Oswald, Bernhard and Patsenker, Leonid and Duschl, Josef and Szmacinski, Henryk and Wolfbeis, Otto S. and Terpetschnig, Ewald (1999) Synthesis, Spectral Properties, and Detection Limits of Reactive Squaraine Dyes, a New Class of Diode Laser Compatible Fluorescent Protein Labels. Bioconjugate Chemistry 10 (6), pp. 925-931.
Download (248kB) - Repository staff only
We describe the synthesis and spectral characterization of two reactive long-wavelength fluorescence labels (Sq635-m and Sq635-b), having either one or two N-hydroxysuccinimidyl esters. Both are squaraine derivatives and consist of a cyanine-type chromophore and a central squarate bridge. To improve water solubility, we introduced two sulfonic acid groups into the heterocyclic ring systems, and for covalent attachment to proteins, a reactive N-hydroxy-succinimide ester (NHS ester) was synthesized. The squaraine markers exhibit low quantum yields in water (φ = 0.15) and high quantum yields (φ = 0.6−0.7) when bound to proteins. The absorption maxima at 635 nm in water and at approximately 645 nm when bound to proteins allow excitation with commercially available diode lasers. The detection limit of a representative squaraine dye in blood was estimated to be half that of a commonly used fluorophore.
|Institutions:||Chemistry and Pharmacy > Institut für Analytische Chemie, Chemo- und Biosensorik > Chemo- und Biosensorik (Prof. Otto S. Wolfbeis)|
|Subjects:||500 Science > 540 Chemistry & allied sciences|
|Created at the University of Regensburg:||Unknown|
|Deposited On:||06 Jun 2011 13:03|
|Last Modified:||21 Jul 2011 02:14|