Light scattering from nucleated biological cells

The light scattered from nucleated biological cells has been investigated by using four different theoretical models: an opaque disk, a homogeneous sphere, an opaque ring, and a coated sphere. By comparing these four models, diffraction at the edges of the cell and the nucleus has been found to be the predominate scattering mechanism for nucleated biological cells at low angles. The scattering patterns of nucleated cells are found to have a fine lobe (high-frequency) structure dependent on whole cell size, and an envelope lobe (low-frequency) structure dependent on relative nucleus size. The models indicate that the present technique for measuring cell size with a single low-angle light detector is highly dependent on the nucleus to cell diameter ratio. Whole cell size is better estimated by the ratio of the outputs from two low-angle detectors