Seta-633 - a NIR fluorescence lifetime label for low-molecular-weight analytes.
We describe the photophysical properties of Seta-633, a commercially available near-infrared (NIR) dye, and its use as a fluorescent label to study the interaction between low-molecular-weight analytes and proteins using fluorescence lifetime as the readout parameter. In a model assay, we demonstrate that a biotinylated Seta-633 tracer binds to antibiotin with high specificity. Importantly, the lifetime of Seta-633-biotin increases about 1.8-fold upon binding to a specific antibody (antibiotin, MW = 160 kDa), while the titration with bovine serum albumin (BSA) or nonspecific antibody does not result in a noticeable change in lifetime. This behavior is contrary to that of fluorescent tracers like Cy5 or Alexa 647, which typically exhibit much smaller lifetime changes upon binding to antibodies.
Povrozin
Yevgen A
YA
SSI Institute for Single Crystals of the National Academy of Sciences of Ukraine, Kharkov 61001, Ukraine.
Kolosova
Olga S
OS
Obukhova
Olena M
OM
Tatarets
Anatoliy L
AL
Sidorov
Vadim I
VI
Terpetschnig
Ewald A
EA
Patsenker
Leonid D
LD
D000906:Antibodies / Q000276:immunology; D001710:Biotin / Q000276:immunology; D005453:Fluorescence; D005456:Fluorescent Dyes / Q000737:chemistry*; D006207:Half-Life; D007259:Infrared Rays; D011506:Proteins / Q000737:chemistry*
D000906:Antibodies; D005456:Fluorescent Dyes; D011506:Proteins; D001710:Biotin