Electrical Profiling and Aptamer Functionalized Nanotextured Surface in a Single Biochip for the Detection of Tumor Cells

Early detection and accurate enumeration of rare tumor cells in the peripheral blood of cancer patients has enormous diagnostic potential. Highly sensitive approaches are needed for screening and timely diagnosis due to the scarcity of circulating tumor cells (CTCs) at early stages of cancer. Microfluidic devices have emerged as important platforms to detect and quantify tumor cells. This article reports a nanotextured microfluidic device to capture tumor cells with surface grafted anti-EGFR RNA aptamers coupled with translocation behavior based enumeration. Nanotextured polydimethylsiloxane (PDMS) surface was functionalized with aptamers to capture human glioblastoma (hGBM) cells while microchannels on either side of the capture region discriminated tumor cells based on their translocation behavior at single cell level. The translocation profile depended on mechanophysical properties of the cells. First of all, cell capture efficiency and translocation behavior of tumor and blood cells were determined. Eventually, tumor cells were mixed in blood at a concentration of 100 cells/ml and detected using the microfluidic device. The efficiency of the device was above 83% to detect metastatic hGBM cells from blood. The device facilitated multistage detection of tumor cells based on both their mechanophysical and biochemical properties. This lab-on-a-chip approach can be used for cancer screenings at point-of-care. aNano-Bio Lab, University of Texas at Arlington, Arlington, TX 76019, USA. *E-mail address of corresponding author: smiqbal@uta.edu bDepartment of Electrical Engineering, University of Texas at Arlington, Arlington, TX 76011, USA cNanotechnology Research Center, University of Texas at Arlington, Arlington, TX 76019, USA dDepartment of Interdisciplinary Studies and Department of Biology, University of Texas at Arlington, Arlington, TX 76011, USA eInstitute for Cell and Molecular Biology, University of Texas at Austin, Austin, TX 78712, USA fDepartment of Bioengineering, University of Texas at Arlington, Arlington, TX 76010, USA gDepartment of Urology, University of Texas Southwestern Medical Center at Dallas, Dallas, TX 75235, USA. # Equal Contribution