A novel triangular nanocolumn array substrate integrated microfluidic chip for prostate cancer CTCs capture and SERS detection

• The triangular column array with filamentous nanowires acted as SERS substrate. • A novel integrated-microfluidic chip applied for capture and detection of PC3 cell. • The hot spots generated by nanowires and nanogaps enhanced the SERS signals. • The filamentous nanowires aid in the extension and elongation of cell filopodia . We developed a new PMMA-triangular column nanoarray (PMMA-TCNA) substrate-integrated microfluidic chip for the capture and simultaneous surface-enhanced Raman scattering (SERS) of the PC3 cells. Conventional microfluidic chips are unable to facilitate in-situ SERS detection of captured tumor cells due to design defects. To address this issue, the functionalized SERS substrate was embedded in the microfluidic chip, which was prepared using soft lithography and e-beam deposition techniques with gold films. The prepared SERS substrate not only offered favorable micro-nano environment for the attachment of tumor cells, but also provided more specific surface sites for the modification of aptamers due to the nanostructure, which contributed to combine with the “sandwich” immunocomplexes of MGITC labeling-prion protein antibody/aptamer-conjugated SERS nanoprobes. The capture efficiencies of the PMMA-TCNA substrate integrated microfluidic chip was calculated as 86.87%, and in-situ detection of the captured tumor cells could be realized by labeling SERS nanoprobes. Therefore, we proposed PMMA-TCNA substrate-integrated microfluidic chip demonstrated significant potential for capturing and attaching PC3 cells, which could be used for the early diagnosis of prostate cancer and had certain potential clinical application value.