Abstract
Surface-enhanced Raman scattering (SERS) spectroscopy has been used extensively to study biology, chemistry, and materials. However, a point-by-point SERS mapping is time-consuming, taking minutes to hours for large-scale imaging. Here, we report a wide-field surface-enhanced coherent anti-Stokes Raman scattering (WISE-CARS) microscopy for monitoring nanotags in live cells and label-free detection of metabolic molecules. The WISE-CARS microscope achieves an imaging speed as fast as 120 frames per second for a large field of view of 130 microns X 130 microns. By spectral focusing of femtosecond lasers, a hyperspectral WISE-CARS stack of 120 frames can be acquired with a spectral resolution of 10 cm-1, where over 1 million Raman spectra are parallelly recorded within 0.5 seconds. As applications, we demonstrate time-lapse, 3D WISE-CARS imaging of nanotags in live cells as well as label-free detection of adenine released from S. aureus.
Content

Supplementary material

Video 1. Hyperspectral WISE-CARS imaging of Au NPs substrate.
A hyperspectral SECARS imaging cube of Mpy adsorbed on aggregated Au NPs substrate

Video 3. Hyperspectral WISE-CARS imaging of live cells.
The hyperspectral SECARS spectra of Mpy nanotags in live cells.

Video 2. Movements of nanotags in live cells
60-frame video recorded to show the movements of nanotags inside a live cell during 1 s period

Video 4. 3D WISE-CARS imaging of live cells.
Recorded bright views of T24 cells at different focus planes.

Video 5. 3D WISE-CARS imaging of live cells.
SECARS imaging of Mpy nanotags distributed in T24 cells at different focus planes.

Video 6. 3D projection of nanotags in live cells.
The 3D projection shows the 3D distributions of nanotags in live cells.