Rare Molecule Biomarker Detection Using Dielectrophoresis Spectroscopy
Gudagunti, Fleming Dackson
More InformationShow full item record
According to the American cancer society, 1.9 million new cancer cases and 608,570 cancer deaths are projected to occur in the United States. There is a fundamental technology gap that prevents the availability of tools for the diagnosis of cancer and genetic diseases as well as the genetic predisposition to developing certain diseases such as diabetes, and cardiovascular disease. The prognosis of several types of cancer can be done through blood tests to detect the concentration level of the respective biomarkers. However, detecting biomarkers is still difficult with existing methods such as ELISA, Surface Plasmon resonance, and PCR techniques. The existing techniques have drawbacks due to complicated and time-consuming protocols, thus requiring the presence of an expert to handle complex and expensive pieces of equipment. Therefore, there is a need to develop a cost-effective transduction mechanism for biomarker detectors that could be used for cancer screening at the point-of-care preferably using as a single finger-prick blood droplet from the patients that have the combination of high sensitivity, high specificity, and low complexity to detect cancer at an early stage. To address the limitations on the current techniques for biomarker detection, we developed a label-free automated real-time image processing technique based on dielectrophoresis (DEP) spectroscopy that is an effective transduction mechanism of a biosensor for the disease biomarker detection. A substantial change in the negative DEP force applied to functionalized polystyrene microspheres (PM) was observed to both the concentration level of the disease biomarker and the frequency of the electric field produced by interdigitated gold microelectrode. The velocity of repulsion of the PM attached to the disease biomarker from the electrode was determined using a side illumination and automated software using a real-time image processing technique that captures the Mie scattering from the PM. Since negative DEP spectroscopy is an effective transduction mechanism for the detection of the cutoff levels of disease biomarker, it has the potential to be used in the early-stage diagnosis and the prognosis of cancer.