A novel approach for miRNA assay using a cationic polythiophene derivative, poly[3-(3’-N,N,N-trie... more A novel approach for miRNA assay using a cationic polythiophene derivative, poly[3-(3’-N,N,N-triethylamino-1’-propyloxy)-4-methyl-2,5-thiophene hydrobromide] (PT), immobilized on a quartz resonator is proposed. The cationic PT enables capturing of all RNA sequences in the sample matrix via electrostatic interactions, resulting in the formation of PT–RNA duplex structures on quartz resonators. Biotinylated peptide nucleic acid (b-PNA) sequences are subsequently utilized for the RNA assay, upon monitoring the PT–RNA–b-PNA triplex formation. Signal amplification is achieved by anchoring avidin coated nanoparticles to b-PNA in order to yield responses at clinically relevant concentration regimes. Unlike conventional nucleic acid assay methodologies that usually quantify a specific sequence of RNA, the proposed approach enables the assay of any RNA sequence in the sample matrix upon hybridization with a PNA sequence complementary to the RNA of interest. As an illustration, successful detection of mir21, (a miRNA sequence associated with lung cancer) is demonstrated with a limit of detection of 400 pM. Furthermore, precise quantification of mir21 in plasma samples is demonstrated without requiring PCR and sophisticated instrumentation.
Due to their inherently dynamic natures and fascinating photoluminescent/photoelectronic
properti... more Due to their inherently dynamic natures and fascinating photoluminescent/photoelectronic properties, coordination compounds of metal ions and conjugated terpyridine ligands have attracted considerable attention as functional materials for a variety of potential applications. In this feature article, a summary of recent work toward the development of one- (1D), two- (2D), and three-dimensional (3D) supramolecular polymers, networks, and metallomacrocycles based on zinc metal ion coordination of conjugated units bearing terpyridine ligands is presented, and it is shown how it fi ts within the overall framework of work in this fi eld. Here, a sequential study from terpyridines as basic building blocks to their zinc-coordinated supramolecular 1D polymers, 2D macrocycles, and 2D and 3D networks is developed. These networks are compared with respect to their thermal stabilities, molecular organization, and linear and nonlinear optical properties. This work opens new prospects for the development of supramolecular chemistry of terpyridines and other transition metal ions, and also their application in future optoelectronic devices.
The synthesis of linear and trigonal terpyridine bearing molecules (tpys) and their self-assembly... more The synthesis of linear and trigonal terpyridine bearing molecules (tpys) and their self-assembly to form novel extended self-assembled 2D networks of trigonal tpys with linear tpys through zinc metal ion (Zn 2+ ) co-ordination is reported. The resulting Zn 2+ co-ordination networks have been characterized by means of X-ray photoelectron spectroscopy (XPS), small angle X-ray scattering (SAXS), BET, and photophysical methods. The presence of some short range order in these networks has been shown by the SAXS results and these results have been analyzed with the help of molecular modelling studies.
Wavelength dependence of optical nonlinearity of terpyridine-based Zn(II)-coordinated rigid linea... more Wavelength dependence of optical nonlinearity of terpyridine-based Zn(II)-coordinated rigid linear polymers APL: Org. Electron. Photonics 5, 253 Antenna-enhanced infrared near-field nanospectroscopy of a polymer Appl. Phys. Lett. 101, 193105 (2012) Propagating surface plasmon resonances in two-dimensional patterned gold-grating templates and surface enhanced Raman scattering J. Appl. Phys. 112, 044314 Glycine phases formed from frozen aqueous solutions: Revisited JCP: BioChem. Phys. 6, 08B611 Additional information on Appl. Phys. Lett.
