/npsi/ctrl?action=rtdoc&an=3539033&lang=en http://nparc.cisti-icist.nrc-cnrc.gc.ca/npsi/ctrl?action=rtdoc&an=3539033&lang=frAccess and use of this website and the material on it are subject to the Terms and Conditions set forth at http://nparc.cisti-icist.nrc-cnrc.gc.ca/npsi/jsp/nparc_cp.jsp?lang=en NRC Publications Archive Archives des publications du CNRCThis publication could be one of several versions: author's original, accepted manuscript or the publisher's version. / La version de cette publication peut être l'une des suivantes : la version prépublication de l'auteur, la version acceptée du manuscrit ou la version de l'éditeur. For the publisher's version, please access the DOI link below./ Pour consulter la version de l'éditeur, utilisez le lien DOI ci-dessous.http://dx.doi.org/10.1039/b700322fLab on Chip, 7, 2007-01-01 Microarrays have become one of the most convenient tools for high throughput screening, supporting major advances in genomics and proteomics. Other important applications can be found in medical diagnostics, detection of biothreats, drug discovery, etc. Integration of microarrays with microfluidic devices can be highly advantageous in terms of portability, shorter analysis time and lower consumption of expensive biological analytes. Since fabrication of microfluidic devices using traditional materials such as glass is rather expensive, there is great interest in employing polymeric materials as a low cost alternative that is suitable for mass production. A number of commercially available plastic materials were reviewed for this purpose and poly(methylmethacrylate) Zeonor 1060R and Zeonex E48R were identified as promising candidates, for which methods for surface modification and covalent immobilization of DNA oligonucleotides were developed. In addition, we present proof-of-concept plastic-based microarrays with and without integration with microfluidics.

Ozone treatment is an efficient economical, alternative method for surface activation of poly(dimethylsiloxane) (PDMS). This is illustrated by the derivatization of a PDMS surface with (3-aminopropyl)triethoxysilane (APTES). The apparent surface concentration of amino groups was found to be ca. 10(-8) mol/cm2 using UV/visible spectroscopy of the product from the reaction of the amino groups and fluorescamine. Potential application for micropatterning of biologically active interfaces was demonstrated by the covalent immobilization of oligonucleotides. A simple process for photolithographic patterning on PDMS surfaces has been developed.

The conformational analysis of unsubstituted and alkyl-substituted oligothiophenes and oligo(thienyl)furans by dynamic NMR (DNMR) spectroscopy and ab initio calculations is described. The DNMR studies of oligothiophenes indicate that the conformational exchange is fast even on the 13 C chemical shift scale and that the barriers are too low to be measured by this technique. Ab initio 6-31G** and MP2/6-31G** calculations are in agreement with these experimental findings. Moreover, it is found that the torsional barriers do not change significantly as the chain length is increased. Torsional parameter sets for the MM2 force field are derived for substituted oligothiophenes and oligo(thienyl)furans using the ab initio torsional energy profiles for the appropriate dimers, with the expectation that these parameter sets will be transferable to larger oligomers.

alkanesulfonates) (P3TAS's) containing propanesulfonate, hexanesulfonate, and octanesulfonate substituents have been prepared by oxidative coupling using ferric chloride. The ratio of head-to-tail dyads to head-to-head dyads is 4:1. The extent of jr-conjugation in the polymers, as determined by UV-vis spectroscopy, is relatively independent of whether the polymers are in solution or in the solid state. Polymer films of the sodium salt and sulfonic acid forms are amorphous in contrast to non-sulfonated analogs, i.e., the poly(3-alkylthiophenes), which self-organize into semicrystalline solids. Morphological differences between alkane and alkanesulfonate derivatives of polythiophenes are explained on the basis of ion aggregation which prevents polymer chains from achieving the coplanar conformation required for crystallization. Remarkably, the acid form of the polymers, termed "self-doped", exhibit electronic conductivities in the range 5 x 10~2-10_1 S/cm even though they too are amorphous and devoid of long range order. The photochemistry of P3TAS's, in both their sodium salt and "self-doped" form, was investigated. The primary photochemical process is photosensitization and reaction of singlet oxygen, which leads to photobleaching. In oxygenated solutions, P3TAS's are much more photostable than their non-sulfonated analogs due to quenching of photosensitized singlet oxygen by water. Films of P3TAS's take up atmospheric moisture in ambient air and, as a result, exhibit enhanced photostability compared to their non-sulfonated analogs exposed to ambient conditions. Anhydrous films, however, exhibit rates of photobleaching which are comparable to the poly(3-alkylthiophenes). The acid form of the polymers is found to be more photostable than their corresponding sodium salts. Unlike their non-sulfonated analogs, irradiated films of P3TAS's exposed to ambient atmosphere do not cross-link to form insoluble polymer upon irradiation due to the presence of residual moisture. However, photolithography can be performed on polymer films oxidized with ferric chloride. Anhydrous films of P3TAS's are rendered insoluble upon exposure to UV or visible irradiation, thus affording the deposition of negative polymer images.