Tadao Takada's research while affiliated with University of Hyogo and other places

Publications (76)

Article
Fluorescence imaging uses changes in the fluorescence intensity and emission wavelength to analyze multiple targets simultaneously. To increase the number of targets that can be identified simultaneously, fluorescence blinking can be used as an additional parameter. To understand and eventually control blinking, we used DNA as a platform to elucida...
Article
DNA B−Z transitions play an important role in biological systems and have attracted much attention in DNA nanotechnology. DNA and its analogues have also been used as templates to construct helical chromophore associates with π‐interactions. We prepared DNAs with consecutive non‐nucleoside pyrene residues in the middle of d(CG) repeat sequences. Th...
Article
The molecular arrangement of functional chromophores is essential to construct functional nanomaterials. Synthetic DNA has been used as a structural scaffold to control and construct the molecular assembly. We now describe the formation of artificial DNA/porphyrin complexes where porphyrins working as photoactive molecules were placed at specific l...
Article
Functional nucleic acids with the capability of generating fluorescence in response to hybridization events, microenvironment or structural changes are valuable as structural probes and chemical sensors. We now demonstrate the enzyme-assisted preparation of nucleic acids possessing multiple thiazole orange (TO) dyes and their fluorescent behavior,...
Article
B‐ to Z‐DNA transitions play a crucial role in biological systems and have attracted the interest of researchers for their applications in DNA nanotechnology. DNA and DNA analogs have also been used as templates to construct helical chromophore associations with π‐interactions. In this work, the B‐ to Z‐DNA transition‐induced switching of pyrene in...
Article
The construction of zipper‐like chromophore‐arrays in the major groove of duplex DNA remains a challenge because only a few chromophores for this application have been discovered. To address the challenge, dual‐chromophore labeled DNAs having a self‐complementary sequence were prepared using a solid‐phase, post‐synthetic, copper‐catalyzed, alkyne‐a...
Article
In this report, we describe the circularly polarized luminescence (CPL) of the RNA duplexes having one to four 2′-O-pyrene modified uridines (Upy) and the DNA duplexes having two, four, and six pyrene modified non-nucleosidic linkers (Py). Both the pyrene π-stack arrays formed on the RNA and DNA double helical structures exhibited pyrene excimer fl...
Article
We have demonstrated the rapid electron transfer in homo‐ and hetero‐complexes composed of the parent perylenediimide (PDI, PH) and pyrrolidine‐substituted PDI (PN) in DNA analyzed by steady‐state fluorescence and femtosecond transient absorption measurements. The DNA molecules possessing PH and PN were prepared by our recently developed method usi...
Article
Previously it has been found that one-dimensional chromophore-aggregates of naphthalenediimide (NDI) and bis(2-thienyl)diketopyrrolopyrrole (TDPP) could be constructed using 40-mer oligodeoxythymidines (dT40) as a scaffold. Furthermore, the chromophore-aggregate (NDI-dT40/TDPP-dT40) co-immobilized heterojunction gold electrode exhibits a more effic...
Article
We describe here the formation of a porphyrin (Por) dimer using a DNA duplex as a scaffold and photocurrent generation from electrodes modified with a monolayer of Por-DNA conjugates. The solid-phase click reaction between an azide-porphyrin and oligonucleotide labeled with an ethynyl group on CPG supports was utilized for the conjugation of the Po...
Article
Synthetic small molecules with a binding affinity to mismatched base pairs have been widely studied because of their potential applications in chemotherapeutic drugs and diagnostic tools for the detection of single nucleotide variations. In this paper, a luminescent ligand, a perylenediimide (PO) derivative, which is capable of binding to mismatche...
Article
We describe the synthesis, binding, and electrochemical properties of ferrocene-conjugated oligonucleotides (Fc-oligos). The key step for the preparation of Fc-oligos contains the coupling of vinylferrocene to 5-iododeoxyuridine via Heck reaction. The Fc-conjugated deoxyuridine phosphoramidite was used in the Fc-oligonucleotide synthesis. We show t...
Article
DNA is considered to be a promising biomolecule as a template and scaffold for arranging and organizing functional molecules on the nanoscale. The construction and evaluation of DNAs containing multiple functional molecules that are useful for optoelectronic devices and sensors has been studied. In this paper we report the efficient incorporation o...
Article
Circularly polarized luminescence (CPL) can be observed in pyrene zipper arrays that are helically arranged on RNA duplex. Hybridization of complementary RNA strands having multiple (two ~ five) 2'-O-pyrenylmethyl modified nucleosides, which are separated by one nucleoside from each other, affords RNA duplex with normal thermal stability. The pyren...
