紙基與花瓣微奈米結構運用於超高靈敏度表面增強拉曼散射技術

在本篇論文中，利用天然材料為基板，以緊密排列的微奈米結構，製作出高靈敏度與高空間再現性的環境友善表面增強拉曼散射基板。在本篇論文的第一部分，利用準分子雷射退火，於鍍有金屬薄膜的紙基材，藉由控制金屬膜厚與雷射轟擊參數，以形成高密度金屬奈米粒子，利用奈米尺度金屬間距產生耦合電場增強，製作表面增強拉曼散射基板。並且利用全氟辛基三氯矽烷蒸鍍於紙上，使紙表面擁有疏水性質，藉此濃縮侷限待測物，使得量測訊號增益。因此紙基材表面增強拉曼散射基板能夠量測至濃度為原子等級10-18 M之4-胺基苯硫酚(4-ATP)，展示了一個便宜、製程快速而且為可拋棄式之超高靈敏度表面增強拉曼散射基板。而在本篇論文的第二部分，我們提出了一環境友善製程，為利用生物疏水結構，藉由超疏水濃縮效應，於玫瑰花花瓣上濃縮聚集銀奈米粒子，製作高增益的表面增強拉曼散射基板。由於濃縮之奈米粒子間隔亦為奈米尺度，由局域性表面電漿共振現象所引發之電場增益將會大幅增強，進而提升拉曼量測訊號。而玫瑰花瓣表面的疏水性除了濃縮銀奈米粒子之餘，同時於待測物量測時，也能夠使待測物濃縮聚集而提升其量測效率。而量測代表待測物羅丹明(R6G)，而能夠量測到10-15 M的低濃度。展示了一個利用天然材質與結構，只需要簡單製程即可有優異表現的表面增強拉曼散射基板。本論文中，利用天然材料所製備的表面增強拉曼散射基板，皆由於其之簡單製程與成本低廉，對於未來廣泛應用於實際分析量測上，擁有相當大的潛力。

關鍵字

表面增強拉曼散射基板；局域性表面電漿共振現象；雷射熱退火；紙基材；生物疏水結構

並列摘要

In this thesis, practical methods of preparing highly sensitive and reproducible surface-enhanced Raman scattering (SERS) substrates by using natural substrates to create closely arranged metallic micro-nanostructures were developed. In the first part of the thesis, we fabricated paper-based SERS substrates with highly dense metal nanoparticles (NPs) obtained by fine-tuning the excimer laser-induced annealing process. The high electric field enhancement caused by the nanogaps among metal NPs on the fibers of paper substrates can be achieved. Besides, by using the perfluorooctyl- trichlorosilane treatment, paper substrates could be changed to hydrophobic. Therefore, the analytes could be condensed as well as confined with enhancement of Raman scattering signal. Therefore, paper-based surface-enhanced Raman scattering substrates are able to detect down to attomalar (10-18 M) for 4-ATP. We accomplish inexpensive, easy-prepare, disposable SERS substrates with ultrahigh sensitivity and reproducibility. In the second part of the thesis, we developed an eco-friendly process for SERS on the basis of bio-hydrophobic natural substrates. By means of superhydrophobic condensation effect, the Ag NPs could be condensed and gathered on the rose petal to prepare highly efficient SERS substrate. The narrow interparticle nanogaps among the adjacent Ag NPs can dramatically enhance electric field due to localized surface plasma resonance (LSPR) and the enhancement of Raman scattering can also rise. The hydrophobic property of rose petal surface is also able to condense analytes for efficient Raman detection. The limit of detection for R6G on a rose-based SERS substrate could down to 10-15 M. A great SERS substrate can be accomplished with a simple fabrication by means of the nature materials and structures. In this thesis, the natural, ultrahigh sensitivity and low-cost SERS substrates have been developed and can provide great potential to apply Raman detection extensively in practical analysis.