陽極氧化鋁基板與蝕刻式快速熱退火製造侷限型表面電漿共振感測器進行生物分子之檢測

Abstract

在生物感測應用中，侷限型表面電漿共振感測技術因其無標記、動態和易操作的特性而受到廣泛關注。然而，降低製造成本並提高靈敏度仍然是一個挑戰。在本研究中，我們提出了兩種LSPR感測器製造方法，具有 (1) 易於生產；(2) 平方公分等級的感測面積和(3)高靈敏度的特性。第一種製程 (AAO-LSPR感測器) 涉及在多孔、緊密堆積和周期排列的陽極氧化鋁上蒸鍍不同厚度的金奈米陣列。第二種方法(eRTA-LSPR感測器)涉及優化蝕刻時間以在金薄膜上形成粗糙的表面，然後進行快速退火過程以生成隨機排列的奈米金粒子。兩者相比之下， AAO-LSPR感測器具有更高的靈敏度 (193.3 nm/RIU) 和低了一個數量級的最低檢測濃度，而eRTA-LSPR感測器則具備大量生產的商業潛力和更高的均勻性。我們還開發了一種光譜掃描演算法，以減少由於感測器表面微小差異引起的消光光譜標準偏差。在程式的幫助下，我們能夠實時觀察生物分子的反應情況以優化各種檢測參數並取得最佳結果。最終，成功使用AAO-LSPR感測器測量了濃度範圍為0.1至3 μg/mL的C反應蛋白 (CRP)和濃度範圍為1至10000 ng/mL的降鈣素原 (PCT)；eRTA-LSPR感測器則涵蓋了濃度範圍為1至10 μg/mL的CRP和濃度範圍為10至10000 ng/mL的PCT。本研究提出兩種LSPR感測器並以label-free的方式成功量測接近臨床參考值的生物分子，在臨床定點照護儀器上具有重要發展潛力。

Localized surface plasmon resonance (LSPR) has gained significant attention in biosensing due to its label-free, dynamic, and easy-to-operate nature. However, challenges remain in reducing fabrication costs and increasing sensitivity. This study proposes two LSPR sensor fabrication methods aimed at (1) ease of production, (2) cm² scale sensing area, and (3) high sensitivity. AAO-LSPR sensor involves creating nano-gold arrays with varying thicknesses on porous, closely-packed, and periodically arranged AAO. eRTA-LSPR sensor uses different etching times to form irregular surface undulations on gold, followed by RTA to generate randomly arranged nano-gold particles. Comparatively, the AAO-LSPR sensor shows higher sensitivity (193.3 nm/RIU) and a detection limit improved by an order of magnitude. In contrast, the eRTA-LSPR sensor has significant commercial potential due to its mass production capability and higher uniformity. Additionally, a spectrum mapping algorithm was developed to reduce the standard deviation of the extinction spectra caused by subtle surface differences. This program allowed real-time observation (approximately every 2 seconds) of biomolecule binding, optimizing various detection parameters. Ultimately, successful measurements were achieved using the AAO-LSPR sensor for CRP concentrations ranging from 0.1 to 3 µg/mL and PCT concentrations from 1 to 10,000 ng/mL. The eRTA-LSPR sensor covered CRP concentrations from 1 to 10 µg/mL and PCT concentrations from 10 to 50,000 ng/mL. This study proposes two LSPR sensor fabrication methods that successfully measure biomolecules near clinical reference values in a label-free manner, demonstrating significant potential for development in point-of-care clinical instruments.