A potential handheld device powered by a nanochip-based sensor that detects an oral cancer marker in human saliva. Credit: Daphika S. Dkhar
Bioengineers have designed a sensor that can detect minute traces of cyfra-21-1, a protein marker found in the saliva of oral cancer patients1.
The sensor could potentially be used to develop a disposable nanochip for rapid cancer diagnosis, says a team at the Indian Institute of Technology (BHU) Varanasi.
Existing cancer-detecting sensors are complex and time-consuming to make and cannot be used as bedside diagnostic kits. To devise a portable one, the scientists deposited gold and gadolinium hexacyanoferrate nanoparticles and graphene oxide on a screen-printed electrode.
The team, led by Pranjal Chandra, then attached antibodies of the marker to the sensor and exposed it to solutions containing clinically relevant concentrations of the marker (2 to 50 ng/ml). As concentrations of the marker increased, and it latched onto the antibodies, the sensor’s current response decreased.
The sensor detected cyfra-21-1 selectively even in the presence of interfering agents including cysteine, alanine, glycine, serum albumin, glucose, urea, glutamic acid, uric acid, ascorbic acid and citric acid, which are found in human saliva. It detected the marker within a few minutes and retained its efficiency after being stored in a refrigerator for 10 weeks.
Unlike traditional sensors, this one doesn’t require any external charge carriers. It could be converted into a simple, handheld point-of-care device for oral cancer diagnosis, says Chandra.
