Novel technique to detect biomarker for cancer
Researchers are working to develop a new screening technique that's more than 300 times as effective at detecting a biomarker for diseases like cancer than current methods. The technique, published in the Journal of the American Chemical Society, uses nanoparticles with nickel-rich cores and platinum-rich shells to increase the sensitivity of an enzyme-linked immunosorbent assay (ELISA).
ELISA is a test that measures samples for biochemicals, such as antibodies and proteins, which can indicate the presence of cancer, HIV, pregnancy and more.
When a biochemical is detected, the test generates a colour output that can be used to quantify its concentration. The stronger the colour is, the stronger the concentration. The tests must be sensitive to prevent false negatives that could delay treatment or interventions, the researchers said.
"This work sets the record for the catalytic efficiency of peroxidase mimic," said researcher Xiaohu Xia, Assistant Professor at the University of Central Florida in the US.
"It breaks through the limitation of catalytic efficiency of peroxidase mimics, which is a long-standing challenge in the field," Xia added.
In the study, the researchers found that when the nanoparticles were used in place of the conventional enzyme used in an ELISA -- peroxidase -- that the test was 300 times more sensitive at detecting carcinoembryonic antigen, a biomarker sometimes used to detect colorectal cancers.
And while a biomarker for colorectal cancer was used in the study, the technique could be used to detect biomarkers for other types of cancers and diseases, the researchers said.
The increase in sensitivity comes from nickel-platinum nanoparticle "mimics" that greatly increase the reaction efficiency of the test, which increases its colour output, and thus its detection ability.
Peroxidases found in the horseradish root have been widely used to generate colour in diagnostic tests for decades. However, they have limited reaction efficiency and thus colour output, which has inhibited the development of sensitive diagnostic tests, the team noted.
