The goal of this project is to develop a portable, user-friendly diagnostic device that can be operated without specialized personnel or laboratory infrastructure. By combining disposable electrochemical chips with rationally designed synthetic DNA architectures, the device enables the rapid and simultaneous detection and quantification of antibodies against CA125, CA19-9 and PSA, clinically relevant biomarkers that play key roles in diagnosing of ovarian, pancreatic and prostate cancer, respectively.