本研究在有機相中合成出具有磁性的FePt奈米粒子，並將其表面以SiO2包覆，接著再加入N-[3-(Trimethoxysilyl)propyl]ethylenediamine，藉此合成出表面帶正電且溶於水中的FePt@SiO2，再加入以檸檬酸鈉熱還原法製備表面帶負電之金奈米粒子 (gold nanoparticles，Au NPs)，經由兩者之間的靜電作用力使金奈米粒子能吸附於表面並且有良好的分散性，而製備出金奈米粒子/氧化矽/鐵鉑奈米複合物，FePt@SiO2@Au能夠提升對於微生物的接觸面積進而提高表面增強拉曼光譜 (surface-enhanced Raman scattering，SERS)偵測的靈敏度，可用於偵測小分子腺嘌呤 (adenine)、微生物金黃色葡萄球菌 (S. aureus)之SERS訊號，最後藉由改變金奈米粒子與氧化矽/鐵鉑之間的比例以及表面改質之藥劑的濃度，可控制金奈米粒子的粒子間距，藉此尋找最佳SERS增強效應，以應用於生物檢測。

In this research, iron/platinum nanoparticle was functionalized by coating SiO2 and amino-silane. Simultaneously, the citrate-capped gold nanoparticles (AuNPs) were produced through the traditional citrate thermal reduction method. The resulting AuNPs were then adsorbed to FePt@SiO2 due to electrostatic interaction. FePt@SiO2@Au exhibited higher surface-area between the substrate and microorganisms, thus enhancing surface-enhanced Raman scattering (SERS) sensitivity. FePt@SiO2@Au substrate can be widely used in SERS detection of small molecules (adenine) and microorganisms (S. aureus). Furthermore, this study demonstrated that the morphology and particle spacing of FePt@SiO2@Au can be controlled through the concentration of N-[3-(Trimethoxysilyl)propyl]ethylenediamine and the ratio of the proportion between AuNPs and FePt@SiO2, thereby optimizing the SERS enhancement effect. Thus these nanohybrids can be used for biosensing.

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