Fluorescence Lifetime Measurements of BODIPY™ and Alexa™ Dyes on Chronos™ and K2™

Yevgen Povrozin and Ewald Terpetschnig
ISS, Inc.

Introduction

Chronos™ is the first frequency-domain fluorometer that enables measurement of time-resolved data with laser diodes (LDs) and light emitting diodes (LEDs). Chronos™ offers all the benefits of a full time-resolved fluorometer but at an affordable price. Chronos™ is fully automated using Vinci, a Windows-based software and is upgradeable for steady-state measurements.

Figure 1. Schematic drawing of Chronos™, the frequency-domain fluorometer from ISS.

With over 100 installed units all over the world, the K2™ family of multifrequency cross-correlation phase and modulation fluorometers represents a solid and well-proven approach to fluorescence and phosphorescence instrumentation for the research laboratory. Its optical design and automatic instrument control are state-of-the-art for steady-state and time-resolved fluorescence measurements. Full automation and the user-friendly Vinci software package make the instrument easy to use for both the student and the scientist.

Figure 2. Schematic drawing of K2™, the steady-state and time-resolved fluorometer from ISS.

K2™ utilizes a Pockels Cell for light modulation and is capable of measuring lifetimes as low as a few hundred picoseconds using a conventional Xenon lamp (see measurement example below).

Lifetime measurements on Chronos™ are fast and easy. Switching light sources can be done in matter of minutes. LEDs and LDs provide excellent light sources with large modulation depth – up to 100% at certain frequencies, and they can be easily modulated up to 250 MHz (some up to 500 MHz). In this context we would like to refer you to the ISS Application Note: Frequency Domain Spectroscopy Using 280-nm and 300-nm LEDs.

For a demonstration of the capabilities of Chronos™ and K2™ we have acquired lifetime measurements on a series of BODIPY™ and Alexa™ dyes.

Experimental Data