二次曲線V型光柵表面電漿生物感測晶片

Quadratic v-groove grating surface plasmon biosensor

周成澤

指導教授 ： 李明昌

國立清華大學/電機資訊學院/光電工程研究所/碩士(2012年)

摘要

表面電漿生物感測技術擁有比其他生物感測方法有更高的靈敏度，如今已經發展出很多不同的表面電漿生物感測方法。本論文主要是討論光柵式表面電漿感測方法。此方法最主要是藉由觀察反射頻譜的變化量，而去感測光柵表面物質的變異。我們利用Finite Difference Time Domain (FTDT)這個方法去模擬後發現改變光柵表面形貌會影響反射頻譜的特性，進而設計出二次曲線V型光柵，此種光柵比起傳統的矩形光柵在同樣深寬比下其反射頻譜的頻寬比較窄。經由我們實驗證實，擁有較窄頻寬的表面電漿感測晶片其系統的解析度較高，如此就可以偵測到更細微的訊號。接著我們整合微流道系統，將不同濃度的食鹽水注入晶片中測得我們晶片的敏感度(Sensitivity)為820(nm/RIU)。最後利用biotin-avidin這個生物流程去測試生物感測晶片的效能，測試結果顯示反射頻譜偏移量會隨著不同濃度的avidin溶液做線性的偏移，如此我們就可以輕易做生物檢測的定量分析。

關鍵字

表面電漿 ； 生物檢測

並列摘要

Surface plasmon for biosensing applications has high sensitivity. There are many types of surface plasmon biosensors today. We focus on the grating-based surface plasmon biosensors. The grating-based SP biosensor detects the biomolecule through interrogating the shift of reflection spectrum. By the simulation method of Finite Difference Time Domain (FTDT), we found that the bandwidth is generally related to the profile of the grating. A new grating-based surface plasmon biosensor is proposed. This surface plasmon grating featured by quadratic V-grooves showed a narrower spectral bandwidth, compared with conventional rectangular gratings with the same aspect ratio of the open trench. The experimental result confirmed improved sensor resolution. The sensitivity was measured to be 820 (nm/RIU) with various concentrations of salt solution. Real-time detection of avidin bound on biotin was presented.

並列關鍵字

surface plasmon ； biosensor

參考文獻

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