Chip and Dip DNA Testing: It’s Fast!

It’s frustrating to spend hours, maybe days, working a criminal case only to see your suspect walk out of jail moments after booking is complete. A quick phone call to a bondsman and off they go. Now, if officers had rock-solid evidence, such as DNA, judges wouldn’t be so quick to release offenders back to the streets where they may commit another crime before their court date.

Thanks to Andrew Hopwood at the Forensic Science Service and Frederic Zenhausern from the Center for Applied NanoBioscience and Medicine in Arizona, the days of pre-trial revolving door justice may soon be a thing of the past.

These two scientists have developed an impressive device that allows technicians to simply obtain a cheek swab (DNA sample), test it, and presto…four hour DNA results!

The test is actually fairly simple. As stated, technicians swab the inside of the suspect’s cheek, mix the sample with a solution, and and then place it on a special platform (a chip) inside the machine. The platform (microfluidic platform) extracts the DNA, amplifies it (makes exact copies), and then, through laser electrophoresis (remember, the old method used gels and later a genetic analyzer—still electrophoresis, only slower) the DNA can be compared to a victim, suspect, or other evidence.

And all this is completed in just four short hours! Older methods of DNA testing sometimes required a period of approximately 24 hours simply to extract DNA from the evidence. This method required the sample to soak in an enzyme at least overnight before scientists could begin the actual testing.

Hopwood and Zenhausern are now hoping to reduce turnaround time of their already lightening-fast chip (the platform) and dip (the swabbing) system to a mere two hours!

If only they could do something about the laboratory backlogs…