Electricity and refrigeration not essential for DNA purification

Extracting DNA has never been so easy as it is with the new SNAP (System for Nucleic Acid Preparation), designed by Boston University professor Catherine Klapperich. This small device, built on simple technique, using cheap inputs can help in purifying DNA from all kinds of body fluids, including blood. One just needs to run the blood through polymer-lined straw where in the DNA is trapped which then can be mailed to the lab for further anlysis.

This new device has lot of potential in poor countries and other rural communities that would not only save money, but time too. Usually, the samples sent to the labs for DNA are very sensitive if not stored at freezing temperatures. In mnay cases, the DNA gets degraded by the time they reach labs for extraction. In this case, this device helps that degradation problems as they will be more stable once extracted and then sent to the labs.

The DNA is more stable once extracted than in the sample. This is due to many chemicals in the sample that degrade the quality and quantity of DNA. In reality, DNA is more stable than does the RNA. So, this device could save us from lots of hurdles in testing people for diseases such as AIDS and other easily transmitted diseases. To understand how the DNA is extracted from blood, read this small description here, provided by Technology Review at MIT. The conventional method of extracting DNA from blood involves a number of instruments: researchers first break open blood cell walls, either with chemicals or by shaking the blood, in order to get at genetic material inside cells. They then add a detergent to wash away the fatty cell walls, and spin the DNA out of solution with a centrifuge. The SNAP prototype performs a similar series of events with a bicycle pump, some simple chemicals, and a specialized straw lined with a polymer designed to attract and bind DNA. A clinician first takes a fluid sample, such as blood or saliva from a patient, and injects it into the disposable straw within the device. A large cap on the device contains two small packets: a lysis buffer and an ethanol wash. Pressure from the pump releases the lysis buffer, which breaks open cells in the fluid, releasing DNA. A second pump of air releases ethanol, which washes out everything but the DNA.

At this point, this device is used to test only some fluids such as nasal. Once its tested for other fluids, it will have more applicability. One problem with this at this stage is that the total DNA obtained is less in quantity, but exceptionally good in quality. And small quantities were never a problem after the innovative polymerase chain reaction, invented by kary Mullis.

For now, lets hope that this new device will take the world by storm. Kudos to Dr. Klapperich and his students at Boston University.

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