Microscope laser light scattering spectroscopy of single biological cells.

A microscope laser light scattering setup was developed, allowing us to do intensity autocorrelation spectroscopy on the light scattered from a volume as small as (2 micron)3. This non-invasive technique makes cytoplasmic studies possible inside single live biological cells. The effect of osmotic swelling and shrinking on the diffusion coefficient of hemoglobin inside intact red blood cells is shown as an illustrative example of the applicability and sensitivity of this new experimental method.