5 research outputs found
Integrated microfluidic tmRNA purification and real-time NASBA device for molecular diagnostics.
We demonstrate the first integrated microfluidic tmRNA purification and nucleic acid sequence-based amplification (NASBA) device incorporating real-time detection. The real-time amplification and detection step produces pathogen-specific response in < 3 min from the chip-purified RNA from 100 lysed bacteria. On-chip RNA purification uses a new silica bead immobilization method. On-chip amplification uses custom-designed high-selectivity primers and real-time detection uses molecular beacon fluorescent probe technology; both are integrated on-chip with NASBA. Present in all bacteria, tmRNA (10Sa RNA) includes organism-specific identification sequences, exhibits unusually high stability relative to mRNA, and has high copy number per organism; the latter two factors improve the limit of detection, accelerate time-to-positive response, and suit this approach ideally to the detection of small numbers of bacteria. Device efficacy was demonstrated by integrated on-chip purification, amplification, and real-time detection of 100 E. coli bacteria in 100 microL of crude lysate in under 30 min for the entire process
Tunable metallic nanostructures using 3D printed nanosphere templates
The use of two-photon 3D printing to create templates for fabricating reproducible and tunable metallic nanostructures is described. The approach allows the structure of the template to be designed specifically for particular applications, e.g., fluid flow control, surface enhanced Raman spectroscopy, metal enhanced fluorescence etc. Here, we show that this method offers excellent control of the size, pitch and packing of spheres on both conducting and insulating substrates, unlike nanosphere lithography. Gold is deposited through these templates and the template then removed using a plasma etching method. In this way, gold nanotriangles, nanodiamonds and nanocavities have been created and characterized using SEM to determine the accuracy of the structures compared to the software designs. Keywords: 3D printing, Lithography, Metal nanostructures, Electrodepositio
Integrated microfluidic tmrna purification and real-time nasba device for molecular diagnostics
We demonstrate the first integrated microfluidic tmRNA purification and nucleic acid sequence-based amplification (NASBA) device incorporating real-time detection. The real-time amplification and detection step produces pathogen-specific response in &lt; 3 min from the chip-purified RNA from 100 lysed bacteria. On-chip RNA purification uses a new silica bead immobilization method. On-chip amplification uses custom-designed high-selectivity primers and real-time detection uses molecular beacon fluorescent probe technology; both are integrated on-chip with NASBA. Present in all bacteria, tmRNA (10Sa RNA) includes organism-specific identification sequences, exhibits unusually high stability relative to mRNA, and has high copy number per organism; the latter two factors improve the limit of detection, accelerate time-to-positive response, and suit this approach ideally to the detection of small numbers of bacteria. Device efficacy was demonstrated by integrated on-chip purification, amplification, and real-time detection of 100 E. coli bacteria in 100 mu L of crude lysate in under 30 min for the entire process