Here is an interesting nanotechnology being developed at the Sandia National Laboratories:
A five-pound, hand-held medical diagnostic device being developed at the National Nuclear Security Administration’s Sandia National Laboratories promises to be this ticket to better health for millions of Americans.
“We have taken technology that we’ve worked on for several years — Sandia’s lab-on-a-chip devices — and are adapting them for use in medical diagnostics,” says Anup Singh, project lead. “We’ve tested saliva samples from healthy patients for gum disease, and within the next few months we will begin using the diagnostic tool to test diseased samples.”
As part of the immunoassay process, antibodies specific for biomarkers of interest, such as gum or heart disease, are tagged with a fluorescent dye and then mixed with a patient’s saliva or blood. Biomarkers present in the sample attach themselves to the fluorescent antibody. The mixture is injected into a microchip using a syringe. An applied electric field forces the sample to flow through a microchannel that is two to five centimeters long, tens of microns deep, and a few hundred microns wide.
As the sample moves through the channel, cast-in-place porous polymers in the microchannel sort molecules based on their sizes and electrical charges. If biomarkers for the disease are present in the patient’s sample, the lab-on-a-chip analysis will separate fluorescent antibodies bound to the biomarker from unbound antibodies.
A photomultiplier tube then detects the fluorescence emission with extreme sensitivity. After quantifying the relative fluorescence of the two species — bound and unbound antibodies — researchers can determine the amount of biomarker present in the patient’s sample. If the sample contains significant fluorescence emission from a bound antibody, indicating that biomarkers are present above a certain level, a doctor could conclude that the patient has or will eventually get the disease for which he or she is being tested. At the conclusion of the test, while the patient is still in the doctor’s office, preventive or therapeutic care could begin.