Preparation of a shared chip for cell capturing and imaging with nanoparticle scaffold, nanogap and circulating tumor cell detection supplementary information

Aim: To achieve accurate detection of circulating tumor cells (CTCs) in a large-volume sample. Materials & methods: Silica nanoparticles were crosslinked layer-by-layer on glass slides as the substrate of a chip using polyacrylic acid. Polyacrylic acid was immobilized as a spacer and capture ligands were immobilized on the spacer. Results: The chip can be integrally applied to capture, post-treatment and imaging detection for CTCs. The detected cell numbers were 33 and 40 for 9 cell/ml samples and clinical blood samples (7.5 ml), respectively. The detection ratio of positive samples was 100%. Conclusion: The significantly increased detected number for CTCs indicates that this methodology may avoid or greatly reduce the false-negative ratio of positive clinical samples.