Gold Nanoparticle SERS Textile Sensor
topic
Gold nanoparticles (AuNPs, 20–60 nm, synthesized by citrate reduction of HAuCl₄) immobilized on cotton or polyester via thiol-functionalization (3-mercaptopropyltrimethoxysilane, MPTMS) or polyelectrolyte layer-by-layer assembly at 0.05–0.5 g/m² Au loading create SERS-active substrates with electromagnetic enhancement factors of 10⁶–10⁹ at hot-spot junctions. AuNP-fabric SERS sensors detect pesticide residues (thiram, thiabendazole) at 1–10 ppb and explosive compounds (TNT, RDX) at 0.1–1 ppb by Raman spectroscopy (785 nm laser, 10–100 mW). Integration with portable Raman spectrometers enables field-deployable food safety and security textile sensors. Au nanoparticle plasmonic absorption peak at 520–560 nm (tunable by size) enables naked-eye colorimetric heavy metal (Pb²⁺, Hg²⁺) detection at 10–100 ppb by LSPR peak shift. Sensitivity maintained through 10 cycles of use and regeneration with 0.1 M NaOH wash.
Role
Enables wearable and portable chemical detection platforms by converting textile substrates into ultra-sensitive SERS sensors, providing field-deployable food contamination screening, explosive detection, and heavy metal monitoring in security and environmental applications.