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Radical chain reactions leading to C-C bond formation are widely used in organic synthesis, and initiation of the radical chain process usually requires thermolabile radical initiators. Recent studies on transition-metal-free cross-coupling reactions between aryl halides and arenes have demonstrated an unprecedented initiation system for radical chain reactions, where the combination of simple organic additives and a base was used in place of conventional radical initiators. Among them, the combination of N,N'-dimethylethylenediamine (DMEDA) and t-BuOK is one of the most efficient and representative reaction systems, and the radical initiation mechanism of this system has attracted considerable research interest. In this study, through the combination of kinetic studies, deuterium labeling experiments, and DFT calculations, the radical initiation mechanism of the diamine-promoted cross-coupling reaction was carefully reinvestigated. In light of the present study, a mechanistic network of radical initiation in the DMEDA/t-BuOK system was revealed, which differs dramatically from the previously realized single radical initiation pathway. In this mechanism, the diamine acts as a hydrogen atom donor and plays a dual role as both "radical amplifier" and "radical regulator" to initiate the radical chain process as well as to control the concentration of reactive radical species. This represents a rare example of a structurally simple molecule playing such a subtle role in the radical chain reaction system. The present study sheds some light on the novel radical initiation mode in transition-metal-free cross-coupling reactions following a base-promoted homolytic aromatic substitution (BHAS) mechanism, and may also help to understand the mechanism of relevant reactions. [ABSTRACT FROM AUTHOR]

A thorough understanding of the antimicrobial mechanisms of graphene materials (GMs) is critical to the manipulation of highly efficient antimicrobial nanomaterials for future biomedical applications. Here we review the most recent studies of GM-mediated antimicrobial properties. This review covers the physicochemical properties of GMs, experimental surroundings, and selected microorganisms as well as the interaction between GMs and selected microorganisms to explore controversial antimicrobial activities. Finally, we rationally analyze the strengths and weaknesses of the proposed mechanisms and provide new insights into the remaining challenges and perspectives for future studies. [ABSTRACT FROM AUTHOR]

The magnetic relaxation dynamics of low-coordinate DyIII and ErIII complexes, namely three-coordinate ones with an equatorially coordinated triangle geometry and five-coordinate ones with a trigonal bipyramidal geometry, have been exploited for the first time. The three-coordinate Er-based complex is the first equatorially coordinated mononuclear Er-based single-molecule magnet (SMM) corroborating that simple models can effectively direct the design of target SMMs incorporating 4f-elements. [ABSTRACT FROM AUTHOR]

We report a new approach to selectively deliver antimicrobials to the sites of bacterial infections by utilizing bacterial toxins to activate drug release from gold nanoparticle-stabilized phospholipid liposomes. The binding of chitosan-modified gold nanoparticles to the surface of liposomes can effectively prevent them from fusing with one another and from undesirable payload release in regular storage or physiological environments. However, once these protected liposomes "see" bacteria that secrete toxins, the toxins will insert into the liposome membranes and form pores, through which the encapsulated therapeutic agents are released. The released drugs subsequently impose antimicrobial effects on the toxin-secreting bacteria. Using methicillin-resistant Staphylococcus aureus (MRSA) as a model bacterium and vancomycin as a model anti-MRSA antibiotic, we demonstrate that the synthesized gold nanoparticle-stabilized liposomes can completely release the encapsulated vancomycin within 24 h in the presence of MRSA bacteria and lead to inhibition of MRSA growth as effective as an equal amount of vancomycin-loaded liposomes (without nanoparticle stabilizers) and free vancomycin. This bacterial toxin enabled drug release from nanoparticle-stabilized liposomes provides a new, safe, and effective approach for the treatment of bacterial infections. This technique can be broadly applied to treat a variety of infections caused by bacteria that secrete pore-forming toxins. [ABSTRACT FROM AUTHOR]

