Förster resonance energy transfer (FRET) is a difficult technique to perform but is helped by the stability, consistency and easy of use provided by CoolLED's LED excitation systems.
The CoolLED pE-2 system is ideally suited for FRET applications. The ability to control intensity separately for each excitation channel means that intensity can be set optimally for each fluorophore. Common FRET filter sets use a single passband excitation filter but with a CoolLED solution you can choose to select two separate excitation filters and have the added benefit of being able to view both FRET wavelengths independently. An excitation filter wheel is therefore not required as the individual excitation filters can be placed within the optical path of the pE-2 Collimator. This means that fast switching in microseconds can be achieved without the delay or vibration from moving parts.
With a CoolLED LED system for FRET, you have....
- Independent wavelength intensity control
- No need for an excitation filter wheel
“We have recently established a visualisation process for small GTPase activity using FRET. We used a CoolLED pE-2 LED system to excite the fluorophores. It proved to be an essential tool in the acquisition and processing of the FRET images by its ability to minimise photobleaching. " K Aoki & M Matsuda, School of Biostudies, Kyoto University
Example 1: FRET using GFP/RFP
CoolLED pE-2 excitation system with excitation at 490nm and 585nm
Example 2: FRET using CFP/YFP
CoolLED pE-2 excitation system with excitation at 440nm and 500nm