We report here on the synthesis and self-assembly of four star-shaped trigonal 1,3,5-tris-(1,1bip... more We report here on the synthesis and self-assembly of four star-shaped trigonal 1,3,5-tris-(1,1biphenyl-4-yl)-benzene (TBB) derivatives substituted by different functional groups on the terminal positions of the three arms of the molecule: COOCH 3 (1), COOH (2), NH 2 (3), and CN (4). Selfassembly of the triester TBB 1 and tricyano TBB 4 compounds is investigated at the liquid/graphite interface using scanning tunneling microscopy (STM). When deposited from 1-phenyloctane as the solvent the triester TBB 1 first forms a chiral open network (Phase I) which does not evolve with time. In turn, when deposited from tetrahydronaphthalene, TBB 1 also forms a chiral open network but with different lattice parameters as compared to Phase I and with solvent molecules co-adsorbed inside the nanopores (Phase II). In tetrahydronaphthalene, the initial nanoporous structure of TBB 1 (Phase II) progressively evolves into a chiral close-packed row-like structure where molecules are associated two-by-two in a head-to-tail fashion to form pairs (Phase III). Finally, when deposited from 1-phenyloctane the tricyano TBB 4 only forms short-range ordering with an open honeycomb structure and a close-packed row-like structure coexisting on the surface. { Electronic supplementary information (ESI) available: 1 H NMR spectra of TBB 1-4; 13 C-NMR spectra of TBB 3; MALDI TOF Mass Spectra of TBB 2,3; TGA and DSC of TBB 3; UV-visible absorption and emission spectra of TBB 1-4. See
A novel approach for miRNA assay using a cationic polythiophene derivative, poly[3-(3’-N,N,N-trie... more A novel approach for miRNA assay using a cationic polythiophene derivative, poly[3-(3’-N,N,N-triethylamino-1’-propyloxy)-4-methyl-2,5-thiophene hydrobromide] (PT), immobilized on a quartz resonator is proposed. The cationic PT enables capturing of all RNA sequences in the sample matrix via electrostatic interactions, resulting in the formation of PT–RNA duplex structures on quartz resonators. Biotinylated peptide nucleic acid (b-PNA) sequences are subsequently utilized for the RNA assay, upon monitoring the PT–RNA–b-PNA triplex formation. Signal amplification is achieved by anchoring avidin coated nanoparticles to b-PNA in order to yield responses at clinically relevant concentration regimes. Unlike conventional nucleic acid assay methodologies that usually quantify a specific sequence of RNA, the proposed approach enables the assay of any RNA sequence in the sample matrix upon hybridization with a PNA sequence complementary to the RNA of interest. As an illustration, successful detection of mir21, (a miRNA sequence associated with lung cancer) is demonstrated with a limit of detection of 400 pM. Furthermore, precise quantification of mir21 in plasma samples is demonstrated without requiring PCR and sophisticated instrumentation.
Due to their inherently dynamic natures and fascinating photoluminescent/photoelectronic
properti... more Due to their inherently dynamic natures and fascinating photoluminescent/photoelectronic properties, coordination compounds of metal ions and conjugated terpyridine ligands have attracted considerable attention as functional materials for a variety of potential applications. In this feature article, a summary of recent work toward the development of one- (1D), two- (2D), and three-dimensional (3D) supramolecular polymers, networks, and metallomacrocycles based on zinc metal ion coordination of conjugated units bearing terpyridine ligands is presented, and it is shown how it fi ts within the overall framework of work in this fi eld. Here, a sequential study from terpyridines as basic building blocks to their zinc-coordinated supramolecular 1D polymers, 2D macrocycles, and 2D and 3D networks is developed. These networks are compared with respect to their thermal stabilities, molecular organization, and linear and nonlinear optical properties. This work opens new prospects for the development of supramolecular chemistry of terpyridines and other transition metal ions, and also their application in future optoelectronic devices.
The synthesis of linear and trigonal terpyridine bearing molecules (tpys) and their self-assembly... more The synthesis of linear and trigonal terpyridine bearing molecules (tpys) and their self-assembly to form novel extended self-assembled 2D networks of trigonal tpys with linear tpys through zinc metal ion (Zn 2+ ) co-ordination is reported. The resulting Zn 2+ co-ordination networks have been characterized by means of X-ray photoelectron spectroscopy (XPS), small angle X-ray scattering (SAXS), BET, and photophysical methods. The presence of some short range order in these networks has been shown by the SAXS results and these results have been analyzed with the help of molecular modelling studies.
Wavelength dependence of optical nonlinearity of terpyridine-based Zn(II)-coordinated rigid linea... more Wavelength dependence of optical nonlinearity of terpyridine-based Zn(II)-coordinated rigid linear polymers APL: Org. Electron. Photonics 5, 253 Antenna-enhanced infrared near-field nanospectroscopy of a polymer Appl. Phys. Lett. 101, 193105 (2012) Propagating surface plasmon resonances in two-dimensional patterned gold-grating templates and surface enhanced Raman scattering J. Appl. Phys. 112, 044314 Glycine phases formed from frozen aqueous solutions: Revisited JCP: BioChem. Phys. 6, 08B611 Additional information on Appl. Phys. Lett.
