紅外光檢測少量樣品之方法開發

摘要在以往的紅外光譜感測技術中，偵測水溶液有機樣品，受限於水對紅外光譜的影響，並無法直接獲得欲偵測物的光譜技術，為了提高偵測的靈敏度，開始有人將固相微量萃取技術應用於紅外光譜學的研究上。然而已發表的現行方法中，為了偵測的靈敏度考量，往往需要大量的樣品，這對於不易取得之樣品如生物檢體、尿液、血液及有高經濟價值之樣品如光學異構物等，卻都不適用。在目前生物感測原件日趨微小化的趨勢下，對於少量樣品的偵測方法及理論基礎，也應即早建立。與此本論文特別針對少量水溶液的樣品，提出以紅外光測量技術中之單次反射及多次反射吸收法結合固相微量萃取測量法來進行偵測，研究中更著墨於適用理論的建立。最終研究結果發現，對於分配係數大的樣品，其實並不需要太大量的樣品及可以得到不錯的偵測結果，而本論文所提出的方法對於定量測量有優良的線性表現，偵測極限也有ppb級的靈敏度，加上有可再生使用、測量快速的優點，研究者可以依樣品的特性經簡單的計算即可得知是否適合利用這兩種方法來進行檢測。

關鍵字

反射吸收法；少量樣品；固相微量萃取；紅外光

並列摘要

ABSTRACT Infrared (IR) chemical sensors can provide fast and easy ways in detection of organic compounds in aqueous solutions. However, large sample volumes were typically required in IR sensing methods to increase the sensitivity. For samples, such as biological samples, drugs, natural products, were typically limited in sample volumes, the applications of IR chemical sensing methods to these types of compounds were limited. To increase the applicability of IR sensing methods in detections of these types of compounds, methods based on combination of solid phase microextraction (SPME) and IR sensing method were developed for detection of samples in low sample volumes. Reflection absorption type of IR sensing technique was used. However, two types of detections can be distinguished in terms of optical systems. In the first type of method, SPME phase was coated on a reflection element. After sample placed on the SPME phase for certain period of time, the absorbed analytes were detected by single reflection optical system. In the second method, the named hollow waveguide sampler was used. Sample was placed into the sampler and detected by multi-reflection mode. To prove that above two methods can be used to detect samples with low volumes, we theoretically examined the relationships between each parameter and presented in Chapter 2. The results of SPME/one-reflection IR method and SPME/multi-reflection IR method were presented Chapters 3 and 4, respectively. Both methods provided enough sensitivity in detection of organic compounds in aqueous solution with sample volumes lower than 300 microliter. High linearity between concentration and IR signals indicates that both methods can be used for quantitative analyses.

並列關鍵字

SPME ； Low volume sample ； FT-IR ； Reflection-Absorption(RA) ； infrared

參考文獻

1.Griffiths, P.R., Fourier Transform Infrared Spectrometry

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14.Degel, F., Clinical Biochem. 1996, 29, 529

15.Djozano, D.；Farajzadeh, M. A., Anal. Letters. 1998, 31,2093

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紅外光檢測少量樣品之方法開發

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