Bioinspired optofluidic FRET lasers via DNA scaffolds

TLDR

Optofluidic dye lasers promise adaptive photonic devices, compact tunable light sources, and micro total analysis systems, yet they are typically directly pumped by tuning the pump laser into the gain medium absorption band. The study demonstrates bioinspired optofluidic dye lasers excited by FRET, using DNA scaffolds to precisely control donor‑acceptor distance, ratio, and spatial configuration. The authors characterize the FRET‑excited lasers’ spectrum, threshold, and energy conversion efficiency, and showcase various DNA scaffold configurations to illustrate the design flexibility of optofluidic lasers. Nearly 100 % energy transfer is maintained regardless of donor/acceptor concentration, enabling efficient lasing at micromolar acceptor levels—over 1,000 times lower than conventional lasers—with a lasing threshold of ~μJ/mm², opening possibilities for intracavity bio/chemical sensing, biocontrolled photonic devices, and biophysics.

Abstract

Optofluidic dye lasers hold great promise for adaptive photonic devices, compact and wavelength-tunable light sources, and micro total analysis systems. To date, however, nearly all those lasers are directly excited by tuning the pump laser into the gain medium absorption band. Here we demonstrate bioinspired optofluidic dye lasers excited by FRET, in which the donor-acceptor distance, ratio, and spatial configuration can be precisely controlled by DNA scaffolds. The characteristics of the FRET lasers such as spectrum, threshold, and energy conversion efficiency are reported. Through DNA scaffolds, nearly 100% energy transfer can be maintained regardless of the donor and acceptor concentration. As a result, efficient FRET lasing is achieved at an unusually low acceptor concentration of micromolar, over 1,000 times lower than that in conventional optofluidic dye lasers. The lasing threshold is on the order of μJ/mm 2 . Various DNA scaffold FRET lasers are demonstrated to illustrate vast possibilities in optofluidic laser designs. Our work opens a door to many researches and applications such as intracavity bio/chemical sensing, biocontrolled photonic devices, and biophysics.