title: Tomographic phase microscopy with 180° rotation of live cells in suspension by holographic optical tweezers.
abstract: 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° 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° with 5° 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.
authors: Mor
authors: M
authors: Habaza
authors: Barak
authors: B
authors: Gilboa
authors: Yael
authors: Y
authors: Roichman
authors: Natan T
authors: NT
authors: Shaked
mesh_terms: D002470:Cell Survival; D006696:Holography; D007368:Interferometry; D008853:Microscopy / Q000295:instrumentation / Q000379:methods*; D052898:Optical Tweezers; D012399:Rotation; D012441:Saccharomyces cerevisiae / Q000166:cytology*; D013535:Suspensions; D014054:Tomography
chemical_list: D013535:Suspensions