Chapter
Chromophores in a π-stacked system show unique photophysical properties, such as energy and charge transfer through the strong electronic coupling interaction between the chromophores. A variety of supramolecular structures to realize efficient light-harvesting and charge conduction properties have been designed and prepared. DNA and RNA are a usef...
Article
Coulomb blockade/staircase phenomena of deoxyribonucleic acid (DNA) molecule have been observed so far. Here, we show a non-Coulomb blockade/staircase phenomenon of holes in a mesoscopic scale λ-DNA, which serves as a channel on SiO2/Si structure. It is considered that the phenomena are due to the penetration of the wave function in the DNA into th...
Article
The syntheses of 2'-O-(pyren-1-ylmethyl)uridine phosphoramidite, 2'-O-(pyren-1-ylmethyl)adenosine phosphoramidite, and multiple pyrene-attached oligo-RNAs are described in this unit. The 2'-O-(pyren-1-ylmethyl)nucleosides are converted into the corresponding 2'-O-(pyren-1-ylmethyl)nucleoside 3'-phosphoramidites, which can be incorporated into the s...
Article
Multichromophore arrays of bis(2-thienyl)diketopyrrolopyrrole (DPP) and naphthalenediimide (NDI) with two Zn(II) -cyclens were constructed using thymidine DNA as a scaffold through the binding of the Zn(II) -cyclens with thymine bases. We demonstrate photocurrent generation in a donor-acceptor heterojunction configuration consisting of the DPP (don...
Article
We describe a simple and convenient method for the preparation of photoresponsive DNA-modified electrodes using primer extension (PEX) reactions. A naphthalimide derivative was used as the photosensitizer that was attached to the C5-position of 2'-deoxyuridine-5'-triphosphate (dUTP(NI)). It has been found that dUTP(NI) is a good substrate for the P...
Article
The charge-transfer process in noncovalent perylenediimide (PDI)/DNA complexes has been investigated by using nanosecond laser flash photolysis (LFP) and photocurrent measurements. The PDI/DNA complexes were prepared by inclusion of cationic PDI molecules into the artificial cavities created inside DNA. The LFP experiments showed that placement of...
Article
Fluorescent nucleic acids were prepared utilizing the polymerase extension (PEX) reaction to incorporate fluorescent molecules. 2`-Deoxyuridine triphosphate (dUTP) derivatives possessing pyrene molecules as fluorophores were synthesized using the aqueous-phase Sonogashira coupling between 5-Iodo-dUTP and acetylene-linked pyrene molecules. The incor...
Article
Bis(2-thienyl)-diketopyrrolopyrrole having two Zn^{II}-cylcens (DPPCy) was synthesized. DPP-aggregates were constructed by self-organization of DPPCy and dT_n-DNAs. In the presence of L-ascorbic acid as an electron sacrifice reagent, the DPP aggregates immobilized on a gold electrode exhibit good anodic photocurrent responses as well as cathodic ph...
Article
We now show that a hydrophobic cavity created within the DNA can work as a scaffold to form a charge transfer (CT) complex composed of naphthalenediimide (NDI) and dialkoxynaphthalene (DAN) derivatives. The formation of the CT complex resulted in stabilization of the duplex structure through stacking interaction, which was comparable to the natural...
Conference Paper
The carrier behavior m DNA was examined using the DNA channel/SiO2/Si gate structure. In this case, electrodes with a gap of 120 nm using a substrate Si was prepared and DNA was fixed between the electrodes. The dID/dVD shows the maximum value at the drain voltage of 0.7 V. This phenomenon relates to the trapped and detrapped electrons in DNA. The...
Article
Here we study the binding behavior of perylenediimide () derivatives to a hydrophobic pocket created inside DNA and their photochemical properties capable of designing a light-up fluorescent sensor for short single-stranded DNA or RNA. The perylenediimide derivative with alkoxy groups () suppressing electron transfer quenching was examined. The bou...
Conference Paper
The carrier behavior in DNA was examined using the DNA channel/SiO2/Si gate structure. The source/drain electrodes with a gap of 120 nm etching a SOI film was prepared and DNA was fixed between the electrodes. The dID/dVD shows the maximum value at the drain voltage of 0.3 V. This phenomenon relates to the trapped and detrapped electrons in DNA. Th...
