Novel methods for improving the robustness of quantitative metal nanoparticle surface-enhanced Raman measurements

However, traditional IS methods, which rely on strongly scattering molecules, have drawbacks, including competition for surface space with target analytes and potential signal overlap, especially for complex analytes.<br><br>This thesis first investigates an alternative IS approach using chemically-matched fragments of target molecules, which improves response consistency and extends detection to concentrations beyond monolayer coverage.

This approach allows more accurate signal calibration for complex analytes. The second focus is the development of ultra-stable SERS-active colloidal aggregates using a low-viscosity, unreactive hydrogel to stabilize NP aggregates while minimizing interference with analyte diffusion. A model based on independent polymer coils preventing further aggregation of NP clusters was proposed.

This substrate consistently produces reliable, time-independent SERS results, overcoming typical stability issues. Additionally, derivatives of this substrate demonstrate enhanced performance beyond traditional colloidal aggregates. This innovative approach provides a foundation for further applications in SERS-based analysis.<br><br><i>Thesis is embargoed until 31st December 2029</i>.<br><br>