetic acid/water as a cosolvent. The PNN/chitosan nanofibers were sensitive to both pH and temperature. The fibrous structure of the soaked PNN/chitosan nanofibers was successfully preserved by the crosslinking of NMA. Furthermore, the chitosan-based nanoparticles (NPs) were introduced into the PNN nanofibers (PNN/NPs) to achieve prolonged drug release. The nanoparticles were observed in the PNN nanofibers by transmission electron microscopy. All of the scaffolds examined had high tensile strengths (1.45 MPa or above) and exhibited no significant cytotoxicity toward human fetal skin fibroblasts. Finally, doxycycline hyclate was used as a model drug. The results illustrated that PNN/NPs nanofibrous scaffolds exhibited continuous drug release behavior for up to 1 week, depending on the pH and temperature.
KeywordsChitosan N-isopropyl acrylamide Nanoparticle Drug release Electrospinning NMA crosslinking
- Jayaraman K, Kotaki M, Zhang Y, Mo X, Ramakrishna S (2004) Recent advances in polymer nanofibers. J Nanosci Nanotechnol 4(1–2):52–65Google Scholar
- Lee WY, Cheng WY, Yeh YC, Lai CH, Hwang SM, Hsiao CW, Huang CW, Chen MC, Sung HW (2011) Magnetically directed self-assembly of electrospun superparamagnetic fibrous bundles to form three-dimensional tissues with a highly ordered architecture. Tissue Eng Part C Methods 17(6):651–661CrossRefGoogle Scholar
- Sahoo S, Ang LT, Goh JC-H, Toh S-L (2010) Growth factor delivery through electrospun nanofibers in scaffolds for tissue engineering applications. J Biomed Mater Res A 93A(4):1539–1550Google Scholar