Helix-dependent Spin Filtering through the DNA Duplex
Recent work suggests that electrons can travel through DNA and other chiral molecules in a spin-selective manner, but little is known about the origin of this spin selectivity. Here we describe experiments on magnetized DNA-modified electrodes to explore spin-selective electron transport through hydrated duplex DNA. Our results show that the two spins migrate through duplex DNA with different yield, and that spin selectivity requires charge transport through the DNA duplex. Significantly, shifting the same duplex DNA between right-handed B- and left-handed Z-forms leads to a diode-like switch in spin-selectivity; which spin moves more efficiently through the duplex depends upon the DNA helicity. With DNA, the supramolecular organization of chiral moieties, rather than the chirality of the individual monomers, determines the selectivity in spin, and thus a conformational change can switch the spin selectivity.
© 2016 American Chemical Society. Publication Date (Web): 15 Nov 2016. We are grateful to the NIH (GM61077) and the Moore Foundation for their financial support. TJZ is also an NSF GRFP fellow (DGE-1144469). We thank Dr. Natalie Muren for discussions. We thank John Abendroth, Professor Paul Weiss, Elizabeth O'Brien, and Philip Bartels for providing gold-capped nickel surfaces. The authors declare no competing financial interest.
Accepted Version - jacs_2E6b10538.pdf
Accepted Version - nihms835226.pdf
Supplemental Material - ja6b10538_si_002.pdf