Preparation and cellular compatibility of optical-controlled thermo-responsive poly(N-isopropyl acrylamide)

• Main Authors: Geng-Ming Zhang, 張耿銘
• Other Authors: Trong-ming Don
• Format: Others
• Language: zh-TW
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/97711886212108783155

碩士 === 淡江大學 === 化學工程與材料工程學系碩士班 === 99 === In this study, 4,4''-azobis(4-cyanovaleric acid) (ACPA) was used to initiate polymerization of N-isopropyl acrylamide (NIPAAm) monomer in ethanol at 70oC to form carboxyl-terminated poly(N-isopropyl acrylamide) telechelic polymer (PNIPAAm-COOH). Subsequently, N-(3-dimethylaminopropyl)-N''-ethylcarbo- diimide hydrochloride and 2-mercapto-ethylamine hydrochloride (cysteamine hydrochloride) were chosen to modify the PNIPAAm-COOH to prepare thiol-end-capped poly(N-isopropyl acrylamide) (PNIPAAm-SH) , SH-functionalized content of 28.32 μmole/g polymer, instead of 11.4 %. In addition, nano-sized gold rod (GNR) was synthesized via the well-known seed-mediated method. The synthesized GNR was very uniform and had a dimension of 37.23(±0.91) nm in length and 11.15(±0.29) nm in width, thus having an aspect ratio (AR) of 3.34. Finally, PNIPAAm-SH with different amounts was added to the GNR solution to produce PNIPAAm-g-GNR composite. It was found the PNIPAAm-g-GNR solution prepared by grafting 2.5 μmol PNIPAAm-SH onto 4.64 nM of GNR solution at 30 oC had a superior stability. STEM results confirmed that the thiol group bonded onto the surface of gold nanorod, and the TEM image showed that the gold nanorod was protected by multi-layers of PNIPAAm chains. The PNIPAAm-g-GNR solution was tested for the near-IR irradiation-induced thermo-responsibility and cell compatibility. The results showed that all PNIPAAm-COOH, PNIPAAm-SH and PNIPAAm-g-GNR had the same LSCT at about 35 oC. Because of the surface plasmon effect of gold nanorod, the irradiation of near-IR at 808 nm for 15 minutes could induce the temperature rise from 27 oC to 45 oC. The thermo-responsibility was also reversible during five test cycles. Moreover, the PNIPAAm protection layer could decrease the cytotoxicity of the gold nanorod. The Cell Viability of 1.07 % from the previous increase to 89.0 %.