ION-SENSITIVE AND SELECTIVE ACTIVE WAVE-GUIDE OPTODES

Citation
H. Hisamoto et al., ION-SENSITIVE AND SELECTIVE ACTIVE WAVE-GUIDE OPTODES, Analytica chimica acta, 342(1), 1997, pp. 31-39
Citations number
29
Categorie Soggetti
Chemistry Analytical
Journal title
ISSN journal
00032670
Volume
342
Issue
1
Year of publication
1997
Pages
31 - 39
Database
ISI
SICI code
0003-2670(1997)342:1<31:IASAWO>2.0.ZU;2-F
Abstract
A novel polymer waveguide (active waveguide) type optode possessing th e advantages of both selective analyte determination and optical signa l propagation was developed. The noteworthy concept of this active wav eguide is the integration of plural functions into the planar waveguid e itself, such as molecular recognition, color change, and light propa gation. In order to demonstrate this concept, the analyte sensing laye r is utilized as the light propagating layer. An ion-selective optode membrane consisting of a plasticized poly(vinylchloride) (PVC) membran e containing a neutral ionophore and a color changeable lipophilic ani onic dye was used as the planar active waveguide sensing layer. The pr inciple of the response of this active waveguide is based on the measu rement of the output light signal intensity in which this light is pro pagated through the color changeable PVC membrane phase, and its inten sity is decreased by interaction with the analyte ions. In this report , calcium and sodium ion-sensitive waveguides were prepared based on o ur developed neutral ionophores. Comparison of the experimental respon ses between the novel active waveguide optode and a commonly utilized conventional waveguide optode based on evanescent wave spectrometry de monstrated that the sensitivity of the active waveguide optode is obvi ously greater than that of the conventional waveguide optode. This con cept of an active waveguide fully demonstrates the advantageous proper ty of a planar waveguide with respect to highly sensitive and selectiv e optical chemical sensing.