Self-ordered silver nanoparticles on nanoconcave plasmonic lattices for SERS multi-antibiotic detection

Antibiotic detection at trace levels in different matrices is an important tool for environmental monitoring, clinical diagnostics, and pharmaceutical quality control. Using aluminum concavities covered with silver nanoparticles (AgNPs), this study introduces another approach for the surface-enhanced Raman spectroscopy (SERS) detection of antibiotics. The optimal substrate provided by the aluminum concavities and the outstanding plasmonic enhancement of the AgNPs greatly enhances the adsorbed Raman signals of the antibiotic molecules. First, we used a controlled magnetron sputtering technique to deposit AgNPs onto the SERS substrates, synthesized by anodizing aluminum into highly organized concave dimensions. Detection limits approaching the 10^-10 M concentration level, owing to an EF of 10⁸, proved that these substrates successfully detected various antibiotics, including amoxicillin and tetracycline. An in-depth examination of the SERS spectra revealed distinctive peaks that correspond to functional groups, allowing for the exact identification and quantification of the antibiotic compounds. The synergistic impact of the aluminum concavities and silver nanofractals results in extremely homogenous substrates that are reproducible and sensitive.