4 replies to this topic

[Mind]

News Release Here

BERKELEY, CA — The dream of personalized medicine — in which diagnostics, risk predictions and treatment decisions are based on a patient's genetic profile — may be on the verge of being expanded beyond the wealthiest of nations with state-of-the-art clinics. A team of researchers with the U.S. Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab) has invented a technique in which DNA or RNA assays — the key to genetic profiling and disease detection — can be read and evaluated without the need of elaborate chemical labeling or sophisticated instrumentation. Based on electrostatic repulsion — in which objects with the same electrical charge repel one another — the technique is relatively simple and inexpensive to implement, and can be carried out in a matter of minutes.

"One of the most amazing things about our electrostatic detection method is that it requires nothing more than the naked eye to read out results that currently require chemical labeling and confocal laser scanners," said Jay Groves, a chemist with joint appointments at Berkeley Lab's Physical Biosciences Division and the Chemistry Department of the University of California (UC) at Berkeley, who led this research. "We believe this technique could revolutionize the use of DNA microarrays for both research and diagnostics."

OK, I have read the article a couple of times but I am still not completely sure what type of info they are getting from their technique. Are they actually reading the A-C-T-G of DNA? Or are they just matching known sequences with samples?

[Prometheus]

News Release Here
OK, I have read the article a couple of times but I am still not completely sure what type of info they are getting from their technique. Are they actually reading the A-C-T-G of DNA? Or are they just matching known sequences with samples?

Just like the services provided by 23andme, Navgenics and deCodeMe, this methodology is about matching known sequences with samples but without the time consuming and expensive chemical labeling.

[maestro949]

Are they actually reading the A-C-T-G of DNA? Or are they just matching known sequences with samples?

Yes they are reading the DNA or RNA sequences. Just more efficiently by analyzing the electrical charge of the sample and without having to use fluorescent labeling. Impressive stuff. Once brought to market, this could be very useful for gene expression profiling of supercentenarians and the like.

[treonsverdery]

super awesome

Im thinking that if they use retroreflective microspheres, the kind that cause highway notices to reflect light directly back at you, they could get an order of magnitude higher resolution as their technique goes with: on areas containing single-stranded DNA, also negatively charged but to a lesser degree than double-stranded DNA, the microspheres will levitate above the substrate surface, stacking up in "equilibrium heights" that are dictated by a balance between gravitational and electrostatic forces.

These electrostatic interactions on the microarray surface result in charge-density contrasts that are readily observed. Surface areas containing DNA segments take on a frosted or translucent appearance, and can be correlated to specific hybridizations that reveal the presence of genes, mutations and pathogens.

the microspheres will levitate above the substrate surface, stacking up in "equilibrium heights" that are dictated by a balance between gravitational and electrostatic forces strongly suggests that nterferometry from retroreflective spheres could be ultra height measurment effective; they could even jiggle the array with a sonic tone taking a measurement at each pulse to verify height

thinking about dna computing this detection of matching sequences technique could make a nonaqueous dna computer possible; electrostatics ought to work with a nonpolar fluid like a cfc; the little microspheres would repulse n levitate yet the thing they are responding to could be changed; if the microspheres had a ferromagnetic core they could be lifted up from their places then pulled back giving various computation providing enzymes that do [and, or, not] an opportunity to modify the dna at the array element

wikipedia about a dna computer says
The arrangement of this device looks like that of a tic-tac-toe grid and consists of nine wells coated with culture cells. The cell-containing wells are filled with a solution that contain DNA strands coding for red or green fluorescent dyes.

electrolytic capacitors are what makes me think electrostatics could work at a fluid nonpolar place; air gap capacitors also work thus its just a matter of the length between items

Edited by treonsverdery, 03 July 2008 - 03:33 AM.

[Mind]

The "Lab on a Chip" keeps getting closer and closer.

Currently, test tube-size fluid samples are sent to external labs for analysis, usually requiring a 24- to 48-hour wait for a result.

"Time is of the essence when dealing with an infectious disease such as meningitis," Landers said. "We can greatly reduce that test time, and reduce the anxiety a patient experiences while waiting."

Landers said the research also dovetails with the trend toward "personalized medicine," in which medical care increasingly is tailored to the specific genetic profile of a patient. Such highly specialized personalized care can allow physicians to develop specific therapies for patients who might be susceptible to, for example, particular types of cancers.

Simplifying genetic testing, and reducing the costs of such tests, could help pave the way toward routine delivery of such personalized care based on an individual's genetic profile.

Hand-held micro labs also would be useful to crime scene investigators who could collect and analyze even a tiny sample of blood or semen on-site, enter the finding into a genetic database, and possibly identify the perpetrator very shortly after a crime has occurred.