BIOBRIEFPAPER
Fluorescence polarization ratiometric microscopy is more than ten times faster than fluorescence lifetime imaging, the lab standard, and runs on common two photon microscopes.
A new two-photon imaging recipe called FPRM tracks the fuel gauge inside living cells in real time, more than ten times faster than the lab's standard method, according to a Science Advances paper.
Fluorescence polarization ratiometric microscopy (FPRM) reads the unbound form of NADH, a molecule that researchers use as an indicator of metabolic state. The authors report that the recipe is more than an order of magnitude faster than fluorescence lifetime imaging (FLIM), the workhorse for separating bound and unbound NADH, and runs on standard two-photon microscopes with a single extra calculation.
The team validated FPRM in 2D and 3D collagen matrices, the bioengineered platforms standard to cancer metabolism research, watching ratiometric numbers track expected shifts under pharmaceutical and environmental perturbations. The same parameters also correlated with cell morphology and migration.
FPRM is a correlation method, not a direct flux measurement. The >10x speed claim is author-stated, and the paper has not yet been independently benchmarked against FLIM across instruments. FLIM remains a well-validated approach, and the new work does not displace it.
The recipe is implementable today in any competent two-photon lab, and the ratiometric output is designed to be comparable across instruments and sites.