It remains an elusive goal to obtain high performance single-walled carbon-nanotube (SWNT) electronics such as field effect transistors (FETs) composed of single- or few-chirality SWNTs, due to broad distributions in as-grown materials. Much progress has been made by various separation approaches to obtain materials enriched in metal or semiconducting nanotubes or even in single chiralties. However, research in validating SWNT separations by electrical transport measurements and building functional electronic devices has been scarce. Here, we performed length, diameter, and chirality separation of DNA functionalized HiPco SWNTs by chromatography methods, and we characterized the chiralities by photoluminescence excitation spectroscopy, optical absorption spectroscopy, and electrical transport measurements. The use of these combined methods provided deeper insight to the degree of separation than either technique alone. Separation of SWNT5 by chirality and diameter occurred at varying degrees that decreased with increasing tube diameter. This calls for new separation methods capable of metallicity or chirality separation of large diameter SWNTs (in the ~1.5 nm range) needed for high performance nanoelectronics. With most of the separated fractions enriched in semiconducting SWNTs, nanotubes placed in parallel in short-channel (~200 nm) electrical devices fail to produce FETs with high on/off switching, indicating incomplete elimination of metallic species. In rare cases with a certain separated SWNT fraction, we were able to fabricate FET devices composed of small-diameter, chemically separated SWNTs in parallel, with high on-/off-current (Ion/Ioff) ratios up to 105 owing to semiconducting SWNTs with only a few (nm) chiralities in the fraction. This was the first time that chemically separated SWNTs were used for short channel, all-semiconducting SWNT electronics dominant by just a few (n,m)'s. Nevertheless, the results suggest that much improved chemical separation methods are needed to produce nanotube electronics at a large scale. [ABSTRACT FROM AUTHOR]

We report a highly selective chemical interaction between single-walled carbon nanotubes and Triton X-100 according to nanotubes' electronic structure and diameter. The interaction is induced by laser irradiation at power densities down to 10-2 µW/µm² but with photon energies matching those for electronic transition in nanotubes. Our experimental results point to a photon-induced chemical interaction of Triton X-100 with metallic nanotubes below 1.1 nm in diameter and indicate the selectivity being dictated by Fermi electrons and enhanced by curvature-induced strain. [ABSTRACT FROM AUTHOR]

Complex Fe(bpyB)3 (1, bpyB = 5,5′-bis- (dimesitylboranyl)-2,2′-bipyridine) and its reduced species [(18-c-6)K(THF)2]·[Fe(bpyB)3] (2) were synthesized. Their solid state and electronic structures were investigated by single crystal X-ray crystallography, electron paramagnetic resonance and UV-vis spectroscopy, and SQUID measurements. In 1 two bpyB radical anions are fused by a diamagnetic FeII ion, whereas in 2 all three bpyB ligands are in the radical state. Complex 1 possesses an open-shell singlet ground state with a singlet-triplet gap of 0.18 kcal mol-1 and 2 features an open-shell doublet ground state with a doublet-quartet gap of 1.4 kcal mol-1, as determined by SQUID measurements. The unpairedelectrons in 1 and 2 mainly delocalize over the boron atoms and the bipyrdine moieties with negligible spin density at the iron center. Complex 2 represents the first isolable example of boron-based triradicals. [ABSTRACT FROM AUTHOR]

Ever since the axial chiral catalysts were developed for asymmetric reactions with excellent chiral discrimination and high efficiencies, the interest in the supramolecular catalyst has also been extensively investigated. Here, with a hint from the typical molecular catalyst, we developed a series of metal-coordinated nanotube (M-helical nanotube, M-HN) catalysts for asymmetric reactions. The M-HN catalyst was fabricated on the basis of the self-assembly of an l-glutamic acid terminated bolaamphiphile, which formed a single-walled nanotube. On one hand, through the coordination of transition metal ions with the carboxylic acid groups on the nanotube surface, a wide variety of single-walled M-HN catalysts could be fabricated, in which the coordination sites could serve as the catalytic sites. On the other hand, using a slight amount of these catalysts, significant reactivity and enantioselectivity were realized for certain asymmetric reactions under mild conditions. Remarkably, Bi(III)-HN could catalyze the asymmetric Mukaiyama aldol reaction with high enantioselectivity (up to 97% ee) in an aqueous system; Cu(II)-HN catalyzed the asymmetric Diels-Alder reaction with up to 91% ee within 60 min. It was suggested that a synergetic effect of the aligned multicatalytic sites and stereochemical selectivity of the M-HN lead to an excellent catalytic performance. Through this work, we proposed a new concept of a single-walled nanotube as catalyst and showed the first example of nanotube catalysts presenting high reactivity and enantioselectivity that rivaled a chiral molecular catalyst. [ABSTRACT FROM AUTHOR]

The article discusses the generation and reactivity of rhodium azavinyl carbenes from stable and readily available NH-triazoles. The cyclopropanation of styrene with 4-phenyl-NH-triazole is illustrated as well as the scope of the process with respect to olefin and triazole. The study concludes that highly reactive rhodium (II) N-triflyl azavinyl carbenes can be synthesized from NH-1,2,3 triazoles.

