Akademik Veri Yönetim Sistemi
PLASMONICS, 2025 (SCI-Expanded, Scopus)
Label-free surface plasmon resonance (SPR) biosensors are powerful analytical platforms for real-time monitoring of molecular interactions. However, their performance is often limited by insufficient surface area, weak molecular binding, and non-uniform film morphology. Here, we report a cryogenically engineered plasmonic substrate based on gold nanoparticles (AuNPs) coated with a UiO-66-PDC metal-organic framework (MOF) shell (Au@UiO-66-PDC; PDC: 2,5-pyridine dicarboxylate), designed to enhance refractive index sensitivity and spectral resolution. By lowering the spin-coating temperature to 230 K, we achieved more homogeneous MOF coverage, improved nanoparticle dispersion, and narrower inter-particle gaps compared to conventional room-temperature (300 K) deposition. FESEM analyses confirmed the formation of smoother, denser films at 230 K, while SPR measurements revealed a substantial improvement in sensing performance. The refractive index sensitivity increased from 179.6 degrees/RIU (300 K) to 202.6 degrees/RIU (230 K) at 9000 rpm, and the corresponding figure of merit (FOM = S/FWHM) improved from 123.9 to 176.2. Similar trends were observed across all spin coating speeds, demonstrating that both low temperature and high rotational speed synergistically enhance plasmonic coupling. Furthermore, the cryogenic Au@UiO-66-PDC substrate enabled high-affinity detection of mouse IgG1 kappa using immobilized Protein A/G, yielding kinetic parameters consistent with commercial reference values, confirming excellent biointerface quality. Overall, this study demonstrates that combining cryogenic spin-coating with MOF functionalization provides a powerful strategy to engineer high-performance SPR sensing platforms with enhanced sensitivity, spectral sharpness, and biochemical compatibility, paving the way for next-generation plasmonic biosensors.