Definition and Use of the Experimental Sensible Parameters To Characterize Sensitivity and Precision of a Generic Oxygen Optical Sensor
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- 作者：Denis Badocco ; Paolo Pastore
- 刊名：Analytical Chemistry
- 出版年：2008
- 出版时间：March 15, 2008
- 年：2008
- 卷：80
- 期：6
- 页码：2091 - 2096
- 全文大小：175K
- 年卷期：v.80,no.6(March 15, 2008)
- ISSN：1520-6882
文摘
Experimental data, obtained with an oxygen optical sensorconstituted by a polysulfone layer embedding ruthenium(II)(4,7-diphenyl-l,l0-phenanthroline)octylsulfate (Ru(dpp)OS), were rationalized by using the digital simulationtechnique and generalized for different sensors. Theexperimental, asymmetric, emission shape was used todefine two sensible parameters, ASY (asymmetry factor)and 
I% (percent variation of emission intensity), tocharacterize the sensitivity of a generic oxygen opticalsensor (represented by the Stern-Volmer constant, 
cribe/journals/ancham/80/i06/eqn/ac702202te10001.gif">).Correlations between ASY and cribe/journals/ancham/80/i06/eqn/ac702202te10002.gif"> and between I% andcribe/journals/ancham/80/i06/eqn/ac702202te10003.gif"> were established, and a double working curve wasproposed to evaluate with a single light emission measurement the cribe/journals/ancham/80/i06/eqn/ac702202te10004.gif"> value with the best precision. Sensitivemembranes (-log cribe/journals/ancham/80/i06/eqn/ac702202te10005.gif"> = pcribe/journals/ancham/80/i06/eqn/ac702202te10006.gif"> < 0.5) had high precisiononly for low %O2 values; poorly sensitive membrane(pcribe/journals/ancham/80/i06/eqn/ac702202te10007.gif"> > 2.5) had constant but scarce precisions in alarge %O2 interval. For %O2 up to 21% (air) good valuesare pcribe/journals/ancham/80/i06/eqn/ac702202te10008.gif"> = 0.5-1.0. In order to monitor a wider %O2range, pcribe/journals/ancham/80/i06/eqn/ac702202te10009.gif"> = 1.5-2.0 are good choices. A simplemathematical model allowed one to estimate the oxygendiffusion coefficient inside the layer, DO2, and its solubilityin the polymer matrix, sO2, from the simple measurementof the membrane thickness, response time, t90, andluminescence lifetime. DO2 = 2 × 10-8 cm2 s-1 andsO2 = 2.2 × 10-3 mol atm-1 cm-3 were estimated for ourmembranes. The proposed working curves gave very goodresults even with literature data.
I% (percent variation of emission intensity), tocharacterize the sensitivity of a generic oxygen opticalsensor (represented by the Stern-Volmer constant, I% and