Article
Bis(2-thienyl)diketopyrrolopyrrole with two Zn(II) -cyclens (ZnCyc-DPP) was designed and synthesized to evaluate the selective binding of Zn(II) -cyclen with thymine base in single-strand DNA as a tool for the construction of a highly ordered multichromophore system on DNAs. Through UV/Vis titrations, gel filtration chromatography, and circular dic...
Article
We now report the photocurrent generation and charge transfer dynamics of stacked perylenediimide (PDI) molecules within a π-stack array of DNA. The cofacially stacked PDI dimer and trimer were found to strongly enhance the photocurrent generation compared to an isolated PDI monomer. Femtosecond time-resolved transient absorption experiments reveal...
Article
DNA molecules possessing multiple ferrocene (Fc) molecules as a redox active probe were prepared by the primer extension (PEX) reaction using a 2'-deoxyuridine-5'-triphosphate derivative in which Fc was connected to the C5-position of the uridine by a diethylene glycol linker. Gold nanoparticles (AuNP) covered with DNA possessing the Fc molecules w...
Article
The charge retention mechanism of the λ-DNA molecules with 400bp (136nm) are examined. The DNA solution was dropped on the Si source and drain electrodes with the gap of 120nm. The change of the refresh characteristics by applying the negative voltage to the gate was measured. As a result, it was found that the electron trap remarkably influenced o...
Article
DNA oligonucleotides possessing naphthalimide (NI) at the C5 position of deoxyuridine through an ethynyl-containing linker have been synthesized. Based on time-resolved laser flash photolysis, we showed that the photo-induced charge transfer occurs between NI at the C-5 position and the guanine base of DNA with almost same efficiency (1.8%) when co...
Article
Small ligand molecules, which can recognize thermodynamically unstable site within DNA, such as mismatch base pair, abasic site, and single-bulge, have attracted much attention because of their potential diagnostics and biological applications. In this paper, we describe the binding of cationic perylenediimide (cPDI) molecules to thymine-containing...
Article
Because of potential applications in nanoscale devices, DNA-mediated charge transfer (CT) has attracted much interest. Through spectroscopic and chemical studies, it has been shown that both positive and negative charges injected into DNA bases can move through DNA over significant distances. The factors affecting to DNA-mediated CT are the nature...
Article
The binding and fluorescence properties of complementary RNA sequences attached to different numbers of pyrenes via one carbon linker at the 2'-O-positions have been investigated. Upon hybridization of the pyrene-modified RNA sequences, the modified RNA duplexes with normal thermal stability are formed, and the pyrene arrays are assembled in an int...
Article
DNA is a unique yet useful material to organize nanoscale molecular arrays along the helix axis. In this study, we demonstrate a useful approach for creating molecular arrays inside a double helical DNA. Our approach is based on a host-guest system. Introducing abasic sites into DNA afforded a hydrophobic cavity that serves as a host. A planar arom...
Article
We discovered the charge retention property of the field-effect transistor (FET) in a Si gate/SiO2/DNA channel structure. The DNA FET with the Si source and drain showed hole conduction, and the drain current was controlled by the gate voltage application. By inserting the refresh process of gate voltage application of −50V between each measurement...
Article
DNA electronic devices were prepared on silicon-based three-terminal electrodes. Both ends of DNA molecules (400 bp long, mixed sequences) were bridged via chemical bonds between the source-drain nanogap (120 nm) electrodes. S-Shaped I-V curves were obtained and the electric current can be modulated by the gate voltage. The DNA molecules act as sem...
Article
DNA oligomers possessing a 2-nitrobenzyl (NB) protected thiol group have been prepared. The photo-remove of the NB to generate a free thiol group in DNA has been analyzed by using reverse-phase HPLC and denaturing gel electrophoresis. The photo-triggered generation of the thiol function in DNA was applicable in the light-initiated ligation of thiol...
Article
π-Stacked naphthalenediimide (NDI) arrays are of interest as charge-transport materials. We have designed and synthesized an NDI derivative with two Zn(II)-cyclens that act as receptors for the thymine base in DNA. UV/Vis and CD spectroscopy, gel filtration, and molecular-modeling studies have shown that the bis(Zn(II)-cyclen)-NDI can be assembled...
Article
Electron transfer (ET) through RNA duplexes possessing 2'-O-pyrenylmethy uridine (Upy) and 5-bromouracil (BrU) as an electron donor and accepter set was investigated. Reductive decomposition of the BrU resulted from the ET over long distances (up to ten AU base pairs) was detected in the RNA conjugates. The RNA mediated ET from the pyrene to BrU sh...
