Tomographic phase microscopy with 180 degrees rotation of live cells in suspension by holographic optical tweezers

作者：Gilboa Mor Habaza Barak; Roichman Yael; Shaked Natan T^*

来源：Optics Letters, 2015, 40(8): 1881-1884.

DOI：10.1364/OL.40.001881

We present a new tomographic phase microscopy (TPM) approach that allows capturing the three-dimensional refractive index structure of single cells in suspension without labeling, using 180 degrees rotation of the cells. This is obtained by integrating an external off-axis interferometer for wide-field wave front acquisition with holographic optical tweezers (HOTs) for trapping and micro-rotation of the suspended cells. In contrast to existing TPM approaches for cell imaging, our approach does not require anchoring the sample to a rotating stage, nor is it limited in angular range as is the illumination rotation approach. Thus, it allows noninvasive TPM of suspended live cells in a wide angular range. The proposed technique is experimentally demonstrated by capturing the three-dimensional refractive index map of yeast cells, while collecting interferometric projections at an angular range of 180 degrees with 5 degrees steps. The interferometric projections are processed by both the filtered back-projection method and the diffraction theory method. The experimental system is integrated with a spinning disk confocal fluorescent microscope for validation of the label-free TPM results.

• 出版日期2015-4-15