The article discusses the study which explores the dynamic disorder and stepwise deactivation of enzymes through a chymotrypsin catalyzed hydrolysis reaction. For the study, the single-molecule fluorescence spectroscopy (SMFS) has been employed in order to prove the existence of fluctuations in the activity of single α-chymotrypsin enzymes. Information about the details of the research process as well as its results is discussed.

The article presents information about a study aimed to develop the Langmuir-Blodgett method to create monolayers of aligned noncovalently functionalized single-walled carbon nanotubes (SWNTs) from organic solvents. A suspension of Hipco SWNTs in 1,2-dichloroethane solutions of poly(m-phenylenevinylene-co-2,5-dioctoxy-p-phenylevinylene) was prepared by sonification, ultracentrifugation and filtration.

The article reports that 1 ,5-disubstituted triazoles can be obtained by a ruthenium-catalyzed cycloaddition of organic azides with several terminal alkynes. It investigates the reaction of benzyl azide with phenylacetylene in the presence of various ruthenium complexes. It suggests that Ru(II) complexes catalyze the formation of 1,2,3-triazoles, with catalytic activity and regioselectivity being a sensitive function of the ligand environment around the ruthenium catalytic center. It reports that in the presence of the acetate complex, Ru(OAc)2 (PPh3)2, the azide was completely consumed, and the 1,4-disubstituted triazole product together with small amounts of dimers and oligomers of phenylacetylene, was formed.

Examines the role of N-edited 2D transferred nuclear overhauser effects on the conformation of an integrin antagonist. Yields of N-labeled peptides after purification with RP-HPLC; Observation of fast exchange between free and bound states on RGD peptide; Excitation of resonances by the QUIET-BIRD-NOESY pulse sequence in 2D-QUIET-HSQC-trNOESY.

Hexakis (4-iodophenyl)-peri-hexabenzocoronene (5), a novel functionalizable mesogenic building block, was prepared by rational multistep synthesis. Although sparingly soluble in common solvents, it can be obtained in pure form and then functionalized via Hagihara-Sonogashira coupling to give a series of highly ordered columnar liquid crystalline molecules 14a-c. The total synthesis involves five 6-fold transformations, all in excellent to near quantitative isolated yields. Their thermotropic liquid crystalline behavior was studied by differential scanning calorimetry (DSC), polarized optical microscopy (POM) and wide-angle X-ray diffraction (WAXD). Compared to the normal alkyl-substituted hexabenzocoronenes (HBCs), 14a-c exhibit more highly ordered columnar mesophases, including three-dimensionally ordered super-structures (helical columnar mesophase). These could arise from additional intracolumnar π-π interactions between, and space-filling requirements introduced by, the rigid-rod side groups. Atomic force microscopy (AFM) revealed self-assembled bundles of columnar aggregates in spin-coated films and isolated several-micron-long nanoribbons composed of a defined number of columns in drop cast films. [ABSTRACT FROM AUTHOR]

A three-dimensional chiral metal formate framework compound, [NH4][Zn(HCOO)3], undergoes a paraelectric-ferro-electric phase transition at 191 K triggered by the disorder-order transition of NH4+ cations within the structure. [ABSTRACT FROM AUTHOR]

The energy difference between a singlet exciton and twice of a triplet exciton, ΔESF, provides the thermodynamic driving force for singlet exciton fission (SF). This work reports a systematic investigation on the effect of ΔESF on SF efficiency of five heteroacenes in their solutions. The low-temperature, near-infrared phosphorescence spectra gave the energy levels of the triplet excitons, allowing us to identify the values of ΔESF, which are -0.58, -0.34, -0.31, -0.32, and -0.34 eV for the thiophene, benzene, pyridine, and two tetrafluorobenzene terminated molecules, respectively. Corresponding SF efficiencies of the five heteroacenes in 0.02 M solutions were determined via femtosecond transient absorption spectroscopy to be 117%, 124%, 140%, 132%, and 135%, respectively. This result reveals that higher ΔESF is not, as commonly expected, always beneficial for higher SF efficiency in solution phase. On the contrary, excessive exoergicity results in reduction of SF efficiency in the heteroacenes due to the promotion of other competitive exciton relaxation pathways. Therefore, it is important to optimize thermodynamic driving force when designing organic materials for high SF efficiency. [ABSTRACT FROM AUTHOR]

