Molecular design, characterization, and application of multiinformation dyes (MIDs) for optical chemical sensings. 3. Application of MIDs for lambda(max)-tunable ion-selective optodes

By utilizing "multiinformation dyes (MIDs)", which have plural spectral cha nge characteristics such as an absorption maximum wavelength (lambda(max)) shift based on a polarity change and an absorbance change due to protonatio n, novel lambda(max)-tunable ion-selective optodes were proposed and prepar ed by employing MIDs with membrane solvents having different polarities. Fo r controlling the detecting lambda(max) of the optode, the novel polar memb rane solvent [2-[[6-(2-nitrophenoxy)hexyl]oxy]methyl]isobutane-1,3-diol was designed and synthesized, which was used together with a typical membrane solvent nitrophenyl octyl ether. By mixing these two membrane solvents, the lambda(max) position of the optode detection wavelength can be shifted and controlled and was successfully applied to a lambda(max)-tunable Li+-selec tive optode based on a highly Li+-selective ionophore TTD14C4. The lambda(m ax) tuning technique is useful for preparing an optode system using a low-c ost light source such as a light-emitting diode or a popular laser.