Highly sensitive and specific resonance Rayleigh scattering detection of esophageal cancer cells via dual-aptamer target binding strategy

The modification of EGFR aptamer (Apt 1) and HER2 aptamer (Apt 2) with gold nanoparticles (AuNPs) is reported to obtain probe I (Apt 1-AuNPs) and probe II (Apt 2-AuNPs). Taking Eca109, KYSE510, and KYSE150 cells as models, the sandwich scattering system of probe I-cell-probe II was formed by the recognition of tumor markers by the aptamer modified probe, and the resonance Rayleigh scattering (RRS) spectra were investigated. The results showed that the scattering system can be used to quantitatively detect the Eca109 cell lines in the range 5.0×10 to 5.0×10 5 cells·mL −1 with a detection limit of 15 cells· mL −1 .The system can also detect the KYSE510 cell lines in a linear range of 5.0×10 to 5.0×10 5 cells·mL −1 with a detection limit of 18 cells·mL −1 and the KYSE150 cell lines in a linear range of 3.0×10 to 5.0×10 5 cells·mL −1 with a detection limit of 12 cells·mL −1 . To demonstrate the potential application of the RRS method for real sample analysis, cells were spiked into blank serum samples at concentrations from 1.0×10 2 to 1.0×10 5 cells·mL −1 . The recovery was between 97.0% and 102.3%, and the RSD was between 1.1% and 4.9%, confirming the feasibility of the proposed method for ESCC cell determination. Graphical abstract