Ovarian cancer (OC), the most lethal gynecological cancer, is often referred to as the “silent” killer since early-stage symptoms are not radically different from normal conditions. Worldwide there are 150,000 deaths, annually; notably, the survival rate when OC is detected in stage I is over 90%. However, the only current diagnostic test for OC is notorious for providing both false positive and negative results. The common imaging modalities can not be used in the early stage and large scale for the disease. Accordingly, there is an urgent need for a low-cost screening test that is rapid, sensitive and selective, and can be applied to the general population. We have developed a simple, precise, and low-cost screening test using electrochemical techniques to fabricate a point-of-care testing (POCT) device for early detection of OC. The device detects Lysophosphatidic acid (LPA), a highly promising biomarker, which was found to be elevated in 90% of stage I OC patients and gradually increases as the disease progresses to later stages. Electrochemical techniques are highly sensitive and fast, and can be easily miniaturized, which will reduce the cost of the fabrication. The main challenge in developing such a tool is overcoming a ubiquitous, problematic phenomenon known as non-specific adsorption (NSA), which is due to the fouling of non-target molecules in the blood on the recognition surface of the device. To overcome the NSA, we have followed a unique and novel strategy using silane-based interfacial chemistry to modify medical-grade stainless steel electrodes. The biorecognition surface was developed using the affinity-based gelsolin-actin system, which was previously invented by our group to detect LPA using fluorescence spectroscopy.
This project provides a proof-of-concept for a diagnostic tool that could be conducted on a small sample of blood, in a similar manner to the blood glucose monitoring devices. The development of this POCT device would significantly improve the survival of ovarian cancer patients and would save millions of dollars for the healthcare system. Furthermore, this project will open new frontiers in POCT by advancing the current knowledge in anti-fouling strategies.