Postassembly modification strategy has been successfully employed in the construction of discrete metallosupramolecular assemblies. However, the most known reports have been limited to the simple structural conversion through the easy covalent reactions, thus hindering the development of organometallic functional materials. In this study, we first combined coordination-driven self-assembly and postassembly reversible addition-fragmentation chain-transfer (RAFT) polymerization to produce a new family of star supramolecular polymers containing well-defined metallacycles as cores, which featured typical lower critical solution temperature (LCST) behavior in water because of the existence of poly(N-isopropylacrylamide) (PNIPAAM) moieties. Moreover, the obtained star polymers could further form supramolecular hydrogels cross-linked by discrete hexagonal metallacycles at room temperature without heating-cooling process. Interestingly, the resultant polymeric hydrogels exhibited stimuli-responsive behavior toward temperature and bromide anion as well as self-healing property. We demonstrated that the dynamic nature of Pt-N bonds in the hexagonal metallacycles played an important role in determining the stimuli-responsive and self-healing property of the final soft matters. Thus, merging coordination-driven self-assembly and postassembly polymerization provided a new avenue to the preparation of functional materials containing well-defined, discrete metal-organic assemblies as main scaffolds. [ABSTRACT FROM AUTHOR]

Nano metal oxides are becoming widely used in industrial, commercial and personal products (semiconductors, optics, solar cells, catalysts, paints, cosmetics, sun-cream lotions, etc.). However, the relationship of surface features (exposed planes, defects and chemical functionalities) with physiochemical properties is not well studied primarily due to lack of a simple technique for their characterization. In this study, solid state 31P MAS NMR is used to map surfaces on various ZnO samples with the assistance of trimethylphosphine (TMP) as a chemical probe. As similar to XRD giving structural information on a crystal, it is demonstrated that this new surface-fingerprint technique not only provides qualitative (chemical shift) but also quantitative (peak intensity) information on the concentration and distribution of cations and anions, oxygen vacancies and hydroxyl groups on various facets from a single deconvoluted 31P NMR spectrum. On the basis of this technique, a new mechanism for photocatalytic •OH radical generation from direct surface-OH oxidation is revealed, which has important implications regarding the safety of using nano oxides in personal care products. [ABSTRACT FROM AUTHOR]

In recent past years, investigation of hierarchical self-assembly for constructing artificial functional materials has attracted considerable attention. Discrete metallacycles based on coordination bonds have proven to be valid scaffolds to fabricate various supramolecular polymers or smart soft matter through hierarchical self-assembly. Here, we present the first example of the hierarchical self-assembly of discrete metallacycles by taking advantage of the positive charges of the organoplatinum(II) metallacycle skeleton through multiple electrostatic interactions. Heparin, a sulfated glycosaminoglycan polymer that has been widely used as an anticoagulant drug, was selected to induce hierarchical self-assembly because of the existence of multiple negative charges. To investigate the hierarchical self-assembly process, an aggregation-induced emission (AIE) active moiety, tetra-phenylethylene (TPE), was introduced onto the metallacycle via coordination-driven self-assembly. Photophysical studies revealed that the addition of heparin to the tris-TPE metallacycles solution resulted in dramatic fluorescence enhancement, which supported the aggregation between metallacycle and heparin driven by multiple electrostatic interactions. Moreover, the entangled pearl-necklace networks were obtained through hierarchical self-assembly as detected by SEM, TEM, and LSCM experiments. In particular, single bead-like chains were observed in the AFM and TEM images, which provided direct, visual evidence for the aggregation of positively charged metallacycles and negatively charged heparin. More interestingly, further optical study demonstrated that this TPE-decorated metallacycle could function as a turn-on fluorescent probe for heparin detection with high sensitivity and selectivity. Thus, this research presents the first example of counter polyanion-induced hierarchical self-assembly of discrete metallacycles and provides a "proof-of-principle" method for heparin sensing and binding. [ABSTRACT FROM AUTHOR]

