Love wave based portable sensing system for on-line detection of carcinoembryonic antigen in exhaled breath condensate

Lung cancer is continuously the leading cause of cancer related death. Noninvasive exhaled breath condensate (EBC) detection using portable devices may pave a new avenue for monitoring conditions of the high-risk population of lung cancer, thereby increasing the 5-year survival rate. Here, a portable system is proposed for on-line detection of carcinoembryonic antigen (CEA) in EBC. This miniaturized system employs an aptameric Love-wave sensor to provide a detection with advantages of low cost, operational simplicity and high sensitivity. In addition, the aptasensor can be used in label-free and real-time monitoring. Integrating with measurement circuits and iOS APP, the system realizes online transmission and processing of signals which reflect the CEA concentration. Artificial samples have been detected, and experimental results demonstrate that the present system is sensitive (limit of detection = 1 ng/ml) and accurate (relative accuracy = 0.995). Applying in detection of clinical EBC, the relative error is as low as 0.305% and the result can be used to distinguish lung cancer patients from healthy subjects. Therefore, this portable system offers a potential solution for noninvasive detection of lung cancer in its early stage.