We report here on the synthesis and self-assembly of four star-shaped trigonal 1,3,5-tris-(1,1bip... more We report here on the synthesis and self-assembly of four star-shaped trigonal 1,3,5-tris-(1,1biphenyl-4-yl)-benzene (TBB) derivatives substituted by different functional groups on the terminal positions of the three arms of the molecule: COOCH 3 (1), COOH (2), NH 2 (3), and CN (4). Selfassembly of the triester TBB 1 and tricyano TBB 4 compounds is investigated at the liquid/graphite interface using scanning tunneling microscopy (STM). When deposited from 1-phenyloctane as the solvent the triester TBB 1 first forms a chiral open network (Phase I) which does not evolve with time. In turn, when deposited from tetrahydronaphthalene, TBB 1 also forms a chiral open network but with different lattice parameters as compared to Phase I and with solvent molecules co-adsorbed inside the nanopores (Phase II). In tetrahydronaphthalene, the initial nanoporous structure of TBB 1 (Phase II) progressively evolves into a chiral close-packed row-like structure where molecules are associated two-by-two in a head-to-tail fashion to form pairs (Phase III). Finally, when deposited from 1-phenyloctane the tricyano TBB 4 only forms short-range ordering with an open honeycomb structure and a close-packed row-like structure coexisting on the surface. { Electronic supplementary information (ESI) available: 1 H NMR spectra of TBB 1-4; 13 C-NMR spectra of TBB 3; MALDI TOF Mass Spectra of TBB 2,3; TGA and DSC of TBB 3; UV-visible absorption and emission spectra of TBB 1-4. See
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Papers by DEEPA RAJWAR
hydrobromide] (PT), immobilized on a quartz resonator is
proposed. The cationic PT enables capturing of all RNA sequences in the sample matrix via electrostatic
interactions, resulting in the formation of PT–RNA duplex structures on quartz resonators. Biotinylated
peptide nucleic acid (b-PNA) sequences are subsequently utilized for the RNA assay, upon monitoring the
PT–RNA–b-PNA triplex formation. Signal amplification is achieved by anchoring avidin coated nanoparticles
to b-PNA in order to yield responses at clinically relevant concentration regimes. Unlike conventional
nucleic acid assay methodologies that usually quantify a specific sequence of RNA, the proposed
approach enables the assay of any RNA sequence in the sample matrix upon hybridization with a
PNA sequence complementary to the RNA of interest. As an illustration, successful detection of mir21,
(a miRNA sequence associated with lung cancer) is demonstrated with a limit of detection of 400 pM.
Furthermore, precise quantification of mir21 in plasma samples is demonstrated without requiring PCR
and sophisticated instrumentation.
properties, coordination compounds of metal ions and conjugated terpyridine ligands have
attracted considerable attention as functional materials for a variety of potential applications.
In this feature article, a summary of recent work toward the development of one- (1D),
two- (2D), and three-dimensional (3D) supramolecular polymers, networks, and metallomacrocycles
based on zinc metal ion coordination of conjugated units bearing terpyridine ligands
is presented, and it is shown how it fi ts within the overall framework of work in this fi eld.
Here, a sequential study from terpyridines as basic building
blocks to their zinc-coordinated supramolecular 1D polymers,
2D macrocycles, and 2D and 3D networks is developed. These
networks are compared with respect to their thermal stabilities,
molecular organization, and linear and nonlinear optical
properties. This work opens new prospects for the development
of supramolecular chemistry of terpyridines and other
transition metal ions, and also their application in future
optoelectronic devices.
hydrobromide] (PT), immobilized on a quartz resonator is
proposed. The cationic PT enables capturing of all RNA sequences in the sample matrix via electrostatic
interactions, resulting in the formation of PT–RNA duplex structures on quartz resonators. Biotinylated
peptide nucleic acid (b-PNA) sequences are subsequently utilized for the RNA assay, upon monitoring the
PT–RNA–b-PNA triplex formation. Signal amplification is achieved by anchoring avidin coated nanoparticles
to b-PNA in order to yield responses at clinically relevant concentration regimes. Unlike conventional
nucleic acid assay methodologies that usually quantify a specific sequence of RNA, the proposed
approach enables the assay of any RNA sequence in the sample matrix upon hybridization with a
PNA sequence complementary to the RNA of interest. As an illustration, successful detection of mir21,
(a miRNA sequence associated with lung cancer) is demonstrated with a limit of detection of 400 pM.
Furthermore, precise quantification of mir21 in plasma samples is demonstrated without requiring PCR
and sophisticated instrumentation.
properties, coordination compounds of metal ions and conjugated terpyridine ligands have
attracted considerable attention as functional materials for a variety of potential applications.
In this feature article, a summary of recent work toward the development of one- (1D),
two- (2D), and three-dimensional (3D) supramolecular polymers, networks, and metallomacrocycles
based on zinc metal ion coordination of conjugated units bearing terpyridine ligands
is presented, and it is shown how it fi ts within the overall framework of work in this fi eld.
Here, a sequential study from terpyridines as basic building
blocks to their zinc-coordinated supramolecular 1D polymers,
2D macrocycles, and 2D and 3D networks is developed. These
networks are compared with respect to their thermal stabilities,
molecular organization, and linear and nonlinear optical
properties. This work opens new prospects for the development
of supramolecular chemistry of terpyridines and other
transition metal ions, and also their application in future
optoelectronic devices.