Electrical Engineering and Medicine, Hand-in-Hand
A group of researchers at the University of Virginia have developed a Lab on a Chip (LOC) device capable of detecting cancer much more quickly than traditional lab analyses.
Lead researcher Ali Rohani holding the LOC device. Image courtesy of the University of Virginia.
The team is led by graduate electrical engineering student Ali Rohani and supervised by associate electrical and computer engineering professor Nathan S. Swami (PDF). They’ve been working in conjunction with researchers from UVA’s School of Medicine and School of Engineering and Applied Science (SEAS).
Applied Lab on a Chip Technology
Lab on a Chip (LOC) tech is a subset of MEMS (microelectromechanical systems) that deals in the miniaturization of analyses that traditionally occur in a laboratory setting.
LOC often deals with microfluidics, the handling of extremely small volumes of liquids on a nanoscale. In a medical context, this often means being able to test body fluids like blood in very small amounts.
LOC technology has been studied in the context of medicine since the 1990s. It’s capable of being used to detect and monitor HIV, diabetes, and multiple other diseases. It’s also been used to detect cancer through the identification of biomarkers called exosomes.
Finding a Needle in a Haystack
Finding evidence of early-stage cancer is difficult. Rohani likens the process to “finding Waldo” of “Where’s Waldo?” fame.
Like many other LOC-based technologies, Rohani’s approach aims to identify cancer based on a set of characteristics found in the blood— like how Waldo’s identified by his distinctive hat, shirt, and glasses. However, this project focuses on the use of electrical signals.
Prostate cancer proteins, like any protein, have their own distinct chemical and electrical profile. Rohani’s tech takes advantage of this built-in set of identifiers.
The chip begins with a blood sample in a high-salt serum.
A representation of a serum on the LOC with a uniform concentration of salt. Image courtesy of the University of Virginia.
Next, electrical signals are applied to this environment at a specific frequency which stimulates the prostate cancer proteins. These signals keep the undesired proteins in the high-salt serum and create what Rohani calls a "black hole" of salt concentration where the prostate cancer proteins then gather.
The sensor placed inside this "black hole" is then able to measure for only the desired prostate cancer proteins.
A representation of the LOC's sensor measuring a cluster of proteins in the low-salt region of the chip. Image courtesy of the University of Virginia.
Without interfering proteins in the way, the sensor can determine the presence of prostate cancer proteins with extraordinary accuracy and with a very small sample of blood.
Current Prostate Cancer Detection
Current blood-based early prostate cancer detection is imperfect and requires blood samples to be sent to a lab for analysis.
A prostate-specific antigen (PSA) blood test is designed to detect levels of a PSA, which is created in the prostate gland. Statistically, higher amounts of PSA in the blood correlates to higher instances of prostate cancer.
However, around 15% of men who have “normal” levels of PSA in their blood will be confirmed to have prostate cancer upon biopsy. Also, many factors may affect the levels of PSA in the blood aside from cancer.
Results from a PSA blood test typically take one to two weeks to be relayed to patients.
Rohani hopes to make it possible to detect early-stage cancer within 10 minutes and with only a small sample of blood. Beyond that, he hopes that his project will avoid both the false positives and false negatives that are common with most cancer detection.
This technology could make early prostate cancer detection more reliable and accessible.