藉由奈米金屬結構產生的局域表面電漿共振，可以達成高敏感度的生物檢測，在生醫光電領域有很高的應用潛能。本文中我們介紹利用銀奈米結構所產生的局域增益光場應用於螢光分子之檢測上，不同幾何結構所造成的螢光增益效應不同，我們發現奈米圓柱在相同的條件下，對螢光亮度提升有最佳效果。另外，使用銀奈米孔洞所產生之局域表面電漿場，可以捕捉液體內隨機分佈之奈米金顆粒，進一步配合理論模擬，驗證奈米顆粒進入奈米孔洞時產生之暗場光學變化。

Localized surface plasmons in metallic structures can sensitively detect biomolecules and has very high potentials in the biomedical applications. In this text, we introduce our research of using silver nanostructures to enhance the detection of fluorescent molecules. Different shapes of structures were studied by the dark-field optical microscopy. Comparing to the triangular and rectangular structures, the rod-like structure has the best effect in the fluorescence enhancement. In addition, the localized plasmons generate an optical trap that can increase the immobilization of nano-objects. Using the theoretical simulations and the optical microscopy, we verified the trapping effect of gold nanoparticles in the metallic nanoholes.

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