Arrayed microfluidic chip for detection of circulating tumor cells and evaluation of drug potency

Circulating tumor cells (CTCs) from peripheral blood of cancer patients are considered as one of the most promising pharmacodynamic (PD) biomarkers due to its non-invasive property in disease diagnosis and prognosis. However, the detection of extremely low number of CTCs in patient blood requires methods with high sensitivity and accuracy. We fabricated an arrayed geometrically enhanced mixing (GEM) chip with a "dislocation herringbone" layout based on cell immunoaffinity. By optimizing the injection and rinsing flow rate, an average cell capture rate of 87.02% and an average capture purity of 99.58% were achieved using the human lung adenocarcinoma cell lines H1975. In addition, we determined the specificity, precision, accuracy, and detection limit of our chip. The results demonstrated the chip was stable, accurate and reliable for the "liquid biopsy" of lung cancer cells using the peripheral blood of patients. Our chip can also be used to evaluate the potency of different drugs against tumor cells in parallel due to the presence of four independent microchannels.