Article
DNA-mediated charge transfer has recently received a substantial attention because of its biological relevance in the DNA damage and DNA repair as well as the potential applications to nanoscale electronic devices. In contrast to the numerous mechanistic studies on oxidative hole transfer (HT) through DNA, our understanding of reductive electron tr...
Article
We describe an approach to the development of a new electronic aptamer-based biosensor for multiprotein targets on a single platform. The multiple protein biosensing involves the co-adsorption of several thiol-terminated capture DNA sequences on a gold surface, along with the hybridization of redox-tagged aptamer to each corresponding capture seque...
Article
We prepared RNA duplexes possessing 2′-O-(1-pyrenylmethyl)adenosine and 5-(4-nitrophenyl)uridine base pairs. In the duplexes, pyrene serves as a photo-excitable electron donor and 5-(4-nitrophenyl)uridine acts as an electron acceptor. The donor–acceptor-modified RNA duplexes showed very weak fluorescence originating from the pyrene monomer and exci...
Article
The DNA base stack provides unique features for the efficient long-range charge transfer. For the purpose of investigating excess electron transfer process through DNA, we developed a new method for fluorescence analysis of excess electron transfer based on reductive cleavage of a disulfide bond and a thiol-specific fluorescent probe. Excess electr...
Article
We synthesized multiple pyrene-modified RNA sequences having two kinds of consecutive sequences, U(Py)U(Py) and A(Py)A(Py), and investigated their duplex formations and the pyrene associations.
Article
Template-directed ligation of oligonucleotides by photochemical reaction has attracted much interest because of its biomedical and synthetic applications. In this study, we developed photoligaton of DNA by using a photoremovable protecting group and thiol-disulfide exchange reaction. A phosphoroamidite of o-nitrobenzyl derivatives were synthesized,...
Article
Deoxyuridine triphosphate derivatives modified with pyrene was synthesized to functionalize DNA with fluorescent molecules based on the template DNA sequence. Incorporation of pyrene-labeled deoxyuridine triphosphates into DNA by DNA polymerase was investigated by using reverse-phase HPLC and polyacrylamide gel electrophoresis. The fluorescent prop...
Article
We describe the long-range excess electron transfer through RNA duplexes consisting of a pyrene electron donor and a nitrobenzene electron acceptor that shows double exponential distance dependence.
Article
RNA molecules with multiple pyrenylmethyl substituents on the 2'-O-sugar residues can form duplexes with complementary RNA sequences without losing thermal stability. In the RNA duplexes, covalently incorporated pyrenes can assemble in a helical manner along the minor grooves of the duplex. These helically assembled pyrene arrays exhibit intense ex...
Article
The DNA base stack provides unique features for the efficient long-range charge transfer. For the purpose of investigating the hole transfer process of individual DNA and the optical readout of DNA information at the single molecule level, we performed single-molecule detection of DNA hole transfer (DNA HT) using single-molecule fluorescence spectr...
Article
(Figure Presented) Got a light? The importance of the relationship between the charge recombination and charge transfer during photocurrent generation through DNA films is described. The photocurrent efficiency for DNA films, in which the charge-transfer and recombination rates were modulated by changing the sequence, was investigated by using the...
Article
DNA charge transfer highly depends on the electronic interaction between base pairs and reflects the difference in the base composition and sequence. For the purpose of investigating the charge transfer process of individual DNA molecules and the optical readout of DNA information at the single-molecule level, we performed single-molecule observati...
Article
Key species: Radical pairs generated by photo-induced electron transfer in synthesized DNA are characterized by time-resolved electron paramagnetic resonance (EPR) spectroscopy. Assuming the B-form for DNA, the observed polarization patterns are reproduced taking into account the spin-correlated radical pair mechanism of the electron spin polarizat...
Article
Long-distance hole transfer via A-hopping over a long A sequence in DNA has been studied by time-resolved transient absorption measurements. DNA modified with naphthalimide (NI) and phenothiazine (PTZ), in which two molecules are separated by a consecutive A sequence, was synthesized to investigate the hole transfer process via A-hopping. After the...
Article
(Figure Presented) Base jumping: A long-lived charge-separated state has been generated in high yield for DNA modified with a diphenylacetylene derivative (DPA) through an adenine (A)-base-hopping mechanism (see diagram). Modulation of the redox properties of the photosensitizer and bridge bases (e.g., by employing a brominated adenine (BrA)) can i...
