Fluorescence lifetime bioimaging - at a ridiculously low cost.
the paper in Optica (outside the paywall)
Blind and reference-free fluorescence lifetime estimation via consumer time-of-flight sensors
AYUSH BHANDARI,1, CHRISTOPHER BARSI,2 AND RAMESH RASKAR1
1Media Laboratory, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, USA 2Commonwealth School, 151 Commonwealth Avenue, Boston, Massachusetts 02116, USA
Fluorescence lifetime imaging (FLI) is a popular method for extracting useful information that is otherwise unavail- able from a conventional intensity image. Usually, however, it requires expensive equipment, is often limited to either distinctly frequency- or time-domain modalities, and demands calibration measurements and precise knowledge of the illumination signal. Here, we present a generalized time-based, cost-effective method for estimating lifetimes by repur- posing a consumer-grade time-of-flight sensor. By developing mathematical theory that unifies time- and frequency- domain approaches, we can interpret a time-based signal as a combination of multiple frequency measurements. We show that we can estimate lifetimes without knowledge of the illumination signal and without any calibration. We experimentally demonstrate this blind, reference-free method using a quantum dot solution and discuss the method’s implementation in FLI applications.