Direct circular dichroism spectra measurement of stretching long-strand DNA in a tapering microchannel

This paper reports the direct microchannel circular dichroism (CD) measurement method for analyzing conformational changes and orientations of macromolecules in a microchannel flow. CD is a sensitive probe for secondary structure. For that reason, we apply direct CD measurement for microchannels. Herein, we conducted the direct microchannel CD measurement method by devising an optical system in the sample chamber. Furthermore, using this CD microchannel measurement method, we studied conformational changes and orientations of long-strand DNA in an elongational flow.