Label-free detection of tumor markers using field effect transistor (FET)-based biosensors for lung cancer diagnosis

Detection of tumor markers is important for cancer diagnosis. Field effect transistor (FET) has been recognized as a powerful technique for label-free, sensitive, real-time, and multifunctional biosensing. Here, we developed FET biosensors that allow the label-free detection of cytokeratin fragment 21-1 (CYFRA 21-1) and neuron-specific enolase (NSE), useful tumor markers for lung cancer type differentiation. It was found that the FET biosensor was capable of quantitatively detecting these tumor markers in both phosphate-buffered saline and human serum. Additionally, we developed a multianalyte FET biosensor for the selective multiplexed detection of CYFRA 21-1 and NSE at the same time, by integrating two antibody types on the same chip, providing a step towards the realization of sensor arrays. The multianalyte FET biosensor, as described herein, will help for lung cancer differential diagnosis with advantages of simple and rapid detection procedures, low sample consumption, and low cost.