LbL-Antibody Embedded Gold Mesh: An Effective Method for Early Detection of Circulating Tumor Cells

The importance of early cancer diagnosis has been recognized for decades, driving the demand for technological advancements and novel strategies for cancer detection. The conventional detection of circulating tumor cells (CTCs) often relies on size-based separation to distinguish CTCs from other blood cells. However, this method frequently leads to significant cell congestion and poorly recognizable fluorescent images, which inevitably reduces the sensitivity and specificity of CTC detection. Most CTC current separation devices with a cell filtration process have a cell capture efficiency ranging from 50% to 80% in clinical application.

We constructed a flexible antibody network on the surface of gold-plated iron meshes with a pore size of 20 μm using the layer-by-layer (LbL) assembly technique. These meshes were then used to enrich MCF7 cells and CTCs in 10 clinical blood samples from breast cancer patients.

This antibody network reduced the effective pore size, thereby improving both capture efficiency and specificity for CTCs. In a cell line separation study, meshes with a trilayered antibody network demonstrated a capture efficiency of 65% compared to 26% for those with a single layer. In tests using clinical samples, the trilayered antibody network achieved 100% accuracy, whereas the single-layer configuration only reached 40%. The multilayered antibody network shows strong potential for enhancing widely used immunosensors.