Abstract:
:Chiral objects which scatter and absorb preferentially left versus right circularly polarized light give rise to bright-field circular dichroism (CD) images containing contributions from both these two phenomena. These contributions are separated and characterized mathematically, and the effect of the dimensions of the chiral object on their relative magnitude is discussed. CD images of the long-range chiral organization of the thylakoid membranes in chloroplasts are obtained at two different wavelengths to illustrate the diverse wavelength dependence of the preferential absorption and scattering contributions to the images. The bright field CD images not only depend on the magnitude and sign of the preferential scattering and preferential absorption contributions, but also on the numerical aperture of the lens used. This dependence is obtained formally and a method to extract the angle dependent preferential scattering contributions to the images is presented. The validity of this method is confirmed experimentally.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Finzi L,Ulibarri L,Bustamante Cdoi
10.1016/S0006-3495(91)82334-7subject
Has Abstractpub_date
1991-06-01 00:00:00pages
1183-93issue
6eissn
0006-3495issn
1542-0086pii
S0006-3495(91)82334-7journal_volume
59pub_type
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