Automated Tracking of Vesicles in Phase Contrast Microscopy Images

We propose an algorithm for automated tracking of the contours of phospholipid vesicles, which can be used to evaluate the power, magnitude and frequency distribution of vesicle contour movements induced by thermal fluctuations. The algorithm was tested on vesicles with different structure composition that were exposed to variable temperature. The results show that the proposed algorithm is fast, robust and reliable, and that the resulting description of vesicle contours enables straightforward spectral analysis of their fluctuations, which can be also used for the determination of other vesicle properties, e.g. the bending rigidity or spontaneous curvature.