Research Projects

Surface-enhanced Raman scattering (SERS) has emerged as a transformative analytical technique, offering unparalleled sensitivity and molecular specificity for detecting trace analytes, including health biomarkers. However, its widespread adoption is hindered by the lack of reproducible, high-performance substrates capable of consistent signal amplification. SERS substrates rely heavily on localized "hotspots" for signal enhancement, but low analyte concentrations often prevent molecules from reaching these active zones, hindering quantification. Achieving uniform, high-yield hotspots with chemical stability remains challenging. While drop-casting is a common deposition method, the "coffee ring effect" causes uneven solute accumulation at droplet edges, leading to inconsistent SERS signals. Laser-based surface modification overcomes these limitations by enabling precise, maskless nanopatterning with extreme wettability control. Techniques like ultrafast laser direct writing, LIPSS (laser-induced periodic surface structures) and laser assisted functionalization allow high-throughput fabrication of uniform nanostructures, enhancing SERS reproducibility and expanding applications in sensing and wettability engineering. This project addresses this critical issue by leveraging ultrafast laser-driven nanopatterning to fabricate uniform, high-enhancement-factor SERS substrates with precisely engineered plasmonic hotspots. By optimizing laser parameters—such as wavelength, fluence, and polarization—we aim to create nanostructured surfaces that combine electromagnetic enhancement with super hydrophobicity, enabling precise analyte concentration at the detection sites. The proposed substrates will overcome the limitations of traditional nanoparticle-based systems, which suffer from aggregation and poor batch-to-batch reproducibility, by achieving low signal variation and detection limits better than 10⁻¹² M. While global research has demonstrated remarkable progress in laser-fabricated SERS substrates, India faces unique challenges in standardization and cost-effective implementation. Current clinical vitamin testing methods (e.g. Vitamins B12 and D3) remain prohibitively expensive (₹1000–2000 per test), creating barriers to widespread health monitoring. Our project addresses these limitations by developing innovative laser-nanostructured SERS platforms that dramatically reduce testing costs while maintaining high sensitivity. By moving beyond conventional noble-metal systems and optimizing fabrication protocols for scalability, we aim to create sustainable detection platforms with superior performance compared to existing hybrid nanomaterials. This technology has the potential to transform nutritional monitoring in resource-limited settings, offering rapid, affordable, and reliable testing alternatives.