When Smaller Is Better for Biological Scanning

A few hun­dred dol­lars and 24 hours: That’s what’s required to scan bio­log­ical mate­rials for impor­tant bio­markers that signal dis­eases such as dia­betes or cancer, using industry stan­dard equip­ment. But sup­pose you wanted to mon­itor live cancer cells. For that you’d have to use an entirely dif­ferent method. It takes just as long but requires a whole other set of expen­sive top-​​end instru­men­ta­tion. Want to look at bac­teria instead? Be pre­pared to wait a few days for it to grow before you can get a mean­ingful result.

Researchers face enor­mous time con­straints and finan­cial hur­dles from having to run these analyses on a reg­ular basis. To solve this problem, Tania Konry, an assis­tant pro­fessor of phar­ma­ceu­tical sci­ences at North­eastern Uni­ver­sity, has devel­oped a single instru­ment that can do all of the scans men­tioned above at a frac­tion of the time and cost. That’s because it uses con­sid­er­ably less mate­rial and ultra-​​sensitive detec­tion methods to do the same thing.

Konry’s cre­ation, Scan­Drop, is a portable instru­ment no bigger than a shoebox that has the capacity to detect a variety of bio­log­ical spec­imen. For that reason it will ben­efit a wide range of users beyond the med­ical com­mu­nity, including envi­ron­mental mon­i­toring and basic sci­en­tific research.

The instru­ment acts as a minia­ture sci­ence lab, of sorts. It con­tains a tiny chip, made of polymer or glass, that is con­nected to equally tiny tubes. An extremely small-​​volume liquid sample—whether it’s water or a bio­log­ical fluid such as serum—flows in one of those tubes, through the lab-​​on-​​a-​​chip device, and out the other side. While inside, the sample is exposed to a slug of micro­scopic beads func­tion­al­ized to react with the lab test’s search para­me­ters. For example, one type of bead could be cov­ered with anti­bodies that selec­tively bind to e. coli to test water quality. Other types could detect cancer bio­markers or bind to the tetanus virus to test for immunity.

“It can be any bio­log­ical agent,” Konry said. “We take the same approach.”

The beads flu­o­resce when the spe­cific marker or cell in ques­tion has been detected; from there, an analysis by Scan­Drop can pro­vide the con­cen­tra­tion levels of that marker or cell.

Because the vol­umes being tested with Scan­Drop are so small, the testing time dwin­dles to just min­utes. This means you could get near-​​real time mea­sures of a changing sample—be it bac­teria levels in a flowing body of water or dynamic insulin levels in the blood­stream of a person with diabetes.

Konry noted that not only are other testing mech­a­nisms pro­hib­i­tively expen­sive, but they are also fairly use­less in the field—particularly in remote areas—because the instru­ments are large and require long times for analysis. By com­par­ison, ScanDrop’s porta­bility makes it much more func­tional and effi­cient in the field.

Her team recently joined forces with a group at the Lawrence Berkeley National Lab, which devel­oped soft­ware that can remotely con­trol ScanDrop’s activity from any­where on the planet. This func­tion­ality could be par­tic­u­larly useful when the instru­ment is set up in the field to con­tin­u­ously mon­itor the envi­ron­ment. The achieve­ment, Konry said, adds yet another level of effi­ciency to the system. The research was recently reported in the journal PLOS One.