4th EucheMs chemistry congress

Poster Session 2
s1229
chem. Listy 106, s257–s1425 (2012)
Poster session 2 - Nanochemistry, Nanotechnology
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SuPrAMoLeCuLAr heLiCAL nAnofiBer
forMAtion froM the SeLf-ASSeMBLy of
CytidyLiC ACid-APPended BoLAAMPhiPhiLe
with di- And tri-CArBoxyLiC ACid
r. iwAurA 1 , M. ohniShi-KAMeyAMA 1
1 National Agriculture and Food Research Organization,
National Food Research Institute, Tsukuba Ibaraki, Japan
Bottom-up approach, which refers to the build-up of
materials from molecular components, has attracted much
attention to many researchers in the field of nanotechnology. In
particular, combination of self-assembly and molecular
recognition, as often seen in biomolecules, is one of the elegant
strategies to make well-defined nanostructures. We chose DNA
as a motif because the excellent property of self-assembly with
molecular recognition ability is already incorporated into DNA
molecules. [1–2] In addition, the production of materials using
renewable bioresources is now a challenging theme in the field of
bottom-up nanotechnology. Herein, the binary self-assembly of
1, 18-cytidylic acid-appended bolaamphiphile (C18C) [3] in which
a 3'-phospholylated cytidine moiety is connected to both ends of
an octadecamethylene chain, and di- or tricarboxylic acids is
reported. Atomic force microscopy (AFM), circular dichroism
(CD), UV absorption, and Fourier-transform infrared (FT-IR)
spectroscopy, and electrospray ionization-Fourier-transform ion
cyclotron resonance (ESI-FTICR) mass spectrometry experiments
revealed the binary self-assembly of C18C and malonic, succinic,
glutaric, or citric acids formed nanofibers through molecular
recognition. Moreover, left-handed helicity was observed in the
nanofiber obtained from the binary self-assembly of C18C and
citric acid (CA) with diameters, lengths, and pitches ca. 6 – 7 nm,
several hundred nm to 5 μm, and ca. 30 – 40 nm, respectively.
Based on the observations, we performed the self-assembly of
C18C in lemon juice containing citric acids, and succeeded in the
formation of the left-handed helical nanofiber by the fusion of
supramolecular chemistry and renewable biomaterials. [4]
references:
1. R. Iwaura et al, Angew. Chem. Int. Ed., 2003, 42, 1009.
2. R. Iwaura et al, Chem. Eur. J., 2009, 15, 3729.
3. R. Iwaura et al, Small, 2010, 6, 1131.
4. R. Iwaura et al, Chem. Commun., accepted.
Keywords: Self-assembly; Nanofibers; Supramolecular
Chemistry; Bolaamphiphiles; Nucleotides;
4 th EucheMs chemistry congress
P - 0 7 3 4
ALiGned Growth of GoLd nAnorodS in PMMA
ChAnneLS: PArALLeL PrePArAtion of
nAnoGAPS
t. JAin 1 , S. LArA-AviLA 2 , y. KervenniC 2 ,
K. Moth-PouLSen 3 , K. norGAArd 1 , S. KuBAtKin 2 ,
t. BJornhoLM 1
1 University of Copenhagen, Nano-Science Center &
Department of Chemistry, Copenhagen, Denmark
2 Chalmers University of Technology, Department of
Microtechnology and Nanoscience, Gothenburg, Sweden
3 Chalmers University of Technology, Department of Chemical
and Biological Engineering, Gothenburg, Sweden
The fabrication of electrode pairs separated by a few
nanometers is a fundamental challenge in nanotechnology. [1, 2]
Nanogaps between metallic electrodes or nanoparticles are
applied within diverse areas such as single-molecule electronics,
plasmonics and spectroscopy. In single-molecule electronics the
goal is to utilize single molecules as electrical components by
understanding how electron transport through molecules is
governed by the chemical structure of a molecule in order to be
able to tailor its specific function. Here, we demonstrate alignment
and positional control of gold nanorods grown in situ on substrates
using a seed-mediated synthetic approach. Alignment control is
obtained by directing the growth of spherical nanoparticle seeds
into nanorods in well-defined poly(methyl methacrylate)
nanochannels. Substrates with prepatterned metallic electrodes
provide an additional handle for the position of the gold nanorods
and yield nanometer-sized gaps between the electrode and
nanorod. The nanogaps are electrically characterized, and to
test the stability of the nanogaps, electronically active
oligo(phenylenevinylene) (OPV) molecules are inserted into a
nanogap junction by solution deposition, which results in an
increase in the electrical conductance of several orders of
magnitude compared to the empty nanogap.
The presented approach is a novel demonstration of
bottom-up device fabrication of multiple nanogap junctions on a
single chip mediated via in situ growth of gold nanorods acting
as nanoelectrodes. 3
references:
1. Jain, T.; Roodbeen, R.; Reeler, N. E. A.; Vosch, T.; Jensen,
K. J.; Bjornholm, T.; Norgaard, K. J. Colloid Interface Sci.
2012, 376, 83-90.
2. Jain, T.; Westerlund, F.; Johnson, E.; Moth-Poulsen, K.;
Bjornholm, T. ACS Nano 2009, 3, 828-34.
3. Jain, T.; Lara-Avila, S.; Kervennic, Y.-V.; Moth-Poulsen, K.;
Norgaard, K.; Kubatkin, S.; Bjornholm, T. ACS Nano
2012, DOI: 10.1021/nn204986y.
Keywords: Nanoparticles; Nanostructures; Molecular
electronics;
AUGUst 26–30, 2012, PrAGUE, cZEcH rEPUbLIc