N7-(carboxymethyl)guanine-lithium crystalline complex: a bioinspired solid electrolyte

Electrochemical device with components having direct significance to biological life processes is a potent futuristic strategy for the realization of all-round green and sustainable development. We present here synthesis design, structural analysis and ion transport of a novel solid organic electrolyte (G7Li), a compound reminiscent of ion channels, derived from regioisomeric N7-guanine-carboxylate conjugate and Li-ions. G7Li, with it\u27s in-built supply of Li(+)-ions, exhibited remarkably high lithium-ion transference number (= 0.75) and tunable room temperature ionic conductivity spanning three decades (≈10(-7) to 10(-3) Ω(-1) cm(-1)) as a function of moisture content. The ionic conductivity show a distinct reversible transition around 80-100 °C, from a dual Li(+) and H(+) (<100 °C) to a pure Li(+) conductor (>100 °C). Systematic studies reveal a transition from water-assisted Li-ion transport to Li hopping-like mechanism involving guanine-Li coordination. While as-synthesized G7Li has potential in humidity sensors, the anhydrous G7Li is attractive for rechargeable batteries

Ion Channel-like Crystallographic Signatures in Modified Guanine–Potassium/Sodium Interactions

This communication describes crystallographic details of structures reminiscent of ion channels, formed from regioisomeric N7 and N9 guanine-carboxylate conjugates with potassium/sodium ions and their subsequent STM observations on Au(111) surface. Ion channel-like crystal structures were obtained with the observation of a notable shift in metal ion coordination from carbonyl to carboxylate oxygen. These results are expected to provide insight into competing sites for modified guanine–metal coordination, an entry into guanine-based ion channels and a route toward guanine-functionalized surfaces

G-quartet type self-assembly of guanine functionalized single-walled carbon nanotubes.

The simple strategy of linking guanine to single-walled carbon nanotubes (CNTs) through covalent functionalization permitted generation of the alignment of the nanotubes into lozenges reminiscent of guanine quartets (G-quartets) in the presence of potassium ions as observed by atomic force microscopy.journal articleresearch support, non-u.s. gov't2012 Mar 212012 02 20importe

Double functionalization of carbon nanotubes with purine and pyrimidine derivatives.

Herein, we have developed a synthetic strategy for the covalent double functionalization of single-walled carbon nanotubes (SWCNTs) with a combination of purine-pyrimidine and purine-purine nucleobase systems. The nucleobases were introduced on the sidewall of oxidized SWCNTs through 1,3-dipolar cycloaddition and by amidation of the carboxylic acids located at the tips and defect sites of the nanotubes. The new nanohybrids were characterized by transmission electron microscopy, thermogravimetric analysis, FTIR and Raman spectroscopy, magic-angle spinning NMR spectroscopy, and Kaiser test. The nucleobase/SWCNT conjugates can be envisaged for the modulation of the interactions with nucleic acids by means of base pairing, thereby opening new possibilities in the development of DNA/CNT nanobioconjugates.journal articleresearch support, non-u.s. gov't2013 Jul2013 05 22importe