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We evaluated the elasticity of live tissues of zebrafish embryos using label‐free optical elastography. We employed a pair of custom‐built elastic microcantilevers to gently compress a zebrafish embryo and used optical‐tracking analysis to obtain the induced internal strain. We then built a finite element method (FEM) model and matched the strain with the optical analysis. The elastic moduli were found by minimizing the root‐mean‐square errors between the optical and FEM analyses. We evaluated the average elastic moduli of a developing somite, the overlying ectoderm, and the underlying yolk of seven zebrafish embryos during the early somitogenesis stages. The estimation results showed that the average elastic modulus of the somite increased from 150 to 700 Pa between 4‐ and 8‐somite stages, while those of the ectoderm and the yolk stayed between 100 and 200 Pa, and they did not show significant changes. The result matches well with the developmental process of somitogenesis reported in the literature. This is among the first attempts to quantify spatially‐resolved elasticity of embryonic tissues from optical elastography. [ABSTRACT FROM AUTHOR]

We report the development of a multichannel microscopy for whole‐slide multiplane, multispectral and phase imaging. We use trinocular heads to split the beam path into 6 independent channels and employ a camera array for parallel data acquisition, achieving a maximum data throughput of approximately 1 gigapixel per second. To perform single‐frame rapid autofocusing, we place 2 near‐infrared light‐emitting diodes (LEDs) at the back focal plane of the condenser lens to illuminate the sample from 2 different incident angles. A hot mirror is used to direct the near‐infrared light to an autofocusing camera. For multiplane whole‐slide imaging (WSI), we acquire 6 different focal planes of a thick specimen simultaneously. For multispectral WSI, we relay the 6 independent image planes to the same focal position and simultaneously acquire information at 6 spectral bands. For whole‐slide phase imaging, we acquire images at 3 focal positions simultaneously and use the transport‐of‐intensity equation to recover the phase information. We also provide an open‐source design to further increase the number of channels from 6 to 15. The reported platform provides a simple solution for multiplexed fluorescence imaging and multimodal WSI. Acquiring an instant focal stack without z‐scanning may also enable fast 3‐dimensional dynamic tracking of various biological samples. [ABSTRACT FROM AUTHOR]