posted on 2022-01-26, 14:44authored byAihui Sun, Yaoyao Ji, Yaxi Li, Wenhui Xie, Zhihe Liu, Tingting Li, Tian Jin, Weizhi Qi, Kai Li, Changfeng Wu, Lei Xi
Photoacoustic imaging (PAI) has been
widely used in multiscale
and multicontrast imaging of biological structures and functions.
Optical resolution photoacoustic microscopy (OR-PAM), an emerging
submodality of PAI, features high lateral resolution and rich optical
contrast, indicating great potential in visualizing cellular and subcellular
structures. However, three-dimensional (3D) imaging of subcellular
structures using OR-PAM has remained a challenge due to the limited
axial resolution. In this study, we propose a multicolor 3D photoacoustic
microscopy with high lateral/axial resolutions of 0.42/2 and 0.5/2.5
μm at 532 and 780 nm excitation, respectively. Owing to the
significantly increased axial resolution, we could visualize the volumetric
subcellular structures of melanoma cells using intrinsic contrast.
In addition, we carried out multicolor imaging of labeled microtubules/clathrin-coated
pits (CCP) and microtubules/mitochondria, respectively, with one scanning
by using two different excitation wavelengths. The internal connections
between different subcellular structures are revealed by quantitatively
comparing the spatial distributions of microtubules/CCP and microtubules/mitochondria
in a single cell. Current results suggest that the proposed OR-PAM
may serve as an efficient tool for subcellular and cytophysiological
studies.