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Intelligent front-end sample preparation tool using acoustic streaming

Vreeland, Erika C.; Smith, Gennifer T.; Edwards, Thayne L.; James, Conrad D.; McClain, Jaime L.; Murton, Jaclyn K.; Kotulski, J.D.; Clem, Paul G.

We have successfully developed a nucleic acid extraction system based on a microacoustic lysis array coupled to an integrated nucleic acid extraction system all on a single cartridge. The microacoustic lysing array is based on 36{sup o} Y cut lithium niobate, which couples bulk acoustic waves (BAW) into the microchannels. The microchannels were fabricated using Mylar laminates and fused silica to form acoustic-fluidic interface cartridges. The transducer array consists of four active elements directed for cell lysis and one optional BAW element for mixing on the cartridge. The lysis system was modeled using one dimensional (1D) transmission line and two dimensional (2D) FEM models. For input powers required to lyse cells, the flow rate dictated the temperature change across the lysing region. From the computational models, a flow rate of 10 {micro}L/min produced a temperature rise of 23.2 C and only 6.7 C when flowing at 60 {micro}L/min. The measured temperature changes were 5 C less than the model. The computational models also permitted optimization of the acoustic coupling to the microchannel region and revealed the potential impact of thermal effects if not controlled. Using E. coli, we achieved a lysing efficacy of 49.9 {+-} 29.92 % based on a cell viability assay with a 757.2 % increase in ATP release within 20 seconds of acoustic exposure. A bench-top lysing system required 15-20 minutes operating up to 58 Watts to achieve the same level of cell lysis. We demonstrate that active mixing on the cartridge was critical to maximize binding and release of nucleic acid to the magnetic beads. Using a sol-gel silica bead matrix filled microchannel the extraction efficacy was 40%. The cartridge based magnetic bead system had an extraction efficiency of 19.2%. For an electric field based method that used Nafion films, a nucleic acid extraction efficiency of 66.3 % was achieved at 6 volts DC. For the flow rates we tested (10-50 {micro}L/min), the nucleic acid extraction time was 5-10 minutes for a volume of 50 {micro}L. Moreover, a unique feature of this technology is the ability to replace the cartridges for subsequent nucleic acid extractions.

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TYPE SAND Report YEAR 2009
OSTIDOI

Fabrication of (Ba,Sr)TiO3 high-value integrated capacitors by chemical solution deposition

IEEE International Symposium on Applications of Ferroelectrics

Sigman, Jennifer; Clem, Paul G.; Brennecka, Geoffrey L.; Tuttle, Bruce T.

This report focuses on our recent advances in the fabrication and processing of barium strontium titanate (BST) thin films by chemical solution depositiion for next generation fuctional integrated capacitors. Projected trends for capacitors include increasing capacitance density, decreasing operating voltages, decreasing dielectric thickness and decreased process cost. Key to all these trends is the strong correlation of film phase evolution and resulting microstructure, it becomes possible to tailor the microstructure for specific applications. This interplay will be discussed in relation to the resulting temperature dependent dielectric response of the BST films.

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TYPE Conference YEAR 2008
ScopusOSTI

Advances in (Ba,Sr)TiO3 high value capacitors fabricated by chemical solution deposition

Clem, Paul G.; Brennecka, Geoffrey L.; Tuttle, Bruce T.

This report focuses on our recent advances in the fabrication and processing of barium strontium titanate (BST) thin films by chemical solution deposition for next generation functional integrated capacitors. Projected trends for capacitors include increasing capacitance density, decreasing operating voltages, decreasing dielectric thickness and decreased process cost. Key to all these trends is the strong correlation of film phase evolution and resulting microstructure, it becomes possible to tailor the microstructure for specific applications. This interplay will be discussed in relation to the resulting temperature dependent dielectric response of the BST films.

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TYPE Conference YEAR 2008
OSTI

Microfluidics and microacoustics for miniature flow cytometry

2007 NSTI Nanotechnology Conference and Trade Show - NSTI Nanotech 2007, Technical Proceedings

Ravula, Surendra K.; Branch, Darren W.; Sigman, Jennifer; Clem, Paul G.; Kaduchak, Gregory; Brener, Igal B.

Flow cytometry is an indispensable tool in clinical diagnostics, for example in cancer, AIDS, infectious disease outbreaks, microbiology, and others. The cost and size of existing cytometers precludes their entry into field clinics, water monitoring, agriculture/veterinary diagnostics, and rapidly deployable biothreat detection. Much of the cost and footprint of conventional cytometers is dictated by the high speed achieved by cells or beads in a hydrodynamically focused stream. This constraint is removed by using ultrasonic focusing in a parallel microfluidic architecture. In this paper, we describe our progress towards a microfabricated flow cytometer that uses bulk and microfabricated planar piezoelectric transducers in glass microfluidic channels. In addition to experimental data, initial modeling data to predict the performance of our transducers are discussed.

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TYPE Conference YEAR 2007
ScopusOSTI
Results 126–150 of 179
Results 126–150 of 179