Response Characteristics and Mathematical Modeling for a Nitric Oxide Fiber-Optic Chemical Sensor
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- 作者：Xiangji Zhou and Mark A. Arnold
- 刊名：Analytical Chemistry
- 出版年：1996
- 出版时间：May 15, 1996
- 年：1996
- 卷：68
- 期：10
- 页码：1748 - 1754
- 全文大小：381K
- 年卷期：v.68,no.10(May 15, 1996)
- ISSN：1520-6882
文摘
A novel fiber-optic sensor for nitric oxide is constructedby holding a small amount of an internal reagent solutionat the tip of a fiber-optic bundle with a piece of gas-permeable membrane. Nitric oxide diffuses across themembrane into this internal solution, where a chemiluminescent reaction between nitric oxide, hydrogen peroxide, and luminol takes place. The resulting lightintensity is related to the concentration of nitric oxideinthe sample. Results are presented from experiments tooptimize the magnitude and rate of the sensor response.The resulting sensor possesses a limit of detection of1.3
M, a response time of 8-17 s, and a dynamic rangefrom5 to 40 M. A mathematical model is derived toexplainthe sensor response as a function of time. Oxidationofnitric oxide by ambient oxygen and mass transport ofnitric oxide through the gas-permeable membrane areconsidered in this model. The excellent agreement between experimental data and model predictions indicatesthat the oxidation of nitric oxide by oxygen is a majorfactorin this measurement, regardless of transducer element.The model further indicates a reaction rate constantforthe oxygen oxidation of nitric oxide of 9.5(±0.5) ×106M-2 s-1 and adiffusion coefficient for nitric oxide in thesilicone membrane of 5.0(±0.2) ×10-11 m2s-1 at 30
C.
M, a response time of 8-17 s, and a dynamic rangefrom5 to 40 M. A mathematical model is derived toexplainthe sensor response as a function of time. Oxidationofnitric oxide by ambient oxygen and mass transport ofnitric oxide through the gas-permeable membrane areconsidered in this model. The excellent agreement between experimental data and model predictions indicatesthat the oxidation of nitric oxide by oxygen is a majorfactorin this measurement, regardless of transducer element.The model further indicates a reaction rate constantforthe oxygen oxidation of nitric oxide of 9.5(±0.5) ×106M-2 s-1 and adiffusion coefficient for nitric oxide in thesilicone membrane of 5.0(±0.2) ×10-11 m2s-1 at 30C.