Toward Dynamic Detection of Circulating Tumor Cells Exploiting Specific Molecular Recognition Elements

Dynamic detection, as one of the core tenets in tumor diagnosis, relies on specific recognition, rapid reaction, and significant signal output. Circulating tumor cells that carry the most complete information of neoplastic lesions are analytes of interest for sensor designer. To overcome the deficiencies in the use of antibodies, some antibody-like structures were used to integrate chemosensors, such as molecularly imprinted polymers (MIPs) and aptamer conjugates that may perform specific detection of analytes. The sensors inherited from such structurally stable molecular recognition materials have the advantage of being cost-effective, rapid-to-fabricate and easy-to-use, whilst exhibiting specificity comparable to antibody-based kits. Moreover, the fabricated sensors may automatically perform quantitative analysis via digital and microfluidic devices, facilitating advances in wearable sensors, meanwhile bringing new opportunities and challenges. Although most MIPs-based sensors for tumor diagnosis to date have not been practically used in hospitals, with no doubt, material innovation and artificial intelligence development are the driving forces to push the process forward. At the same time, the challenges and opportunities of these sensors moving forward to intelligent and implantable devices are discussed.