2.4 Imaging Interferometry of Live Cells
In addition to nanomechanical measurements with nanomirrors, we directly observed mammalian cells with the optical profiler, using no staining or other labeling technique. Imaging live cells required that we construct a special reference cell that matched exactly the dispersion of the liquid cell media, as discussed above. We also constructed a live cell perfusion chamber with a fixed viewing window so that the dimensions of the test path and the compensating cell were identical. This perfusion chamber functions much like a conventional Petri dish to grow and sustain the cell during observation. Fig. 9 shows a phase scanning interferometric image of live NIH 3T3 mouse fibroblast cells taken with the apparatus. The image shows considerable detail of the cell membrane, including intra-cellular organelles.
Fig. 9. Live NIH 3T3 mouse fibroblast cells observed by the optical profiler.
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