Real-time detection of mesothelin in pancreatic cancer cell line supernatant using an acoustic wave immunosensor

Background: An acoustic wave immunosensor was developed to illustrate the viability of such devices in early detection of molecular cancer biomarkers. The methods described here involve a real-time, less invasive technique for detecting mesothelin, a protein that has been linked to pancreatic and ovarian cancer. Methods: Antibodies were immobilized on the gold surface of the device via a self-assembled alkanethiol monolayer. Supernatant from two different pancreatic cancer cell-lines (PL1 and CAPAN2) containing an unknown concentration of mesothelin was tested for the protein by a flow-through analytical technique in three types of experiments. Binding of the mesothelin to the immobilized antibody layer caused a shift in the device's resonant frequency, which was correlated to the concentration of supernatant. A reference sensor was used to correct for frequency shifts caused by pressure or viscosity effects from the injection of the supernatant solution. Results: Repeated experiments indicate that the sensors are capable of nanogram detection thresholds of mesothelin proteins at room temperature and in complex mixture. Conclusions: Acoustic wave device biosensors have the potential to become a valuable tool in screening for pancreatic as well as other types of cancers. The main features include real-time detection, high sensitivity, and ease of use.