Researchers at Rensselaer Polytechnic Institute (NY, USA) have designed a novel approach to optical imaging. The new technique, utilizing a digital micromirror device, could efficiently and economically monitor multiple molecular interactions over several spectral bands in large fields of view, such as in organs or small animal models.
The findings published in Nature Photonics, detailed that sixteen colors of spatially linked information were simultaneously tracked over an area as large as several centimeters, capturing interactions occurring in billionths of a second. Expensive cameras and equipment typically used in fluorescence lifetime imaging (FLIM) and Förster resonance energy transfer (FRET) techniques were substituted for three single-pixel detection devices; a digital micromirror device.
Researchers utilized FLIM-FRET, an optical imaging technique, which relies on fluorescent-tagged molecules of interest. FLIM-FRET quantitatively measures fluorescence lifetime, indicative of the molecular environment and proximity between two similarly tagged molecules.
The FLIM-FRET technique has proven useful when studying drug/target interactions at a molecular level. However, the technique typically requires specialist equipment over long periods of time regardless of subject or desired molecule. Cameras capable of detecting only one ‘reporter’ molecule signal at a time are used to collect information-rich data, but this collection can take hours as cameras slowly record information from their full fields of vision.
However, using a new approach, the team were able to record precise 3D images in 10 minutes, utilizing the digital micromirror device based spatial light modulators and a mathematical sampling technique based on a Hadamard transform.
Xavier Intes (Rensselaer Polytechnic Institute) stated that his team had “developed a smart way to acquire a massive amount of information in a short period of time. Our approach is faster and less expensive than existing technology without any compromise in the precision of the data we acquire.”
Optical imaging is typically preferred in biomedical fields as techniques require less exposure to radiation. Intes concluded: “This is a new platform, a new option in macroscopy, and we think it will have traction in multiple applications in the biomedical arena.”
Sources: Pian Q, Yao R, SinsuebphonN, Intes X. Compressive hyperspectral time-resolved wide-field fluorescence lifetime imaging. Nat Photonics 11, 411–414 (2017); www.eurekalert.org/pub_releases/2017-08/rpi-nbt081817.phpw