Thinking beyond Jay-Z and Coldplay, researchers at Ohio State University have turned a standard compact disk into a biochemical laboratory. Their specially designed CD completely automates a commonly used assay for classifying HIV and some cancers, eliminating many tedious steps and producing results in one-tenth of the time.
As early as four decades ago, researchers at Monsanto tried to use centrifugal force to push liquids through a series of chambers on a plastic disk, says L. James Lee of Ohio State. His updated “lab on a CD” contains a series of wells and channels, each no deeper than the width of a human hair. Blood or cell samples are placed in one set of the disk’s chambers. Test chemicals are then mixed sequentially by changing the speed that the CD rotates: Solutions in wells closer to the outside move outward at lower rotation speeds, while those closer to the center remain in place until the CD spins more quickly.
Besides saving time, the lab CD also uses less of the expensive antibodies needed for common disease tests, cutting material costs by up to 90 percent. Within two years, technicians may be listening to their favorite music CDs while their experiments spin nearby on a similar disk.