We report an electrochemically switched smart surface for controlled peptide immobilization and conformation control. This dynamic surface is based on self-assembled monolayers (SAMs) containing surface-bound trimethoxybenzene moieties, which can undergo electrochemically modulated surface activation to be stepwisely converted to two catechol derivatives. This new smart surface can be used to realize stepwise immobilization of a peptide, and more importantly, to control peptide conformation on a surface. We demonstrate herein that with one electrochemical activation step, a linear peptide containing an RGD sequence can be attached onto the SAMs. With the subsequence activation step, the attached linear RGD peptide can be converted into cyclic conformation. The SAMs bounded with linear and cyclic RGD exhibit different adhesion behaviors to fibroblasts cells. The reaction procedure can be well-monitored by cyclic voltammetry (CV), electrochemical surface enhanced Raman microscopy (EC-SERS), and X-ray photoelectron spectroscopy (XPS). It is believed this robust smart surface can find wide applications in surface immobilization of bioactive moieties. [ABSTRACT FROM AUTHOR]

Stepwise synthesis of nanosized Pd−Ru heteronuclear metal–organic cages from predesigned redox- and photo-active Ru(II)-metalloligand and naked Pd(II) ion is described. The resulting cage shows rhombododecahedral shape and contains a 5350 Å3 cavity and 12 open windows, facilitating effective trapping of both polar and nonpolar guest molecules. Protection of photosensitive guests against UV radiation is studied. [ABSTRACT FROM AUTHOR]

A self-decoupled porphyrin with a tripodal anchor has been synthesized and deposited on Au(111) using different wet-chemistry methods. Nanoscale electroluminescence from single porphyrin molecules or aggregates on Au(111) has been realized by tunneling electron excitation. The molecular origin of the luminescence is established by the vibrationally resolved fluorescence spectra observed. The rigid tripodal anchor not only acts as a decoupling spacer but also controls the orientation of the molecule. Intense molecular electroluminescence can be obtained from the emission enhancement provided by a good coupling between the molecular transition dipole and the axial nanocavity plasmon. The unipolar performance of the electroluminescence from the designed tripodal molecule suggests that the porphyrin molecule is likely to be excited by the injection of hot electrons, and then the excited state decays radiatively through Franck–Condon π*−π transitions. These results open up a new route to generating electrically driven nanoscale light sources. [ABSTRACT FROM AUTHOR]

A common strategy for preparing tryptophan-derived epidithiodioxopiperazine (ETP) natural products containing a hydroxyl substituent adjacent to a quaternary carbon stereocenter is reported. This strategy is exemplified by enantioselective total syntheses of four heptacyclic ETP natural products—gliocladine C (6), leptosin D (7), T988C (8), and bionectin A (9)—starting with the di-(tert-butoxycarbonyl) derivative 17 of the trioxopiperazine natural product gliocladin C, which is readily available by enantioselective chemical synthesis. In addition, total syntheses of the enantiomer of gliocladine C (ent-6) and gliocladin A (11), the di(methylthio) congener of bionectin A, are reported. These syntheses illustrate a synthetic strategy wherein diversity in the dioxopiperazine unit of ETP natural products is introduced at a late stage in a synthetic sequence. In vitro cytotoxicity of compounds in this series against invasive human prostrate (DU145) and melanoma (A2058) cancer cell lines is described and compared to that of chaetocin A (4). [ABSTRACT FROM AUTHOR]

A family of three-dimensional chiral metal-formate frameworks of [NH4][M(HCOO)3 ] (M = Mn, Fe, Co, Ni, and Zn) displays paraelectric to ferroelectric phase transitions between 191 and 254 K, triggered by disorder-order transitions of NH4+ cations and their displacement within the framework channels, combined with spin-canted antiferromagnetic ordering within 8-30 K for the magnetic members, providing a new class of metal-organic frameworks showing the coexistence of magnetic and electric orderings. [ABSTRACT FROM AUTHOR]

A concise second-generation total synthesis of the fungal derived alkaloid ( + )-gliocladin C ( l l ) in 10 steps and 11% overall yield from isatin is reported. In addition, the epipolythiodioxopiperazine (ETP) natural product ( + )-gliocladine C (6) has been prepared in six steps and 29% yield from the di-(-test-butoxycarbonyl) precursor of 11. The total synthesis of 6 constitutes the first total synthesis of an ETP natural product containing a hydroxyl substituent adjacent to a quaternary carbon stereo-center in the pyrrolidine ring. [ABSTRACT FROM AUTHOR]

