/pdf/self-assembled-monolayers-of-thiolates-on-metals-as-a-form-1neb0hj3k4.pdf

Self-assembled monolayers of thiolates on metals as a form of nanotechnology.

Two complementary strategies can be used in the fabrication of molecular biomaterials. In the 'top-down' approach, biomaterials are generated by stripping down a complex entity into its component parts (for example, paring a virus particle down to its capsid to form a viral cage). This contrasts with the 'bottom-up' approach, in which materials are assembled molecule by molecule (and in some cases even atom by atom) to produce novel supramolecular architectures. The latter approach is likely to become an integral part of nanomaterials manufacture and requires a deep understanding of individual molecular building blocks and their structures, assembly properties and dynamic behaviors. Two key elements in molecular fabrication are chemical complementarity and structural compatibility, both of which confer the weak and noncovalent interactions that bind building blocks together during self-assembly. Using natural processes as a guide, substantial advances have been achieved at the interface of nanomaterials and biology, including the fabrication of nanofiber materials for three-dimensional cell culture and tissue engineering, the assembly of peptide or protein nanotubes and helical ribbons, the creation of living microlenses, the synthesis of metal nanowires on DNA templates, the fabrication of peptide, protein and lipid scaffolds, the assembly of electronic materials by bacterial phage selection, and the use of radiofrequency to regulate molecular behaviors.

http://users.isr.ist.utl.pt/~sm3/biomedica/tissue-engeneering/Tiss_eng_3.pdf

Fabrication of novel biomaterials through molecular self-assembly.

▪ Abstract Soft lithography, a set of techniques for microfabrication, is based on printing and molding using elastomeric stamps with the patterns of interest in bas-relief. As a technique for fabricating microstructures for biological applications, soft lithography overcomes many of the shortcomings of photolithography. In particular, soft lithography offers the ability to control the molecular structure of surfaces and to pattern the complex molecules relevant to biology, to fabricate channel structures appropriate for microfluidics, and to pattern and manipulate cells. For the relatively large feature sizes used in biology (≥50 μm), production of prototype patterns and structures is convenient, inexpensive, and rapid. Self-assembled monolayers of alkanethiolates on gold are particularly easy to pattern by soft lithography, and they provide exquisite control over surface biochemistry.

/pdf/soft-lithography-in-biology-and-biochemistry-1qiku7qz44.pdf

Soft Lithography in Biology and Biochemistry

Nanosphere lithography (NSL) is an inexpensive, simple to implement, inherently parallel, high throughput, materials general nanofabrication technique capable of producing an unexpectedly large variety of nanoparticle structures and well-ordered 2D nanoparticle arrays. This article describes our recent efforts to broaden the scope of NSL to include strategies for the fabrication of several new nanoparticle structural motifs and their characterization by atomic force microscopy. NSL has also been demonstrated to be well-suited to the synthesis of size-tunable noble metal nanoparticles in the 20−1000 nm range. This characteristic of NSL has been especially valuable for investigating the fascinating richness of behavior manifested in size-dependent nanoparticle optics. The use of localized surface plasmon resonance (LSPR) spectroscopy to probe the size-tunable optical properties of Ag nanoparticles and their sensitivity to the local, external dielectric environment (viz., the nanoenvironment) is discussed in...

Nanosphere Lithography: A Versatile Nanofabrication Tool for Studies of Size-Dependent Nanoparticle Optics

https://is.muni.cz/el/1431/podzim2006/C7780/um/Read/2711172/SAM_str_grwth_ProgSurfSci00_151.pdf

Structure and growth of self-assembling monolayers

A direct-write “dip-pen” nanolithography (DPN) has been developed to deliver collections of molecules in a positive printing mode. An atomic force microscope (AFM) tip is used to write alkanethiols with 30-nanometer linewidth resolution on a gold thin film in a manner analogous to that of a dip pen. Molecules are delivered from the AFM tip to a solid substrate of interest via capillary transport, making DPN a potentially useful tool for creating and functionalizing nanoscale devices.

