Selective Attachment (selective + attachment)

Distribution by Scientific Domains

Selected Abstracts

D -Glucose as a Pentavalent Chiral Scaffold

Till Opatz
Abstract A novel carbohydrate-based scaffold for combinatorial chemistry has been developed. This scaffold allows the selective attachment of five different side chains, giving rise to products of enormous structural diversity. As a demonstration of its usefulness, a series of model compounds has been prepared in high purity and yield by multistep parallel synthesis on a solid phase. ( Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003) [source]

Nanolithography: Thermochemical Nanolithography of Multifunctional Nanotemplates for Assembling Nano-Objects (Adv. Funct.

On page 3696, Wang et al. report on the nanoscale chemical surface patterning of different chemical species (amine, thiol, aldehyde, and biotin) in independent nanopatterns by the iterative application of thermochemical nanolithography. Due to the unique chemical stability of the patterns, the resultant substrates can be stored for weeks and subsequently be used for the selective attachment of nanometer-sized objects, such as proteins or DNA, using standard chemical protocols. [source]

Localized Attachment of Carbon Nanotubes in Microelectronic Structures

Xavier Joyeux
Carbon Nanotubes (CNTs) are covalently modified by the monodiadozium salt of ethylene dianiline; further diazotation of the free amino group permits the selective attachment of these CNTs to the Si or Ti bottom of SiO2 trenches. The symmetrical electrografting of the bottom of the trenches, followed by the attachment of pristine CNTs, is also described. [source]

Direct Microfabrication of Topographical and Chemical Cues for the Guided Growth of Neural Cell Networks on Polyamidoamine Hydrogels

Gabriel Dos Reis
Abstract Cell patterning is an important tool for organizing cells in surfaces and to reproduce in a simple way the tissue hierarchy and complexity of pluri-cellular life. The control of cell growth, proliferation and differentiation on solid surfaces is consequently important for prosthetics, biosensors, cell-based arrays, stem cell therapy and cell-based drug discovery concepts. We present a new electron beam lithography method for the direct and simultaneous fabrication of sub-micron topographical and chemical patterns, on a biocompatible and biodegradable PAA hydrogel. The localized e-beam modification of a hydrogel surface makes the pattern able to adsorb proteins in contrast with the anti-fouling surface. By also exploiting the selective attachment, growth and differentiation of PC12 cells, we fabricated a neural network of single cells connected by neuritis extending along microchannels. E-beam microlithography on PAA hydrogels opens up the opportunity of producing multifunctional microdevices incorporating complex topographies, allowing precise control of the growth and organization of individual cells. [source]

Photolithographic Patterning of C2C12 Myotubes using Vitronectin as Growth Substrate in Serum-Free Medium

Peter Molnar
The C2C12 cell line is frequently used as a model of skeletal muscle differentiation. In our serum-free defined culture system, differentiation of C2C12 cells into myotubes required surface-bound signals such as substrate-adsorbed vitronectin or laminin. On the basis of this substrate requirement of myotube formation, we developed a photolithography-based method to pattern C2C12 myotubes, where myotubes formed exclusively on vitronectin surface patterns. We have determined that the optimal line width to form single myotubes is approximately 30 ,m. To illustrate a possible application of this method, we patterned myotubes on the top of commercial substrate-embedded microelectrodes. In contrast to previous experiments where cell patterning was achieved by selective attachment of the cells to patterned surfaces in a medium that contained all of the factors necessary for differentiation, this study illustrates that surface patterning of a signaling molecule, which is essential for skeletal muscle differentiation in a defined system, can result in the formation of aligned myotubes on the patterns. This technique is being developed for applications in cell biology, tissue engineering, and robotics. [source]