Bright F V, Poirier G E, Hieftje G M
Department of Chemistry, Indiana University, Bloomington, IN 47405, U.S.A.
Talanta. 1988 Feb;35(2):113-8. doi: 10.1016/0039-9140(88)80048-1.
A fluorimetric ion sensor based on fiber optics has been developed that employs Rhodamine 6G hydrophobically and electrostatically "trapped" on a Nafion film. The sensor is based on the measurement of quenching or enhancement of the Rhodamine 6G fluorescence by various ions. It was found that ions such as Co(2+), Cr(3+), Fe(2+), Fe(3+), Cu(2+), Ni(2+) and NH(+)(4) rapidly quench the Rhodamine 6G fluorescence at an initial rate that depends on the concentration of the ion. This quenching is then readily reversed by the addition of "reverser" ions such as H(+), Li(+), Na(+), K(+), Ba(2+), Ca(2+), Mn(2+), Zn(2+) and Mg(2+). Again, the initial rate for the attainment of the original fluorescence was found to depend on the concentration of the reverser ion. Therefore, by monitoring the quenching directly the concentration of quencher ions can be determined. In addition, by loading the film with quencher and monitoring the initial rate of return towards the original baseline signal, it is possible to determine non-quenching ions.
一种基于光纤的荧光离子传感器已被开发出来，它采用疏水性和静电性“捕获”在Nafion膜上的罗丹明6G。该传感器基于通过各种离子对罗丹明6G荧光的猝灭或增强的测量。研究发现，诸如Co(2+)、Cr(3+)、Fe(2+)、Fe(3+)、Cu(2+)、Ni(2+)和NH(+)(4)等离子会以取决于离子浓度的初始速率迅速猝灭罗丹明6G的荧光。然后，通过添加诸如H(+)、Li(+)、Na(+)、K(+)、Ba(2+)、Ca(2+)、Mn(2+)、Zn(2+)和Mg(2+)等“反转离子”，这种猝灭很容易被逆转。同样，恢复到原始荧光的初始速率也被发现取决于反转离子的浓度。因此，通过直接监测猝灭，可以确定猝灭离子的浓度。此外，通过在膜中加载猝灭剂并监测恢复到原始基线信号的初始速率，可以确定非猝灭离子。
