極低濃度腺嘌呤分子的檢測對於生物學和醫學研究有著非常重要的應用。如何開發具有高增強效應、高穩定性、低成本且再現性佳的表面增強拉曼光譜(SERS, Surface-Enhanced Raman Scattering)感測器是一個很大的挑戰。本研究將蝕刻後的矽基板通過浸泡硝酸銀水溶液，使銀沉積在部分沒有覆蓋石墨烯的球形銅結構上，形成緊密堆積的銀奈米顆粒簇，奈米銀粒子間的間隙感應出非常高的局部電場，在感測器上產生許多熱點，並有助於增強測得的拉曼散射訊號。

我們嘗試在感測器上濺鍍不同厚度的銅和浸泡不同時間的硝酸銀，製備出沉積在分散球形銅結構上的奈米銀顆粒簇表面增強拉曼光譜(SERS)感測器，在不同的酸鹼環境下，腺嘌呤分子通過靜電吸附和官能基鍵結與銀互相作用，其檢測極限非常低，可檢測濃度低至10-12M的腺嘌呤水溶液。

Adenine molecules are important for biological and medical research and applications. The detection of low concentration of adenine molecules is thus desirable. This paper reports a silver-based surface enhanced Raman scattering (SERS) sensor capable of detecting 10-12 M adenine molecules in water. Closely spaced silver nanoparticles are grown by chemical plating on discrete copper bumps located in etched holes in a silicon substrate. The copper bumps and silicon substrate are covered by rapid thermal CVD graphene with a high-density of domain boundaries and defects exhibiting a strong D-band besides a G-band and a 2-D band in the Raman spectrum. The graphene serves as a mask to only allow chemical plating of silver to occur on copper surface which is not covered by graphene or through defects of graphene covering copper. The pH value of adenine water solution is altered to optimize interactions and adsorption of adenine with the sensor surfaces. The lowest detection limit of 10-12 M adenine in pH9 water solution is achieved.

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