Format

Send to

Choose Destination
Phys Rev Lett. 2014 Jan 10;112(1):014302. Epub 2014 Jan 10.

Photoimprint photoacoustic microscopy for three-dimensional label-free subdiffraction imaging.

Author information

1
Optical Imaging Laboratory, Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, Missouri 63130, USA.

Abstract

Subdiffraction optical microscopy allows the imaging of cellular and subcellular structures with a resolution finer than the diffraction limit. Here, combining the absorption-based photoacoustic effect and intensity-dependent photobleaching effect, we demonstrate a simple method for subdiffraction photoacoustic imaging of both fluorescent and nonfluorescent samples. Our method is based on a double-excitation process, where the first excitation pulse partially and inhomogeneously bleaches the molecules in the diffraction-limited excitation volume, thus biasing the signal contributions from a second excitation pulse striking the same region. The differential signal between the two excitations preserves the signal contribution mostly from the center of the excitation volume, and dramatically sharpens the lateral resolution. Moreover, due to the nonlinear nature of the signal, our method offers an inherent optical sectioning capability, which is lacking in conventional photoacoustic microscopy. By scanning the excitation beam, we performed three-dimensional subdiffraction imaging of varied fluorescent and nonfluorescent species. As any molecules have absorption, this technique has the potential to enable label-free subdiffraction imaging, and can be transferred to other optical imaging modalities or combined with other subdiffraction methods.

PMID:
24483902
PMCID:
PMC3957272
DOI:
10.1103/PhysRevLett.112.014302
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for American Physical Society Icon for PubMed Central
Loading ...
Support Center