Abstract

A new up to the visible range absorbing and at 460 nm fluorescing 4-trifluoromethylcarbostyril derivative of diethylenetriaminepentaacetic acid (DTPA) was synthesized. After formation of an europium (III)-complex intense antenna mediated lanthanide luminescence was observed. Without loss of the antenna function, the complex was entrapped into various sol–gel and ormosil (organically modified siloxanes) matrices. Luminescence spectra were then found to be independent of pH changes in the range 1–10. No leaching was observed and photostability was excellent. This stability allowed us to study the influence and pH response of bromothymolblue (BTB) as co-immobilized non-fluorescent indicator by fluorescence. A single sensor layer based on tetramethoxysilane (TMOS) doped with the Eu +3-complex and about 3.5 equivalents BTB was found to be most appropriate for purposes of sensing pH over the broad pH range 5–9. The apparent p K a was 7.29 at ionic strength 0.1 and 6.05 at ionic strength 1.0 (KCl).

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.