This past week, two articles in the Wall Street Journal by John Carreyou (October 15 and 16) described the apparent failure of the much hyped Theranos Edison analyzer. However, Theranos’ woes does not mean that laboratory test innovation is stagnant. Below are three promising examples of miniaturized laboratory test devices which are not veiled in secrecy.
In this week’s NIH Director’s Blog, Francis Collins described a point of care test for detection of circulating Ebola virus. This device consists of a microfluidic chip for sample preparation connected to an optofluidic chip for virus detection. A drop of extracted nucleic acid is pipetted into the microfluidic chip, where it undergoes the necessary preparatory steps to expose RNA. If Ebola virus RNA is present it binds to complementary synthetic sequences attached to magnetic microbeads in the chip. A small magnet collects the microbeads, while extraneous material is washed away. Ebola RNA attached to microbeads is labeled with fluorescent probes, which are detected in the optofluidic chip. Specificity is good enough to distinguish Ebola virus from closely related Marburg and Sudan viruses. This hybrid device has not yet been field tested. References and a photo of the connected chips can be seen at:
http://directorsblog.nih.gov/2015/10/22/shining-light-on-ebola-virus-for-faster-diagnosis/
A couple of other lab on a chip devices were presented at this summer’s 2015 AACC Annual Meeting and Clinical Lab Expo. Researchers from DiaSys Diagnostics India presented a point of care device, named QDx Insta Lab, which can perform multiple laboratory tests on a few drops of blood obtained from a finger stick. The device consists of a microfluidic cartridge and electrochemical biosensors. The company presented data that compared patient test results from QDx with conventional laboratory instruments. Correlation coefficient was 0.95. Precision for all tests was 3% or less.
http://www.diasys.in/lab-diagnostics/
NOWDiagnostics Inc. (Springdale, AR) has developed the ADEXUSDx brand, which was registered with the FDA in December 2014. The product line consists of more than 50 tests, which can be performed on a drop of blood. Results are read on the NOWDiagnostics Lateral Flow Reader. An hCG whole blood pregnancy test has received 510(k) clearance by the FDA for distribution in the U.S. Six tests are available for sale in Europe including hCG, troponin, myoglobin, acetaminophen, salicylate and methanol. Numerous other tests for sexually transmitted disease, infectious disease, and food tolerance are under development.