Supplementary Online Materials
Hall Transport of Divalent Metal Ion Modified DNA Lattices
Sreekantha Reddy Dugasani1,a), Keun Woo Lee1,a), Si Joon Kim2,a), Sanghyun Yoo1,
Bramaramba Gnapareddy1, Joohye Jung2, Tae Soo Jung2, Saima Bashar1,
Hyun Jae Kim2,b) and Sung Ha Park1,c)
1
Department of Physics and Sungkyunkwan Advanced Institute of Nanotechnology (SAINT)
Sungkyunkwan University, Suwon 440-746, Korea
2
School of Electrical and Electronic Engineering, Yonsei University, Seoul 120-749, Korea
a)
S. R. Dugasani, K. W. Lee and S. J. Kim contributed equally to this work.
b)
Electronic mail: hjk3@yonsei.ac.kr
c)
Electronic mail: sunghapark@skku.edu
FIG. S1. A schematic sequence diagram of the double-crossover (DX) [DX = (DX1) +
(DX2)] tiles. Each tile consists four strands DX1-1, DX1-2, DX1-3, and DX1-4 for (DX1)
tile and DX2-1, DX2-2, DX2-3, and DX2-4 for (DX2). The complementary sticky end pairs
are shown as Sn and Sn’ in sequence drawings (blue).
Table S1. Sequence pool for the double-crossover (DX) tiles
Strand
Total # of
NTs
DX1-1
DX1-2
DX1-3
DX1-4
DX2-1
DX2-2
DX2-3
DX2-4
26
48
48
26
26
48
48
26
Sequence (5’ to 3’)
TGCTA CTACCGCA CCAGAATG CTAGT
CATTCTGG ACGCCATA AGATAGCA CCTCGACT CATTTGCC TGCGGTAG
CAGTAGCC TGCTATCT TATGGCGT GGCAAATG AGTCGAGG ACGGATCG
CATAC CGATCCGT GGCTACTG TCACT
GTATG GGCAATCC ACAACCGC AGTGA
GCGGTTGT CCAACTTA CCAGATCC ACAAGCCG ACGTTACA GGATTGCC
GCTCTACA GGATCTGG TAAGTTGG TGTAACGT CGGCTTGT CCGTTCGC
TAGCA GCGAACGG TGTAGAGC ACTAG
Table S2. Sticky-ends for the double-crossover (DX) tiles shown in Fig. S1
S1
S2
S3
S4
5’ to 3’
3’ to 5’
TGCTA
CTAGT
TCACT
CATAC
ACGAT
GATCA
AGTGA
GTATG
S1’
S2’
S3’
S4’
FIG. S2. AFM image of DNA lattices without metel ions. The yellow dotted lines in the
AFM image reveals the DNA lattice boundaries. The inset on the AFM image is noisefiltered reconstructed image (scan size 100 × 100 nm2) by fast Fourier transform showing the
clear periodicity of the building blocks.
FIG. S3. AFM images and corresponding thickness profiles of (a) pristine DNA and (b) Cu2+modified DNA lattices under buffer condition. The substrate-assisted growth method was
used to fabricate an extremely thin monolayer of DNA lattices that achieved full coverage
(with proper initial concentration of DX tiles) of O2 plasma-treated substrates. Although the
known diameter of the DNA duplex was ~2 nm, the thicknesses of DNA lattices without and
with metal ion were 1.2  0.2 nm under buffer due to the electrostatic interaction between
intrinsically charged DNA molecules and the O2 plasma-treated silica substrates. It meant
that noticeable thickness changes after metal ion modification were hardly observable due to
the very small ionic radius. In dry state, suppression of the thickness of the DNA lattices
bound on the substrate was more severe (~70%) and the measured thickness of DNA duplex
was 0.6  0.2 nm due to the dehydration as well as the electrostatic interaction (previously
reported by one of our authors, S. H. Park et al., Appl. Phys. Lett. 2006, 89, 033901).