Nanomaterials have been actively pursued for biological and medical applications in recent years. Here, we report the synthesis of several new poly(ethylene glycol) grafted branched polymers for functionalization of various nanomaterials including carbon nanotubes, gold nanoparticles (NPs), and gold nanorods (NRs), affording high aqueous solubility and stability for these materials. We synthesize different surfactant polymers based upon poly(γ-glutamic acid) (γPGA) and poly(maleic anhydride-alt-1-octadecene) (PMHC18). We use the abundant free carboxylic acid groups of γPGA for attaching lipophilic species such as pyrene or phospholipid, which bind to nanomaterials via robust physisorption. Additionally, the remaining carboxylic acids on γPGA or the amine-reactive anhydrides of PMHC18 are then PEGylated, providing extended hydrophilic groups, affording polymeric amphiphiles. We show that single-walled carbon nanotubes (SWNTs), Au NPs, and NRs functionalized by the polymers exhibit high stability in aqueous solutions at different pH values, at elevated temperatures, and in serum. Morever, the polymer-coated SWNTs exhibit remarkably long blood circulation (t1/2 = 22.1 h) upon intravenous injection into mice, far exceeding the previous record of 5.4 h. The ultralong blood circulation time suggests greatly delayed clearance of nanomaterials by the reticuloendothelial system (RES) of mice, a highly desired property for in vivo applications of nanomaterials, including imaging and drug delivery. [ABSTRACT FROM AUTHOR]

We demonstrated in this paper the shape-controlled synthesis of Znln2S4, CuInS2, and CuInSe2 nano- and microstructures through a facile solution-based route. One-dimensional Znln2S4 nanotubes and nanoribbons were synthesized by a solvothermal method with pyridine as the solvent, while Znln2S4 solid or hollow microspheres were hydrothermally prepared in the presence of a surfactant such as cetyltrimethylammonium bromide (CTAB) or poly(ethylene glycol) (PEG). The mechanisms related to the phase formation and morphology control of Znln2S4 are proposed and discussed. The UV-vis absorption spectra show that the as-prepared nano- and micromaterials have strong absorption in a wide range from UV to visible light and that their band gaps are somewhat relevant to the size and morphology. The photoluminescence measurements of the Znln2S4 microspheres at room temperature reveal intense excitation at ~575 nm and red emission at ~784 nm. Furthermore, CulnS2 and CulnSe2 with different morphologies such as spheres, platelets, rods, and fishbonelike shapes were also obtained by similar hydrothermal and solvothermal synthesis. [ABSTRACT FROM AUTHOR]

The article presents a study which examines a highly-diastereo-and enantioselective Rh(II)-catalyzed cyclopropanation using azavinyl carbenes 3 which are derived from 1-sulfonyl 1,2,3-triazoles 4. It states that researchers obtained the copper-catalyzed cycloaddition reaction of alkynes with sulfonyl azides. The study discovers a novel and very efficient Rh(II)-catalyzed asymetric cyclopropanation methodology using stable and readily available N-sulfonyl 1,2,3-triazoles as carbene precursors.

We demonstrate a strategy for designing high-performance, ambipolar, acene-based field-effect transistor (FET) materials, which is based on the replacement of C-H moieties by nitrogen atoms in oligoacenes. By using this strategy, two organic semiconductors, 6,13-bis(triisopropylsilylethynyl)anthradipyndine (1) and 8,9,10,11 -tetrafluoro-6, 13-bis(triisopropylsilylethynyl)-1-azapentacene (3), were synthesized and their FET characteristics studied. Both materials exhib high and balanced hole and electron mobilities, 1 having μh and μe of 0.11 and 0.15 cm²/V·s and 3 having μh and μe of 0.08 and 0.09 cm²/V·s, respectively. The successful demonstration of high and balanced ambipolar FET properties from nitrogen-containing oligoacenes opens up new opportunities for designing high-performance ambipolar organic semiconductors. [ABSTRACT FROM AUTHOR]

The article examines the noncovalent functionalization of single-walled carbon nanotubes (SWNT) with poly-T DNA molecules. The functional groups of sufficient density and stability for uniform and conformal atomic layer deposition of high κ dielectrics are deposited on SWNT. The deposition enables the ultimate vertical scaling limit of nanotube field effect transistors.