奈米金具有多項的優點,例如容易製造、具有光學特性、易與生物分子相結合與良好的生物相容性等,因此奈米金的技術及應用也以驚人的速度成長,舉凡電子、半導體、觸媒、染料、生醫等領域中,都可以發現它的蹤跡。在本研究中,利用檸檬酸鈉還原金奈米粒子,將羧基硫醇之11-Mercaptoundecanoic acid (MUA) 或是烷基硫醇之1-Denanethiol (DCT) 修飾後的金奈米粒子,利用氧電漿使Au(mua)或Au(DCT)表面產生自由基,因氧電漿可快速地使高分子形成自由基,然後快速地與氧自由基或氧分子反應,迅速氧化材料表面。並利用UV光將異丙基丙烯醯胺 (N-isopropyl acrylamide) 高分子單體聚合接枝於金奈米粒子上,使金奈米粒子表面接枝固定具有感溫性的聚異丙基丙烯醯胺高分子。利用XPS可以證明硫醇基有修飾於奈米金的表面,並利用石英震盪天平 (QCM) 量測奈米金的濃度,由頻率變換得之重量,經由換算即可得知奈米金溶液濃度。由UV-vis.得知Au(mua)與Au(DCT)經由氧電漿表面處理後,能成功接上PNIPAAm高分子,且粒子具有溫度感應性。初步藉由細胞培養得知,Au(mua)粒子對脂肪細胞有較好的促進生長效果;Au(DCT)粒子對纖維母細胞有較好的促進生長效果。
Gold is most extensively studied because of its unique optics property, simple preparation, and high stability. Gold nanoparticles (Nano-Au) were modified with different thiol bases to create hydrophilic or hydrophobic functional groups on the surface of gold nanoparticle, and then thermosensitive poly N-isopropyl acrylamide (PNIPAAm) polymer was grafted. Nano-Au were prepared by the reduction reaction of trisodium citrate with hydrogen tetrachloroaurate (III) tetrahydrate (chloroauric acid) and modified with 11-mercaptoundecanoic acid (MUA) or 1-Decanethiol by the self-assembly monolayer (SAM). The oxygen plasma pretreatment on the nano-Au particles creates peroxide groups on the particle surface, which will cause oxidation reaction on the particles. UV light grafting polymerization of NIPAAm on the particle forms a thermosensitive polymer on the surface. Quartz crystal microbalance (QCM) was used to determine the quality of surface modified gold nanoparticales. The sensitivity of measuring gold nanoparticle by the surface characteristic of modified hydrophilic or hydrophobic QCM sensor is investigated. Plasma chemical deposition technique was used to deposit an organic thin film on the QCM sensor surface. The measured frequency changes on the hydrophobic gold nanoparticles by Hexamethyldisilzane plasma deposition (PD-HMDSZ) and by the PD-HMDSZ and oxygen plasma treatments are two and a half, respectively, of that of QCM sensor without plasma deposition. It is evident that QCM subjected to plasma treatment is easier to sense the gold nanoparticles and measure the frequency changes.