Reflection interference contrast microscopy

The interest in vesicles as models for cell biomembranes has led to much work on the interactions within and between lipid layers. The primary contributions to vesicle stability and curvature include those familiar to us already, the electrostatic interactions between charged head groups (Chapter V) and the van der Waals interaction between layers (Chapter VI). An additional force due to thermal fluctuations in membranes produces a steric repulsion between membranes known as the Helfrich or undulation interaction. This force has been quantified by Sackmann and co-workers using reflection interference contrast microscopy to monitor vesicles weakly adhering to a solid substrate [78]. Membrane fluctuation forces may influence the interactions between proteins embedded in them [79]. Finally, in balance with these forces, bending elasticity helps determine shape transitions [80], interactions between inclusions [81], aggregation of membrane junctions [82], and unbinding of pinched membranes [83]. Specific interactions between membrane embedded receptors add an additional complication to biomembrane behavior. These have been stud-... 

Schindl, M., WaUraff, E., Deubzer, B. et al. (1995). Cell-substrate interactions and locomotion of Dictyostelium wild-type and mutants defective in three cytoskeletal proteins a study using quantitative reflection interference contrast microscopy. Biophys. ]. 68, 1177-1190. 

Alternatively to force-based approaches, cell adhesion can be quantified by measuring the intersurface distance between the cell and a planar transparent substrate (Fig. 4.30). Reflection interference contrast microscopy (RICM) is ideally suited for studying cell adhesion characteristics and dynamics in aqueous environment, as it allows for nanometer precise determination of intersurface distances with milliseconds time resolution [62]. It has the added... 

FIGURE 4.30 Optical principle of reflection interference contrast microscopy (RICM). The optical path (a) and the formation of constructive and destractive interference with the resulting reference pattern (b) are depicted on Ref. 61. 

Figure 2.24 Schematic presentation of the direct, as well as inhibition-competition, assay using soft colloidal probes and their analysis via reflection interference contrast microscopy, adapted from Pussak et al. ...

Observation of the Contact Reflection Interference Contrast Microscopy... 

FIGURE 9.24. Principle of the reflection interference contrast microscopy (RICM) technique. 

Many researchers have performed various optical microscopic observations of the surface morphology of ice crystals, such as steps [10, 20-23], height topography [24-31], and QLLs [32, 33], by ordinary bright field microscopy [10, 23, 24], differential interference contrast microscopy [20-22, 25, 29-31, 33], two-beam interferometry [26-28], and laser reflection microscopy [32], However, no one has yet succeeded in proving, by their optical observations, that they could visuahze individual elementary steps, mainly due to the small height of elementary steps. 

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