Last year, we reported on some research that was repurposing personal glucose meters (PGMs; the little devices that detect your blood sugar level) to enable the detection of a variety of other analytes (cocaine and uranium, among other things). Now the same team have adapted the idea to the detection of DNA, with impressive precision and sensitivity.

But before you rush out and set up a street-corner screening service, there’s a little more chemistry involved. The glucose meters are just plain old glucose meters and don’t actually detect DNA; the trick lies in converting the chemical you’re interested in to a glucose response that the PGM can detect.

Effectively, the team have built a sort of chemical transducer that takes a DNA signal and turns it into a glucose signal. The transducer has two parts: an enzyme – DNA invertase – that turns sucrose into glucose, and a magnetic bead. The enzyme and the bead are each connected to DNA strands that match up to the target DNA strand you hope to detect. So, in the presence of the target DNA, the magnetic bead and the enzyme are brought together and you can then remove the whole thing with a magnet, pop it in some sucrose, and in seconds your glucose meter can tell you if you’ve got hepatitis B (or something else, probably, but that’s what these chaps were looking for).

So, in future you might find yourself asking to borrow a diabetic friend’s PGM. ‘I didn’t know you had diabetes,’ they’ll remark, and you can smugly reply, ‘ I don’t – I’ve got hep B’.

Philip Robinson

                  

Source:
http://prospect.rsc.org/blogs/cw/?feed=rss2