Researchers from the University of Michigan and University of Indiana developed a new protein biomarker test platform that is believed to improve diagnostic testing through its accurate and simultaneous measurement of multiple proteins.
In just two hours, the new system can detect the presence of a disease without any washing steps while using only a very small volume of blood plasma. The protein test was developed in Shuichi Takayama's Micro/Nano/Molecular Biotechnology Lab, which is affiliated with the University of Michigan's Department of Biomedical Engineering and the Macromolecular Science and Engineering Program. Its micropatterning method gives the platform the ability to complete all of these tasks effectively.
The researchers tested the efficacy of the procedure in measuring protein biomarkers from cytokine-stimulated cells and also the plasma of bone marrow transplant patients. They mixed a few microliters of the blood plasma with poly(ethylene glycol) which was then added to a microwell in a custom 384-well microplate. The researchers then dispensed microdroplets of dextran containing pairs of antibody beads into microbasins within the sample well. After two hours, plasma protein biomarkers diffused from the poly(ethylene glycol) phase to the dextran droplets and were sandwiched by the antibody beads.
"Just as oil and water remain immiscible, we use two aqueous solutions that do not mix with each other," said Dr. Takayama, Professor of Biomedical Engineering and Macromolecular Science and Engineering in this World Scientific media release. "Interestingly, these solutions can be patterned into arrays, whereas standard no-wash protein test reagents normally just mix together in solution. This novel capability makes it possible, for the first time, to measure multiple diagnostic proteins at a time in a no-wash format test."
The multiphase polymer systems allow for amplified and luminescent signals for the plasma protein biomarkers. As a result, the signal intensity from the antibody beads is proportional to the levels of disease biomarkers in the blood plasma, and if protein levels exceed the clinical threshold, then the patient is determined to possess whatever disease they are being tested for. Current diagnostic blood testing can be inaccurate, as the results can be misinterpreted due to variations in your body and what you eat, while noncancerous conditions can cause abnormal tests results. Cancer can also be present if a test says it's not.
The researchers hope that their new system can both expedite the diagnosis process while providing more accurate results through the efficient testing process. You can read more about the research in the journal TECHNOLOGY.