Article
A kinetic study of the single-step hole transfer in DNA was performed by measuring time-resolved transient absorption. DNA molecules with various sequences were designed and conjugated with naphthalimide (NI) and phenothiazine (PTZ) to investigate the sequence and distance dependence of the single-step hole transfer between guanines (Gs). Hole inje...
Article
A series of naphthalimide (NI)- and 5-bromocytosine ((br)C)-modified oligodeoxynucleotides (ODNs) were prepared, and their lifetimes of the charge-separated states during the photosensitized one-electron oxidation of DNA were measured. Various lifetimes of the charge-separated states were observed depending on the sequence and the incorporation sit...
Article
Mechanism of photo-induced electron transfer and the subsequent hole transfer in DNA has been studied extensively, but so far we are not aware of any reliable report of the observation of the long-distance hole-transfer process. In this article, we demonstrate the results of direct observation for the long-distance hole transfer in double-helical D...
Article
Doubly internally pyrene (Py) modified oligodeoxynucleotides (ODNs) were synthesized, and the formation rates of the Py dimer radical cation (Py2•+) were measured upon one-electron oxidation during pulse radiolysis. The formation of Py2•+ with an optical absorption at 1550 nm (charge resonance band) was observed in the time range of 1 μs to 1 ms af...
Article
Charge transfer in DNA is of current interest because of the involvement of charge transfer in oxidative DNA damage and electronic molecular devices. We have investigated the charge separation process via the consecutive adenine (A)-hopping mechanism using laser flash photolysis of DNA conjugated with naphthaldiimide (NDI) as an electron acceptor a...
Article
The hole transfer causes the long-lived charge-separated state in DNA during the photosensitized one-electron oxidation of DNA. The combination of the transient absorption measurement and DNA damage quantification by HPLC clearly demonstrated that the yield of the DNA damage correlates well with the lifetime of the charge-separated state.
Article
The photochemical mechanism of the napthalimide (NI)-photosensitized one-electron oxidation of oligodeoxynucleotides (ODNs) was discussed. The effects of the electrostatic interaction and repulsion between the NI derivatives and ODN and stacked G bases on the photosensitized one-electron oxidation of ODN were studied by the nanosecond transient abs...
Article
To clarify the hole-transfer mechanism in DNA and the factor controlling the hole-transfer rates, the kinetics of hole transfer in DNA was studied by monitoring the transient absorption of the pyrene (Py) radical cation (Py•+) during the pulse radiolysis of oligodeoxynucleotides (ODNs) conjugated with Py. By analyzing the transient absorption of Py...
Article
The kinetics of hole transfer in DNA by adenine-hopping mechanism was investigated by the combined pulse radiolysis-laser flash photolysis method. The hole transfer from Ptz*+* to oxG across the (A)n-bridge preceded by the A-hopping mechanism and the weak distance-dependent hole transfer with the rates faster than 108 s-1 over the distance range of...
Article
Hole transfer process in ODNs conjugated with two organic molecules, pyrene (Py) and phenothiazine (Ptz) was investigated with the pulse radiolysis measurements. Monitoring the transient absorption of Py+ and Ptz+, it was shown that the hole transfer rate was dependent on the distance and sequence between Py and Ptz.
Article
The effects of methyl and bromo groups at C5 of C on the one-electron oxidation rate of G, and on the hole transfer rate in DNA have been investigated. The rates of one-electron oxidation of G and hole transfer from Py+ to 8-oxo-7,8-dihydroguanine were suppressed and enhanced by introducing bromo and methyl groups, respectively, on the C at the com...
Article
The hole transfer through DNA was monitored by the transient absorption of radical cation of phenothiazine (Ptz+). The occurrence of hole transfer from G+ generated in DNA to Ptz was observed in the time range of 100 μs. The hole transfer to Ptz was significantly suppressed by introducing oxG as a hole trap in DNA, and the trapping reaction of oxG+...

Citations

... It has been proposed that hydrophobic attractions between PDI moieties play an important role in stabilizing the folded structure at high temperatures, and that the DNA loops do not contribute to the inverse-temperature folding behavior [71]. Furthermore, it was reported that the parent PDI and pyrrolidine-substituted PDI pair are comparable to the natural base pairs and can lead to the formation of stable and stacked heterodimers within DNA duplexes [72]. These modified DNA duplexes were obtained by using enzymatically generated abasic sites that create reactive sites for PDI. ...
