Label-free Detection of Breast Cancer Cells Using a Fiber-optic Grating Sensor Functionalized with Halloysite Nanotubes

A breast cancer cell detection method by using a tilted fiber Bragg gratings (TFBGs) coated with halloysite nanotubes (HNTs) has been proposed and a limit of detection of 10 cells/mL has been experimental achieved with good reproducibility. Experiments have shown that the capture of MCF-7 cells by peristaltic pump is much higher than that by static cell solution. Compared with normal cells, the HNTs coating is able to capture tumor cells better, because the surface morphology of the HNTs can make cancer cells adhere well. In the detection of tumor cells, the integration of TFBGs with microfluidic channels enables precise measurement control over samples with sub-microliter volumes and does not require accurate temperature control because of the elimination of the temperature cross-sensitivity inherent in TFBG devices. The proposed optical fiber/microfluidic biosensor represents an appealing solution for rapid, low consumption and highly sensitive detection of analytes at low concentrations in medicine monitoring.