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

## TL;DR

This paper presents a new SERS method using silver nanoparticles on aluminum concavities to detect antibiotics at very low concentrations.

## Contribution

A novel SERS substrate combining nanoconcave plasmonic lattices and silver nanoparticles for multi-antibiotic detection is introduced.

## Key findings

- Detection limits as low as 10−10 M were achieved using substrates with an enhancement factor of 108.
- The method successfully detected antibiotics like amoxicillin and tetracycline through distinct Raman spectral peaks.
- The combination of aluminum concavities and silver nanofractals produced highly reproducible and sensitive substrates.

## Abstract

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.