可即時偵測一氧化氮之針尖狀水凝膠感測器

Abstract

本論文之主軸為製作出一高感測度針尖狀一氧化氮水凝膠感測器，將市售之一氧化氮感測分子1, 2-Diaminoanthraquinone (DAQ)混入水凝膠材料1, 2- Poly (2-hydroxyethyl methacrylate) (PolyHEMA)中。此感測器是藉由置入雙光纖架構於含有感測分子之水凝膠材料中，使感測器在偵測到一氧化氮時，可藉由水凝膠材料光吸收率改變，去調變接收光纖端所接受到的光訊號。本論文中，我們嘗試調整雙光纖架構中之入光光纖端及出光光纖端之距離，去製造出類開關狀態的感測器，並成功達成在感測器偵測到一氧化氮時，光訊號會有顯著的上升。 此針尖狀感測器之直徑僅有1.2mm 且被置於一1.6G醫療用針頭(直徑1.6mm)中，以方便應用於醫學治療及達到於偵測同時不傷害組織器官之效果。在感測能力上，我們成功地達到微莫耳(micro-Molar)等級之一氧化氮濃度量測，此量級非常接近一氧化氮於人體體內之濃度。並可藉由五分鐘內光訊號的變化量，去計算反應率來即時性的定量待測濃度。此即時性針尖狀偵測感測器可應用於監測中風及腦外傷等一氧化氮濃度會隨不同病理情況而改變之疾病。

In this thesis, we present a highly sensitive and sharp Nitric oxide (NO) sensing tip based on a homogeneously active optical waveguide made of the hydrogel Poly 2-hydroxyethyl methacrylate (PolyHEMA) which mixed with 1, 2-Diaminoanthraquinone (DAQ) as the probe molecule. This real-time solid-state hydrogel sensing tip is made by inserting two parallel optical fibers inside a PolyHEMA hydrogel waveguide. With controlling the distance between the two fibers, we create a switch-like sensor which the light in fibers has to propagate through the 1mm distance from the in-coming fiber to the out-coming fiber. The light intensity collected by the out-coming fiber therefore depends sensitively on the absorption coefficient changed by the NO concentration. The overall diameter of the sensing tip is only 1.2 mm and housed in a needle whose diameter is about 1.6 mm to avoid possible mechanical stress and distortion in practices. Such diameter is sharp enough for skin or organ penetration in medical applications above.