Article

Doppler flow imaging of cytoplasmic streaming using spectral domain phase microscopy.

Duke University, Department of Biomedical Engineering, Durham, North Carolina 27708, USA.
Journal of Biomedical Optics (Impact Factor: 2.75). 01/2006; 11(2):024014. DOI: 10.1117/1.2193167
Source: PubMed

ABSTRACT Spectral domain phase microscopy (SDPM) is a function extension of spectral domain optical coherence tomography. SDPM achieves exquisite levels of phase stability by employing common-path interferometry. We discuss the theory and limitations of Doppler flow imaging using SDPM, demonstrate monitoring the thermal contraction of a glass sample with nanometer per second velocity sensitivity, and apply this technique to measurement of cytoplasmic streaming in an Amoeba proteus pseudopod. We observe reversal of cytoplasmic flow induced by extracellular CaCl2, and report results that suggest parabolic flow of cytoplasm in the A. proteus pseudopod.

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    • "The capabilities of MRV have already found application in a range of settings which aid the development and validation of numerical codes or theoretical models, for example the visualization of microfluidics flows (Akpa et al. 2007), the imaging of structure and convection in solidifying mushy layers (Aussillous et al. 2006), bifurcation phenomena in the flow through a sudden expansion in a circular pipe (Mullin et al. 2009) and velocity distributions within a three-dimensional vibro-fluidized bed (Huntley et al. 2007). With sufficient time-averaging, spatial resolutions of 10–100 μm can be achieved, allowing imaging of biological systems on scales just slightly larger than those of typical single cells (Choma et al. 2006). This has allowed measurements at tissue level in a variety of plant systems (Scheenen et al. 2001; Kockenberger et al. 2004; Windt et al. 2006); it is in the uniquely sized internodes of Chara that we can obtain measurements of flows internal to single cells. "
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