Utilizing Electron-Sink-Enhanced Nanoshells for Amplified Nanoplasmonic SERS-Based In Situ Detection of Cancer Cells, Linking Signal Enhancement with Cellular Damage

Abstract

A novel method is presented for detecting cancer cells and assessing apoptosis using electron-sink-enhanced surface-enhanced Raman scattering (SERS) via active electron transfer. By coating gold (Au) shells with electroactive liposome membranes (ELMs) derived from Shewanella oneidensis MR-1, the SERS signal is enhanced through chemical mechanism (CM) enhancement driven by electron transfer. The ELMs first donate electrons to the Au shells, which, upon laser excitation, amplify the local electromagnetic field, resulting in stronger Raman signals from the attached probing molecules. Additionally, the electron flow from cancer cells into the Au shells correlates with apoptosis, producing a strong SERS signal, while normal cells exhibit weaker signals. This method enables real-time monitoring of cancer cell apoptosis, distinguishing cancer cells from normal cells based on the enhanced Raman signal linked to electron flow. This approach marks a breakthrough in CM-based SERS applications, offering a sensitive method for cancer detection through the measurement of electron flow.