Multifunctional Ag-Decorated MoS2 Nanosheets for Highly Sensitive SERS-Based Monitoring of Ibrutinib

Semiconductor–noble metal hybrids have emerged as attractive surface-enhanced Raman scattering (SERS) platforms for pharmaceutical analysis because they integrate interfacial chemical interactions with plasmon-mediated electromagnetic enhancement. Herein, a semiconductor–noble metal hybrid SERS substrate was constructed by sputtering Ag nanoparticles (NPs) onto exfoliated MoS2 nanosheets (NSs) and was applied to the quantitative detection of ibrutinib. Within this hybrid architecture, accessible surfaces for analyte adsorption were provided by the exfoliated MoS2 NSs, while plasmonically coupled electromagnetic “hotspots” were generated by the Ag NPs, as further supported by finite-difference time-domain (FDTD) simulations. The optimized substrate enabled quantitative SERS detection of ibrutinib over 10−6–10−2 mg mL−1 (R2 = 0.991), with a detection limit of 3.73 × 10−8 mg mL−1 and a relative standard deviation of 5.81%. These results demonstrate the potential of Ag-decorated MoS2 NSs for sensitive SERS detection of ibrutinib in standard solutions.