https://science.sciencemag.org/content/sci/283/5402/661.full.pdf

"Dip-Pen" Nanolithography

Data from $\mathrm{ab}$-oriented ${\mathrm{YBa}}_{2}{\mathrm{Cu}}_{3}{\mathrm{O}}_{7}/\mathrm{I}/\mathrm{Cu}$ tunnel junctions are presented. Self-assembled monolayers form the insulating tunnel barrier, I. The ${\mathrm{YBa}}_{2}{\mathrm{Cu}}_{3}{\mathrm{O}}_{7}$ features in the tunneling conductance match those of low-leakage $\mathrm{ab}$-oriented ${\mathrm{YBa}}_{2}{\mathrm{Cu}}_{3}{\mathrm{O}}_{7}/\mathrm{Pb}$ junctions. Results show that the zero-bias conductance peak is an Andreev bound state (ABS) of a $d$-wave order parameter. In zero magnetic field, the ABS splits below $\ensuremath{\sim}7\mathrm{K}$, consistent with the presence of a subdominant order parameter at the surface. An applied magnetic field induces further splitting that grows nonlinearly with increasing field.

Observation of surface-induced broken time-reversal symmetry in YBa 2 Cu 3 O 7 tunnel junctions

The First Raman Spectrum of an Organic Monolayer on a High-Temperature Superconductor: Direct Spectroscopic Evidence for a Chemical Interaction between an Amine and YBa2Cu3O7-δ

This paper describes a new method for controlling the deposition of conductive polymer systems onto high-T{sup c} superconductor surfaces. This method relies on the spontaneous adsorption of the pyrrole-terminated alkylamine reagent 1 onto YBa{sup 2}Cu{sup 3}O{sup 7-{delta}} prior to polymerization. Large changes in the polymer growth rates and vast improvements in the polymer morphology are obtained with the use of such adsorbed monolayers. As described, the adsorbed monolayer structures promote radically different polymer deposition properties from those observed previously for the more traditional electrode materials (i.e., Au, Pt, etc.). These unusual observations provided valuable insight into the electrochemical characteristics and local surface electroactivity/conductivity properties of oriented cuprate superconductor films. 16 refs., 2 figs.

Polypyrrole growth on YBa2Cu3O(7-δ) modified wih a self-assembled monolayer of N-(3-aminopropyl)pyrrole: Hardwiring the 'electroactive hot spots' on a superconductor electrode

The surface coordination chemistry of the cuprate superconductor, YBa2Cu3O7-δ has been extensively surveyed using cyclic voltammetry in conjunction with a series of redox-active ferrocenyl containing adsorbate molecules. Evidence supporting the adsorption of molecules with primary alkylamine, secondary alkylamine, tertiary alkylamine, arylamine, thiol, disulfide, and selenol functionalities is reported. Cyclic voltammetry, atomic force microscopy, scanning electron microscopy, X-ray powder diffraction and resistivity vs temperature measurements were utilized to evaluate the influence of the modification conditions on the bulk and surface properties of the high-Tc superconductor. The spontaneous adsorption of redox-active alkylamines, arylamines, and thiols onto the surfaces of cuprate materials has been shown to produce stable and robust monolayer films with no apparent damage to the bulk properties of the underlying superconductors. Of the molecules studied thus far, primary alkylamines have been determi...

Feng Xu

Papers

"Dip-Pen" Nanolithography

Observation of surface-induced broken time-reversal symmetry in YBa 2 Cu 3 O 7 tunnel junctions

The First Raman Spectrum of an Organic Monolayer on a High-Temperature Superconductor: Direct Spectroscopic Evidence for a Chemical Interaction between an Amine and YBa2Cu3O7-δ

Polypyrrole growth on YBa2Cu3O(7-δ) modified wih a self-assembled monolayer of N-(3-aminopropyl)pyrrole: Hardwiring the 'electroactive hot spots' on a superconductor electrode

Surface Coordination Chemistry of YBa2Cu3O7-δ