Chemically renewable SERS sensor for the inspection of H2O2 residue in food stuff

Hydrogen peroxide (H 2 O 2 ) residue in foodstuffs will bring great harm to human health. We immobilize the composite of the reduced polyaniline (PANI R ) modified gold nanoparticles on the surface of ITO (ITO/AuNPs/PANI R ) to develop surface-enhanced Raman scattering (SERS) sensor for H 2 O 2. detection. The principle is that PANI R is oxidized by H 2 O 2 to generate a new SERS peak at 1460 cm −1 for realizing quantitative analysis of H 2 O 2 . Fe 2+ -Fenton reaction is introduced to catalytically react with H 2 O 2 to hydroxyl radical, which speeds up the oxidation of PANI R . Before SERS detection, acidic treatment could guarantee the reduced state of PANI R in composite. Limit of detection of ITO/AuNPs/PANI R -based SERS assay for H 2 O 2 is down to 1.78 × 10 −12 mol/L and a good linear relationship from 1 × 10 −10 to 3.16 × 10 −7 mol/L is achieved. Furthermore, the SERS sensor could be regenerated by acidic treatment. As a scenario, the renewable SERS sensor is utilized to monitor H 2 O 2 residues in food and environmental samples.