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The crystallization behavior of amorphous TiOxNy (x>>y) thin films was investigated by in-situ transmission electron microscopy. The Johnson-Mehl-Avrami-Kozolog (JMAK) theory is used to determine the Avrami exponent, activation energy, and the phase velocity pre-exponent. Addition of nitrogen inhibits diffusion, increasing the nucleation temperature, while decreasing the growth activation energy. Kinetic variables extracted from individual crystallites are compared to JMAK analysis of the fraction transformed and a change of 6 percent in the activation energy gives agreement between the methods. From diffraction patterns and index of refraction the crystallized phase was found to be predominantly anatase.

We present a rapid method for the identification of viruses using microfluidic chip gel electrophoresis (CGE) of high-copy number proteins to generate unique protein profiles. Viral proteins are solubilized by heating at 95[degrees]C in borate buffer containing detergent (5 min), then labeled with fluorescamine dye (10 s), and analyzed using the [micro]ChemLab CGE system (5 min). Analyses of closely related T2 and T4 bacteriophage demonstrate sufficient assay sensitivity and peak resolution to distinguish the two phage. CGE analyses of four additional viruses--MS2 bacteriophage, Epstein-Barr, respiratory syncytial, and vaccinia viruses--demonstrate reproducible and visually distinct protein profiles. To evaluate the suitability of the method for unique identification of viruses, we employed a Bayesian classification approach. Using a subset of 126 replicate electropherograms of the six viruses and phage for training purposes, successful classification with non-training data was 66/69 or 95% with no false positives. The classification method is based on a single attribute (elution time), although other attributes such as peak width, peak amplitude, or peak shape could be incorporated and may improve performance further. The encouraging results suggest a rapid and simple way to identify viruses without requiring specialty reagents such as PCR probes and antibodies.

Efficient and rapid isolation of mRNA is important in the field of genomics as well as in the clinical and pharmaceutical arena. We have developed UV-initiated methacrylate-based porous polymer monoliths (PPM) for microfluidic trapping and concentration of eukaryotic mRNA. PPM are cast-to-shape and are tunable for functionalization using a variety of amine-terminated molecules. Efficient isolation of eukaryotic mRNA from total RNA was first mathematically modeled and then achieved using PPM in capillaries. Purification protocols using oligo dT's, locked nucleic acid substituted dT's, and tetramethylammonium chloride salts were characterized, mRNA yield and purity were compared with mRNA isolated by commercial kits with statistically equivalent yields and purifies (determined by qPCR ratio of 18s rRNA and Gusb mRNA markers). Even after extracting 16 [micro]g of mRNA from 315 [micro]g of total RNA, the 0.4-[micro]L volume monolith showed no signs of saturation. Elution volumes were below 20 [micro]L with concentrations up to 1 [micro]g/[micro]L. In addition, the polymeric material exhibited exceptional stability in a range of conditions (pH, temperature, dryness) and was stable for a period of months. All of these characteristics make porous polymer monoliths good candidates for potential microfluidic sample preconcentrators and puritiers.