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Device Can Extract DNA With Full Genetic Data In Minutes
vinces99 writes "Imagine taking a swab of saliva from your mouth and, within minutes, having your DNA ready for genome sequencing. A new device from University of Washington engineers and a company called NanoFacture can extract human DNA from fluid samples in a simpler, more efficient and environmentally friendly way than conventional methods. It will give hospitals and labs a much easier way to separate DNA from human fluid samples, which will help with genome sequencing, disease diagnosis and forensic investigations."
GATTACA here we come!
Obama's legacy: (N)othing (S)ecure (A)nywhere and (T)error (S)imulation (A)dministration
Guy comes into an ER unconscious...
Darn. I was waiting for a good joke.
They can take my LifeAlert pendant when they pry it from my cold dead fingers.
W engineers designed microscopic probes that dip into a fluid sample – saliva, sputum or blood – and apply an electric field within the liquid. That draws particles to concentrate around the surface of the tiny probe. Larger particles hit the tip and swerve away, but DNA-sized molecules stick to the probe and are trapped on the surface.
I read through the entire article link, and didn't learn a whole lot about how it actually performs. The above paragraph was the only technical information included. From what I can see, neither really tests performance against really challenging samples with a lot of crud or difficult-to-extract material. We only have the PR blurb's claim that it's better than a typical Miniprep column.
Found a couple of papers that might be more relevant:
Size-Specific Concentration of DNA to a Nanostructured Tip Using Dielectrophoresis and Capillary Action (Has downloadable PDF)
Nanotips for single-step preparation of DNA for qPCR analysis (Paywall)
Ok, from the first paper, we find out what this is really for:
Extracellular DNA is of great interest in the fields of disease diagnostics and environmental molecular biology. Unlike the genomic DNA in normal cells, extracellular DNA is the free DNA released from dead cells. Thus, extracellular DNA circulating in body fluids can be used as an early indicator for various acute diseases such as cancer. For example, the concentration of extracellular DNA for a normal person is 30ng/mL, but the concentration is increased to 300 ng/mL for a cancer patient. When the issue comes to environmental monitoring, extracellular DNA dissolved in lakes and soil is an indicator for environmental quality because the dissolved DNA is generated from cell lysis and excretion. In spite of such a great potential, the study of extracellular DNA is limited by the standard sample preparation methods.
The conventional methods begin with filtering, centrifuging, and collecting DNA from a raw sample. In aggressive experimental protocols, genomic DNA from normal cells is released and mixed with extracellular DNA. In addition, a few hours is required for the sample preparation process, which can degrade and mutate extracellular DNA.6 As a result, the original information of extracellular DNA is partially or completely lost. Therefore, a rapid process that can concentrate extracellular DNA is very important for identifying pathogenic information. This paper presents a size-specific concentration mechanism directly extracting extracellular DNA from a sample mixture using a nanostructured tip. The concentration process is performed with two sequences: (1) an alternating current (AC) electric field is applied to attract DNA and other bioparticles in the vicinity of a nanotip; (2) only the DNA is size-selectively captured onto the nanotip by the combination of dielectrophoresis and capillary action. In the analytical section, the forces involved in the concentration are estimated to investigate the capturing process. An analytical model is presented for capillary induced size-selectivity that is described as the function of the ratio of a particle to a tip diameter.
Basically, this is a special purpose method for concentrating extra-cellular DNA while leaving whole cell material intact. It's not meant to compete against a Miniprep, but analyze a whole different type of sample material; you are trying to fish out what genetic material is already floating around outside of your cells. Really a niche kind of research thing, I don't know if this will make a whole lot of impact, either practically, academically, or economically.
Guy comes into an ER unconscious. When he finally wakes up they ask him what happened.
"I was having a quiet round of golf with my wife," he tells the doctor, "when she sliced her ball into a pasture of cows. We went to look for it, and I noticed one of the cows had something white in its rear end. I walked over and lifted up the tail, and sure enough, there was my wife's golf ball stuck right in the cow's butt. That's when I made my mistake."
"What did you do?" asks the doctor.
"Well, as I was standing there holding up the tail, I yelled to my wife, 'Hey, this looks like yours!'"
They can take my LifeAlert pendant when they pry it from my cold dead fingers.