Fig. 2: Photoswitching properties and SRS spectroscopy of asymmetric DAE polyyne. | Nature Communications

Fig. 2: Photoswitching properties and SRS spectroscopy of asymmetric DAE polyyne.

From: Photoswitchable polyynes for multiplexed stimulated Raman scattering microscopy with reversible light control

Fig. 2

a Structure of 2-3-OH in the closed form. b UV-Vis absorption spectra of 2-3-OH in the open (blue) and closed (red) forms. Absorption peaks redshifted from 389 nm to 675 nm upon photo-cyclization. c 1H-NMR spectra of 2-3-OH in the open (blue) and closed (red) forms, showing the upfield shifts in the methyl protons after photo-cyclization. Peaks 1, 2, and 3 of three methyl groups were indicated in a. Photo-conversion yield was quantified by methyl peak integration of two forms. d Reversible photoswitching of 2-3-OH over 25 switching cycles under alternating 405 nm and 640 nm illumination. Absorption at 675 nm was measured for photo-fatigue resistance characterization. e Normalized SRS spectra of 2-3-OH in both the open (blue) and closed (red) forms with a Raman frequency shift of 19 cm−1. f SRS signal ratio of 2c-3-OH over 2o-3-OH measured at 2147 cm−1, with an intensity enhancement of 31.8 ± 0.5 (mean±s.d., n = 5 measurements) upon photoswitching.

Back to article page