Bioinspired optofluidic FRET lasers via DNA scaffolds
Yuze Sun, Siyka I. Shopova, Chung-Shieh Wu, Stephen Arnold, and Xudong
PNAS, 107, 16039-16042(2010).

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∕mm2. 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.