Chemosensing in deep red: A squaraine-based fluorescent chemosensor for pH.

Date

1997-10-20

Author

Isgor, YG
Akkaya, EU

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We have synthesized and spectrally characterized a squaraine-based fluorescent chemosensor for pH. This chemosensor unlike many others, works in 100 % aqueous solutions, signalling the pH change from 10 to 7 by a 11-fold increase in the emission intensity at 651 nm, when excited at the isosbestic point (614 nm). The average pK(a) for the ionizable groups is found to be 8.8. The chemosensor with its molar extinction coefficient > 200,000 and the quantum yield of 0.2, yield an impressive intrinsic brightness value of 40,000. (C) 1997 Elsevier Science Ltd.

Subject Keywords

Organic Chemistry, Biochemistry, Drug Discovery

URI

https://hdl.handle.net/11511/65632

Journal

TETRAHEDRON LETTERS

DOI

https://doi.org/10.1016/s0040-4039(97)01745-0

Collections

Department of Chemistry, Article

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Citation Formats

Y. Isgor and E. Akkaya, “Chemosensing in deep red: A squaraine-based fluorescent chemosensor for pH.,” TETRAHEDRON LETTERS, pp. 7417–7420, 1997, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/65632.