Paper-based plasmonic platform for sensitive, noninvasive, and rapid cancer screening

Surface-enhanced Raman scattering (SERS) fingerprints of individual molecules offer the possibility of multiplexing as well as cancer screening. A highly sensitive, noninvasive, and rapid cancer screening platform encompassing exfoliative cytology and paper-based SERS technology is described. The SERS substrate which consists of plasmonic gold nanorods (GNRs) adsorbed on a piece of filter paper forms the flexible and three-dimensional heterogeneous scaffold for cancer screening. Different and reproducible SERS spectra are obtained from normal and cancerous cells due to specific biomolecular changes in cancerous cells. A diagnostic algorithm based on the ratio of the spectra values is adopted to distinguish between cells exfoliated from 20 normal and cancerous tissues, and a high sensitivity of 100% and specificity of 100% are achieved by I1600/1440 (peak ratio of signals at 1600-1440 cm−1) and I1440/1340 (1440-1340 cm−1), which is better than I1600/1340 (1600-1340 cm−1) with a sensitivity of 70% and specificity of 60%. The combination of exfoliative cytology and paper-based plasmonic technology enables highly sensitive, rapid, and non-invasive cancer screening and has large clinical potential.