Evaluation of Acridine in Nafion as a Fluorescence-Lifetime-Based pH Sensor
Evaluation of Acridine in Nafion as a Fluorescence-Lifetime-Based pH Sensor
复制标题
Nafion 中吖啶作为基于荧光寿命的 pH 传感器的评价
作者：
Alan G. Ryder;Sarah Power;T. Glynn
我们报告了一种新的荧光寿命为基础的pH传感方法，利用吖啶纳入Nafion（AcNaf）作为荧光指示剂。使用380 nm发光二极管（LED）激发AcNaf传感器，并在450和500 nm处测量荧光寿命。研究了吖啶在磷酸盐缓冲溶液中的荧光行为及其与Nafion膜的相互作用。结果表明，将吖啶掺入到Nafion中将表观基态pKa从1.545改变到1.599，而表观激发态pKa* 仅略有变化（在0.1 M磷酸盐缓冲液中为1.944）。AcNaf膜显示出良好的pH响应，在pH 8至10的范围内，平均寿命的变化为1.19 ns（在450 nm的发射波长处）。我们还表明，激发态质子化不会发生在AcNaf传感器膜和氯化物淬火不能发生，因为选择性渗透的性质的Nafion。我们还讨论了Nafion的独特结构如何影响吖啶在不同pH值下的荧光行为，并研究了缓冲液浓度对表观pKa和pH传感能力的影响。
We report a novel fluorescence-lifetime-based pH sensing method that utilizes acridine incorporated into Nafion (AcNaf) as the fluorescent indicator. The AcNaf sensor is excited using a 380 nm light emitting diode (LED) and the fluorescence lifetimes are measured at 450 and 500 nm. The fluorescence behavior of acridine as a function of pH in aqueous phosphate buffers and incorporated into the Nafion membrane has been investigated. The results show that incorporating acridine into Nafion changes the apparent ground-state pKa from ∼5.45 to ∼9, while the apparent excited-state pKa* is only slightly changed (∼9.4 in 0.1 M phosphate buffer). The AcNaf film shows a good pH response with a change in average lifetime of ∼19 ns (at an emission wavelength of 450 nm) over the pH 8 to 10 range. We also show that excited-state protonation does not occur in the AcNaf sensor film and that chloride quenching cannot occur because of the permselective nature of Nafion. We also discuss how the unique structure of Nafion affects the fluorescence behavior of acridine at various pH values and examine the impact of buffer concentration on apparent pKa and pH sensing ability.
影响因子：
7.4
作者：
SZMACINSKI, H;LAKOWICZ, JR
通讯作者：
LAKOWICZ, JR
使用相位调制荧光测定法测量临床浓度的钾和钠。
DOI：
10.1016/s0925-4005(99)00235-x
发表时间：
1999
期刊：
Sensors and actuators. B, Chemical
影响因子：
--
作者：
Szmacinski,Henryk;Lakowicz,JosephR
通讯作者：
Lakowicz,JosephR
影响因子：
2.9
作者：
Lin, HJ;Herman, P;Lakowicz, JR
通讯作者：
Lakowicz, JR