Resonant Electro-optic Imaging for Microscopy at Nanosecond Resolution

TL;DR

This paper introduces a resonant electro-optic method for wide-field fluorescence lifetime microscopy that achieves nanosecond resolution, enabling high-throughput, single-molecule sensitivity, and dynamic process imaging without prior knowledge.

Contribution

The authors develop a resonant electro-optic gating technique that allows fast, wide-field FLIM with single-molecule sensitivity and high temporal resolution, surpassing previous methods.

Findings

Achieved fluorescence lifetime imaging at 39 MHz gating frequency.

Enabled single-molecule FLIM with exposure times under 100 ms.

Demonstrated high photon throughput with over 10^8 photons per frame.

Abstract

We demonstrate an electro-optic wide-field method to enable fluorescence lifetime microscopy (FLIM) with high throughput and single-molecule sensitivity. Resonantly driven Pockels cells are used to efficiently gate images at 39 MHz, allowing fluorescence lifetime to be captured on standard camera sensors. Lifetime imaging of single molecules is enabled in wide-field with exposure times of less than 100 milliseconds. This capability allows combination of wide-field FLIM with single-molecule super-resolution localization microscopy. Fast single-molecule dynamics such as FRET and molecular binding events are captured from wide-field images without prior spatial knowledge. A lifetime sensitivity of 1.9 times the photon shot-noise limit is achieved, and high throughput is shown by acquiring wide-field FLIM images with millisecond exposure and $>10^8$ photons per frame. Resonant electro-optic FLIM allows lifetime contrast in any wide-field microscopy method.