Scattering polarization by anisotropic biomolecules.

The full polarization properties of anisotropic biomolecule optical scattering are investigated theoretically. By using a simple ellipsoid model of a single biomolecule, the scattering fields and Mueller matrices are derived from fundamental electromagnetism theory. The energy of scattered photons is not necessarily equal to that of the incident laser beam. This theory can be generally applied to the experiments of fluorescence, Raman scattering, and second-harmonic generation. Fitting of a single tetramethylrhodamine-labeled lipid molecule's anisotropic imaging experiment is demonstrated. This theory has provided a fundamental simulation analysis tool of understanding and developing the optical polarimetric sensing science and technology of the anisotropic biomolecules and biomedium. The medium dielectric constant of the model ellipsoid provides a theoretic background for correlating the optical polarization properties of a biomolecule to its microscopic electronic structure.