Screening of Near-IR Surface-Enhanced Raman Scattering (SERS) Dyes Using Quick Freezing-Induced AuNP Aggregates (QFIAAs).

Near-IR (NIR) surface-enhanced Raman scattering (SERS) is an emerging bioimaging technique that can be a safe alternative with a resolution better than current bioimaging techniques, such as MRI, CT, and PET. These can be hazardous with long-term exposure due to powerful magnetic fields or ionizing radiation. The success of NIR SERS bioimaging partially lies in the selection of highly sensitive NIR Raman reporters, which is essential to achieve highly resolved bioimaging from the body system. NIR Raman dyes must satisfy three important conditions: strong absorption in the NIR region, strong binding to the surfaces of gold nanoparticles (AuNPs), and excellent NIR SERS activity. AuNPs have been used as vital SERS substrates, but must be aggregated to create hot-spots to produce strong SERS signals. My research has focused on the applications of QFIAAs in the screening of dye molecules with high throughput for NIR SERS bioimaging. In this talk, the effect of the capping agents on the formation of QFIAAs, the charge effect of dye molecules on their adsorption on QFIAAs, and the results of a proof-of-concept experiment on using QFIAAs to screen dye molecules for NIR SERS will be presented