Multiplexed 2-D Diffusion Point-of-Care Test for Serum Markers of Cancer
The objective of this project is to develop a multianalyte point-of-care assay for serum markers of cancer. This assay consists of a nanoscale "nonfouling" poly(oligoethylene glycol methacrylate) brush coated glass chip that contains two types of printed microspots: "stable" microspots of capture antibodies and "soluble" microspots of detection reagents. A finger stick of blood is applied to the chip, and the protein analytes in the blood diffuse across the non-fouling brush and bind to the stable spots of capture antibodies embedded within the brush. Simultaneously, the blood dissolves the soluble spots of fluorescently labeled detection antibodies, which diffuse and bind to their respective analyte-bound capture antibody spots and generate a quantifiable signal. Detection is via a custom fluorescence detector that attaches to an Android smart phone and uses its camera to record an image of fluorescent spots that are converted to analyte concentration by a built in phone app.
We have chosen to target two widely accepted serum markers for cancer diagnosis: 1) PSA for prostate cancer, and 2) Alpha-fetoprotein for liver cancer, which are the 5th and 6th most common cancers worldwide. However, this assay can be utilized to target any analyte for which antibody pairs are available, and is hence broadly applicable to all immunoassays used for cancer diagnosis/prognosis. After validation of the POCT at Duke using analyte spiked chicken blood, we will the carry out a field test in the Zhejiang Provincial People's hospital using patient derived finger-stick blood samples.