title: Antiphase dual-color correlation in a reactant-product pair imparts ultrasensitivity in reaction-linked double-photoswitching fluorescence imaging.
abstract: A pair of reversible photochemical reactions correlates their reactant and product specifically, and such a correlation uniquely distinguishes their correlated signal from others that are not linked by this reversible reaction. Here a nanoparticle-shielded fluorophore is photodriven to undergo structural dynamics, alternating between a green-fluorescence state and a red-fluorescence state. As time elapses, the fluorophore can be in either state but not both at the same time. Thus, the red fluorescence is maximized while the green fluorescence is minimized and vice versa. Such an antiphase dual-color (AD) corelationship between the red and green fluorescence maxima as well as between their minima can be exploited to greatly improve the signal-to-noise ratio, thus enhancing the ultimate detection limit. Potential benefits of this correlation include elimination of all interferences originating from single-color dyes and signal amplification of AD photoswitching molecules by orders of magnitude.
authors.affiliation: †Department of Chemistry and Center for Materials Research, Washington State University, Pullman, Washington 99164, United States.
authors.forename: Wei
authors.initials: W
authors.lastname: Wan
authors.affiliation: ‡Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430074, P. R. China.
authors.forename: Ming-Qiang
authors.initials: MQ
authors.lastname: Zhu
authors.affiliation: §School of Chemistry and Chemical Engineering, University of Chinese Academy of Sciences, Beijing 100049, P. R. China.
authors.forename: Zhiyuan
authors.initials: Z
authors.lastname: Tian
authors.affiliation: †Department of Chemistry and Center for Materials Research, Washington State University, Pullman, Washington 99164, United States.
authors.forename: Alexander D Q
authors.initials: AD
authors.lastname: Li