... Chiral ions or ionic molecules are attractive owing to their asymmetric catalytic activity, 1-4 enantioselectivity, 5 or their chiroptical properties. 6,7 Chiral co-crystallization, 8 chiral molecular assemblies, [9][10][11][12][13][14][15] or confinement of achiral ions in chiral cyclodextrins 16 can be used to induce chiroptical properties to achiral ions or molecules and/or enhancing chiral signals with promising advantages such as (1) tunability of the chiral properties, (2) versatility of [This article is part of the Special Issue: Chirality in France.] choices of chromophores (molecules, ions particles, etc.), and (3) transparency of solutions in the UV-vis region due to the nanometric size of the assemblies. ...
... The 5-(4-azidophenyl)porphyrin P82 was also used to form porphyrin-DNA conjugates [68]. The conjugates were prepared by solid-phase click reaction between the azide P82 and oligodeoxynucleotides with an ethynyl group on controlled pore glass support (Scheme 29). ...
... On the other hand, the emission of pyrene was demonstrated to be strongly depended on their environment. When pyrenes were spatially confined into well-organized hosts like cyclodextrins, [11] oligopeptides [12] and RNA duplexes, [13] strong CPEE with g lum values up to an order of 10 À2 could be obtained. Recently, six pyrenyl moieties were restricted in a quaternaphthyl-based axially chiral skeleton and high g lum values were also achieved. ...
... Owing to these unique predictable properties, the 2′-O-(pyrene-1-yl)methyl-modified nucleotide monomers have been used as components of highly sensitive probes in a number of fluorescent approaches to RNA detection [36][37][38][39][40][41][42][43][44][45]47], as SNP-discriminating RNA-specific fluorescent probes [48,49], as key components in highly-fluorescent pyrene π-stack arrays on RNA (Figure 2b) (Section 2.3.6) [46,[50][51][52][53][54][55], and also as intercalating units efficiently stabilizing DNA:DNA duplexes (Section 3.2) [56][57][58][59][60][61][62][63]. The properties and applications of the oligonucleotides comprising 2′-O-(pyren-1yl)methylribonucleotides monomers have been discussed in detail in the just published review [64]. ...
... Although this structural motif does not sensibly perturb the adhesion capacity of the TT loops, it does modify the overall hydration properties of the aptamer by increasing its hydrophobic character. 50,52 In this respect, the present crystal data are particularly rich of useful information regarding the properties of this TBA variant, which can throw light on its behavior in solution. In the solid phase a, which hosts only the binary complex, the solvent content is considerably high, i.e., almost double with respect to the other crystal forms ( Table 1). ...
... Metal-base pair interaction-driven molecular architectonics are one of the major alternatives to hydrogen bonding (WC and non-WC)-supported base pair interactions for the development of functional DNA nanoarchitectures. Nakamura and co-workers reported the construction of metal-ssDNA coassembly systems wherein Zn(II)-bis(cyclen)-conjugated NDI and diketopyrrolopyrrole (DPP)-based multichromophore units were used for mutual templating of short oligonucleotides (Figure 7a) [84]. In their previous reports, Zn(II)-bis(cyclen)- conjugated NDI were shown to guide the formation of multichromophore arrays via binding with dT n , and the lengths of the multichromophore arrays were found to be dependent on the dT n chain length and temperature [85]. ...
... If hydrophobic micro-domains of DAHBCs were formed in an aqueous solution, pyrene molecules preferably located inside or closed to the hydrophobic micro-domains rather than the aqueous phase, resulting in different photophysical characteristics [37]. Intensity ratio (I 373 /I 384 ) was low when pyrene was mixed with hydrophilic environment, whereas it increased substantially when pyrene was located into hydrophobic micro-domain [38]. The fluorescence emission spectra of pyrene incorporated into self-aggregates of DAHBCs were obtained in various concentrations. ...
... [4,[19][20][21][22] DNA has been used as a supramolecular scaffold for the construction of distinct arrays of aromatic dyes. [7,[23][24][25][26][27][28][29][30][31][32][33] The formation of chromophore segments that are welldefined with regard to the number and kind of the components is readily controlled by hybridization of complementary strands. Recently, we reported the DNA-guided assembly of homo-and hetero-multichromophores. ...
... The interested reader is directed to an investigation of the photoconductivity and charge separation dynamics of the dS2 systems. 169 As shown in Figure 13A, have been found to bind G-quadruplexes, supramolecular structures that form within telomeric and other oncogenic promoter sequences of DNA. [172][173][174] The binding has also been found to be pH dependent, with monomeric species binding in low pH environments to both DNA duplexes and G-quadruplexes, and selective binding of G-quadruplexes with higher order aggregation at higher pH. ...